Reducing Stress Factors in User Interfaces

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Reducing Stress Factors in User Interfaces

Govert-Jan Slob

May 2012

Student number: 3219615

Mentor: dr. R.M. van Eijk


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Contents

Reducing Stress Factors in User Interfaces ................................................................................ 1

Contents ...................................................................................................................................... 2Introduction ................................................................................................................................ 4

1. Contemporary computer usage ............................................................................................... 5

2. Stress ...................................................................................................................................... 6

2.1 Stress on a physiological level .......................................................................................... 6

2.2 The relaxation response .................................................................................................... 7

2.3 Stressor characteristics ..................................................................................................... 7

2.4 Additional stressor characteristics .................................................................................... 9

2.5 The relativity of stressors ................................................................................................. 9

2.6 Towards stress-less software .......................................................................................... 10

3. Calming technologies ........................................................................................................... 10

3.1 Stress-less design heuristics ............................................................................................ 10

3.1.1 Not offering visible ability to control interruptions. .................................................... 11

3.1.2 Inducing the feeling of being overwhelmed. ............................................................... 12

3.1.3 Giving an uncertain image of time passing by. ........................................................... 12

3.1.4 Using inappropriate tone and emotion. ........................................................................ 13

3.1.5Not providing positive feedback to user input and events ........................................... 16

3.1.6 Encouraging prosocial interaction ............................................................................... 16

3.1.7 Inducing time-pressure ................................................................................................ 17

3.1.8 Using naturally calming elements ............................................................................... 17

3.1.9 Not acknowledging reasonable user actions ................................................................ 18

3.1.10 A mystified interface. ................................................................................................ 19

4. Designing a test environment ............................................................................................... 19

4.1 Measuring stress responses ............................................................................................. 20

4.2 Experiment Task ............................................................................................................. 20

4.3 Testing heuristic 1: Reveal ability to control interruptions ............................................ 22

4.4 Testing heuristic 2: Reduce feelings over being overwhelmed ...................................... 23

4.5 Testing heuristic 3: Acknowledge human interpretations of time passing by ................ 25

4.6 Testing heuristic 4: Use appropriate human tone and emotion ...................................... 26

4.7 Testing heuristic 5: Provide positive feedback to user input and events ........................ 28


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4.8 Testing heuristic 6: Encourage prosocial interaction ..................................................... 30

4.9 Testing heuristic 7: Relieve time-pressure ..................................................................... 31

4.10 Testing heuristic 8: Choose naturally calming elements .............................................. 32

4.11 Testing heuristic 9: Acknowledge reasonable user actions .......................................... 33

4.12 Testing heuristic 10: Demystify the interface ............................................................... 34

4.13 Towards a good set of heuristics .................................................................................. 35

5. Conclusion ............................................................................................................................ 36

References ................................................................................................................................ 38


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Introduction

Stress is an often used term in our society, and most people will admit to suffer from stress on

a regular basis. Job stress, emotions running high at home, and time pressure are some

instances of stress that come to mind. Apart from the occasional frustration caused by

malfunctioning hardware or software, stress is not often related to the use of computers.

However, stress invoked through the use of non user friendly software can certainly be

influential, because computers play an important part in our lives, and people use them for

extended periods of time on a daily basis.

People interact with computers through the user interface of the software. It could be

beneficial to know how stress can occur through interaction with user interfaces, which

principles are at the root of the cause, and how invoking stress can be avoided. By gaining

knowledge of these subjects, we can make steps towards developing software that is more

user friendly, because it invokes a minimal amount of stress. Would it not be most pleasant tobe able to send e-mails, use your word processor and browse the web while remaining in a

calm state of mind and body?

At Stanford Universitys Calming Technology Lab Neema Moraveji and Charlton Soesanto

have laid the basis for the interest in stress in relation to user interfaces. They have written the

CHI 12 paper Towards Stress-less User Interfaces: 10 Heuristics Based on the

Psychophysiology of Stress, in which they describe ten guidelines to develop software that

provokes a minimum of stress in users. This paper will form the basis of this thesis.

The goal of this thesis is to discover which factors in user interfaces can induce stress or calm,and to find out if we can adequately translate these findings into valid heuristics. To achieve

this goal, I have done an examination of the literature on stress and relaxation, human

computer interaction and calming technology.

After introducing the reader to the concept of stress, I will discuss which properties of user

interfaces can invoke stress in users, and why. Then I will review the heuristics that Moraveji

and Soesanto (2012) developed to guide the development of stress-less user interfaces.

Because these heuristics are brand new, I will finish with a description of a design for an

experiment to test the heuristics for effectiveness.


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1. Contemporary computer usage

Computers have become an important part of our everyday lives and so has the software

running on the computer devices. What used to be a desktop device dedicated to business and

office applications has turned into much more than that, and computers have become an

integral part of our lives. Most people spend hours browsing the web, playing games, listening

to music and engaging in social interaction through the use of computers every day. The term

computer does no longer solely refer to a desktop model: computers have also taken the

form of small mobile devices like netbooks and tablets, and even smartphones can be seen as

small computers.

The fact that computers have become so mobile and are being used in so many aspects of our

lives means that computers and software are becoming ubiquitous: they are everywhere. The

right term for this phenomenon is ubiquitous computing: the seamless integration of

computers into everyday objects and activities (Weiser, 1991). According to Weiser, we willin the future be surrounded by hundreds of computers in every room, which we will use

unconsciously to complete our tasks (Weiser, 1991). Although we do not yet live in a world

of ubiquitous computing, we are rapidly moving towards it. Because people now use

computers and software on such a frequent basis, and will be doing even more so in the near

future, computers have a large impact on our daily lives.

The increasing impact that computers have on our lives calls for increased attention to

usability of software and the effects that the use of software has on people. The better the

usability of the software applications is, the more control software developers have over

impacting the users of software in a desired way. If software is, for example, easy and maybeeven fun to use, users will be inclined to use the software more often. Computer scientists in

the fields of usability engineering and interaction design have devoted their time and effort to

developing methods for designing and evaluating software to obtain maximum usability.

Jacob Nielsen is probably the best known scientist involved in usability engineering. The

design heuristics he has developed are the leading source for software developers looking to

design user friendly software and have set the definition of usability. Nielsen's best known

heuristics are the 10 he published in 1994: Visibility of system status, Match between system

and the real world, User control and freedom, Consistency and standards, Error prevention,

Recognition rather than recall, Flexibility and efficiency of use, Aesthetic and minimalisticdesign, Help users recognize, diagnose, and recover from errors, and Help and documentation

(Nielsen, 2005).

Because of the available knowledge on usability and the user experience, most software

applications nowadays are expected to have a certain degree of usability. What contemporary

software design and evaluation guidelines do not incorporate are means to make sure a

software product does not induce feelings of stress.


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2. Stress

Stress, simply defined, is the nonspecific response of the body to any demand made upon it

(Selye, 1973, p. 692). In the case of stress, our bodies respond with biochemical changes to

cope with the extra demands of the situation. When talking about stress, it is important to

discern between the stressor and the stress response. The stressor, is the event or stimulus

causing stress in someone, an earthquake for example. The stress response is the bodys

response to the event (Selye, as cited by Lupien, Maheu, Tu, Fiocco & Schramek, 2007). In

this thesis I use stress and stress response to refer to the same phenomenon.The situation

that produces the stressor, is not necessarily unpleasant: an athlete running 400 meters also

experiences the bodys reaction to the demands placed upon his body by the situation (Selye,

1973).Stressors can be relative or absolute: an absolute stressor is a stressor that induces a

stress response in every person, such as being in an accident. Because of the aversive nature

of an absolute stressor, a stress response will be incited because ones survival and/or well-

being is at stake. A relative stressor is a stressor that induces a stress response in only part of

the population, such as a public speech. This is because relative stressors require a cognitive

interpretation, called appraisal, and the outcome of this interpretation decides the degree in

which a stress response will occur (Lupien, Maheu, Tu, Fiocco & Schramek, 2007). A relative

stressor therefore, is of a psychological nature.Large variations between individuals in the

stress response to psychological challenges have been frequently reported by researchers.

(Lupien et al., 2007) This means that people experience stimuli in a different manner, and a

stimulus that causes a stress response in one individual may not cause a stress response in the

next person. In our society, relative stressors are far more common than absolute stressors,

and the focus of this writing will therefore be on relative (psychological) stressors.

2.1 Stress on a physiological level

On a physiological level the stress response is often, but not always, characterized by the

secretion of stress hormones. When a situation is interpreted as being stressful, our

hypothalamus releases a hormone called corticotropin (CRH) which in turn triggers the

release of another hormone called adrenocorticotropin (ACTH) from the pituitary gland,

which is also a brain structure (Lupien et al., 2007). ACTH travels in the blood and reaches

the adrenal glands, located above our kidneys, which then secrete the so-called stress

hormones glucocorticoids (called cortisol) and cathecholamines (called adrenaline). The

glucocorticoids and cathecholamines make sure our bodies are able to meet the increased

metabolic demands. The secretion of these two stress hormones constitutes the start of the

stress response where one would, for instance, experience an increase in heart rate and blood

pressure to better cope with a situation (Lupien et al., 2007).

However, not all events that are perceived as stressful lead to the secretion of the stress

hormones glucocorticoids and cathecholamines (Anisman & Merali, 1999; Dickerson &

Kemeny, 2004). Stress hormone levels therefore cannot function well enough as an index of

the stress response. Furthermore glucocorticoids can also be released in response to positive,

non stress evoking stimuli. Another factor complicating stress measurement are the individual

differences in the perception and appraisal of a stimulus as being stressful (Anisman &


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Merali, 1999). These interpersonal differences make reliably measuring stress responses

difficult.

The stress response that our bodies give when faced with a stressor of some kind is a

necessity, and it is not necessarily bad. The altered physiological state of our body in the face

of stressors helps us survive and perform better. It is only when the stress response would

continue chronically or when it is elicited very frequently that our bodies are in danger of

being impacted by the negative aspects of the stress response (Stefano & Esch, 2006). One

can also experience positive stress: stress related to positive experiences like getting a

promotion, watching a scary movie or engaging in a challenge. Hans Selye (as cited in Lupien

2007) used the terms distress and eustress to differentiate between harmless positive stress

and possibly harmful negative stress responses. In this writing I focus on distress in relation to

user interfaces. There are many domains on which stress can have a negative impact. Stress

has, been empirically connected with cognitive performance and memory (de Quervain, D. J.,

Henke, K., Aerni, A., Treyer, V., McGaugh, J. L., Bertold, T., et al., 2003; Kopell, Wittner,Lunde, Warrick & Edwards, 1970), depression, neurotic impairment, and other psychological

symptomatology (Smyth, Ockenfels, Porter, Kirschbaum, Hellhammer & Stone, 1998)as well

as increased susceptibility to infectious disease (Lupien et al, 2007).

2.2 The relaxation response

In a stressful situation our bodys stress response helps us to better handle the demands

posited by the situation. When the situation no longer demands extra performance, our body

does not need to allocate extra resources to certain areas anymore, and we can enter a state of

relaxation. The state of relaxation is reached via the relaxation response: a physiological

response characterized by decreased arousal, diminished heart rate, respiratory rate and blood

pressure (Benson, 1983). The relaxation responses terminates other physiological processes

normally associated with stress (Stefano, Fricchione & Esch, 2006). Once stimulated, the

relaxation response induces positive effects for the person invoking the process (Stefano et al.,

2006)and this calm state can even help the recovery from many illnesses (Benson, 1983).

Factors that evoke the relaxation response are called calmors. Like stressors calmors can be

relative or absolute, and the relaxation response depends on the interpretation of the

individual receiving the calmor (Moraveji et al., 2011b).

2.3 Stressor characteristicsAs I stated earlier, a stressor is often relative, meaning that the stress response is dependent on

the interpretation of the stressor, or absolute, meaning that the presence of a stress response is

a given fact. But what decides the outcome of the interpretation of the stressor? When will a

stimulus or event be interpreted as stressful or not?

To answer this question, we turn to the vast literature on stress and the influence of stressors

on the hypothalamic-pituitary-adrenal (HPA) axis. John Mason was a physician who spent

many years measuring the effects of various conditions - that he thought were stressful - on

the levels of stress hormones in human subjects. Mason's studies resulted in three main

psychological determinant factors that would cause a stress response in any individual


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exposed to them (Lupien et al., 2007). He concluded that when a situation feels novel and/or

unpredictable and/or gives the feeling that he or she does not have control over the situation,

a stress response can occur.

Dickerson and Kemeny (2004) measured cortisol responses and found support for the fact that

tasks in which an individual experiences outcome uncontrollability correlated with higher

cortisol values. However, the experience of loss of control had to occur in the context of

motivated performance tasks, in which a certain (important) goal was threatened, to elicit

cortisol changes. Uncontrollable contexts can include impossible tasks, time constraints, false

feedback of poor performance, and harassment (Dickerson & Kemeny, 2004). The authors

argue that uncontrollability may be intertwined with novelty, because situations are often

uncontrollable because they are new to a person.They also added that tasks in which

performance could be negatively judged by others, thus creating a social-evaluative threat,

provoke more cortisol changes than stressors without these particular threats. Videotaping as a

form of social evaluation also elevated cortisol responses, but real time presence of evaluativeothers caused greater cortisol elevations.However, in self-reports of distress, participants in

the experiments did not associate social-evaluative threat with greater increases of distress.

Dickerson and Kemeny (2004) showed that revealing negative aspects of the self in an

anonymous or confidential setting does not elevate cortisol levels" (p. 387).

According to Lazarus (1999) a situation will be appraised as being stressful when it is viewed

as a threatand has the potential to causeharm or loss (to a friendship, health or self-esteem).

Moraveji and Soesanto (2012) have added ones self or associated objects, living things, or

property (p. 2) to the list of possible things that are subject to harm or loss.

From the literature mentioned above and other literature, Moraveji and Soesanto (2012)

abstracted the following four characteristics of stressors that can lead to a psychological stress

response in humans. According to them software can invoke stress if it:

Feels unpredictable, uncertain, or unfamiliar. Evokes the perception of losing control. Has potential to cause harm or loss to one's self or associated objects, living things, or

property.

Is perceived as judgment or social evaluative threat including threats to one's identityor self-esteem.

It is worth noting that the above stressor characteristics have been abstracted from research,

but have not all been empirically tested. For example, I could not find reports of experiments

that were dedicated to testing whether unpredictability indeed invokes stress responses.

Moreover, there is little known about the impact that specific psychological stressors have on

humans, because most research stems from experiments with animals. There is however

evidence to back the claims that perception of losing control and social evaluative threats

cause stress (Dickerson & Kemeny, 2004).


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2.4 Additional stressor characteristics

According to Lazarus, emotions and stress go hand in hand. When an individual appraises the

fate of his goals or values in a situation, emotions arise. (Lazarus, 1999). Each emotion that is

experienced has a meaning, and knowing that meaning gives you information about how that

individual has appraised a situation. For example, if someone is angry, you know he isdemeaned or slighted by the situation. If emotions can be linked to their cause, they might be

useful to measure effects of possible stressors in user interfaces. Frustration is a good example

of an emotion that can often be related to a stressful situation. When a person has become

frustrated, it is clear that a stress response has been provoked by a certain stimulus.

Another feature with which a possible stressor could be identified, but that was not included

by Moraveji and Soesanto, is violating or endangering important goals or expectations.

Lazarus (1999) argues that a persons relationship with the environment becomes stressful

when what happens defeats or endangers important goal commitments and situational

intentions, or violates highly valued expectations (p. 60). If a certain situation endangersimportant goals or violates highly valued expectations, it might be a stressor.

2.5 The relativity of stressors

It might seem that a stressor containing any of the above characteristics will always cause

stress in a person that is subject to the stressor. It is of course not that simple. As I already

explained, almost all stimuli are subject to the appraisal by the individual receiving the

stimuli, before that stressor induces are stress response.Lazarus (1999, p. 60) argues for a

relational meaning approach to deal with individual differences in appraisal. In this

approach, a persons resources that can be allocated to cope with the situation determine

whether the relation with the environment is stressful or not. But more important, individual

differences in the significance of a persons appraisal are included to deal with the

subjectivity of stress.

According to Anisman and Merali (1999) the stress response can be mitigated by certain

factors in the context of the stressor. Characteristics of stressors that influence the impact of

stress response should be taken into consideration when appraising a stressor for its possible

impact on the user of the interface. The characteristics of stressors that can influence the

stress-induced effects are: the degree to which stress can be mitigated or eliminated by an

appropriate response, the predictability of onset of the stressor, the duration or chronicity of

exposure, and the timing and frequency of exposure (Anisman & Merali, 1999).

It is very difficult and perhaps impossible to predict the impact of stressors using the stressor

characteristics, which may severely limit their value. As I have stated earlier, stressor impact

depends not only on the stressors characteristics, but also on how an individual appraises the

situation that constitutes the stressor, and how that person copes with it. Furthermore, the

stressor characteristics are quite generic, and may need to be made more specific in order to

better identify stressors. For example, a definition of uncontrollable or threat is not

provided, so these terms can be interpreted in many ways.


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2.6 Towards stress-less software

In the above chapter I have explained what stress is and how the body reacts to the demands

of stressors. I also listed some stressor characteristics which, according to Moraveji and

Soesanto (2012), can induce stress responses. However, these stressors are relative and are

subject to interpretation: not everyone experiences a situation as unpredictable. Furthermore,these characteristics are still very generic. When, exactly, can a situation be characterized as

a threat to self-esteem or as evoking the perception of losing control ? It seems important

that these terms are made more specific, preferably by user testing. I also mentioned some

extra characteristics with which stressors can be identified, namely the presence of emotion

and the violation or endangering of important goals or expectations. Knowing these topics is

good, but how can this knowledge of stress and relaxation be useful to developers of software

products? That is what the next chapter is about.

3. Calming technologies

There is growing attention for the subject of stress among computer scientists worldwide. At

Stanford University, members of the Calming Technology Lab (CTL) have coined the term

'Calming Technology' to define "systems that induce cognitive, physiological and/or affective

states of calm for their users" (Moraveji, Opezzo, Habif & Pea, 2011b p.1). In other words,

Calming Technologies are (information) systems that are aimed at providing the user with

triggers to self-initiate calmors. A calmor, Moraveji, Oshidary, Pea and Fogg (2011) state, is a

source causing calm, like astressor is a source causing stress.

The people at CLT distinguish two fundamental types of calming technology, namely calm-

dedicated systems and calm-augmented systems. Calm-dedicated systems are systems created

explicitly and solely for calming purposes (Moraveji et al., 2011b). An example of a calm-

dedicated system is an iPhone application that provides the user with meditation techniques.

Calm-augmented systems on the other hand, are meant for a primary function but include

calming elements (Moraveji et al., 2011b). An example of a calm-augmented system is a word

processor with a minimalistic user interface and relaxing background music. Calming

technology can reduce stress in 2 ways: they can reduce the presence of factors that are

interpreted as stressors, or they can enhance the relaxation response. Calm-augmented

software is best suited for the first, and calm-dedicated for the second way.This thesismainly

focuses on calm-augmented systems. I believe that these are the systems for which it is most

important that they are developed to induce the smallest amount of psychological stress

possible. These are the systems that we use the most frequently and that are of the most

importance to us.

3.1 Stress-less design heuristics

To develop stress-less user interfaces, designers need to know exactly how to make a user

interface that is built to minimize stress provocation. What factors introduce or help omit

stressors and how can user interface elements be implemented accordingly? Design guidelines


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can help to provide answers to these questions and form a standard for designing stress-less

user interfaces.

Heuristics to achieve usability of software products already exist, and there may appear to be

some overlap between these, and the new stress reduction heuristics. The stress reduction

heuristics therefore are a complementation to the existing usability guidelines, and were not

created to reinvent the wheel say Moraveji and Soesanto (2012). Usability guidelines were

created to ensure usability, but not to reduce stress, and although the guidelines may overlap,

good usability might not ensure a stress-less user experience. On the other hand, a user

interface that adheres to the usability guidelines will most likely be easy to learn and

remember, efficient and satisfactory and provoke a minimum of errors. An interface that is

easy to learn and remember and that provokes little error will probably reduce the presence of

stressors like unpredictability and uncontrollability. However, adhering to stress reduction

guidelines that are specifically created to reduce stress should ensure an even more stress-less

user experience.

The following 10 heuristics were created by Moraveji and Soesanto (2012). They were made

with the aim to reduce the likelihood of an interface containing a known stressor. Because the

focus of this writing is on identifying stressors and calmors in software, I reversed most of

the heuristics to point out elements that a user interface should nothave, in order to reduce the

likelihood of an interface containing a stressor. Heuristics 6 and 8 seemed better off not being

reversed, so they should be interpreted as elements that a user interface shouldhave to induce

calm. I have also expanded the heuristics to contain more theoretical background and I have

tried to offer an explanation as to why a certain reversed heuristic will likely cause stress.

Finally, I attempted to suggest how certain stressors can be avoided or mitigated.

3.1.1 Not offering visible ability to control interruptions.

The first factor in software that is capable of causing stress is interrupting tasks. Users can be

interrupted by pop-ups, dialog boxes, or by distractions that draw the attention of the user

away from their primary task. According to Moraveji and Soesanto (2012) it is important to

have an interface show choices or settings to block, control or temporarily disable

interruptions during tasks that require large amounts of attention.When a user is interrupted

he or she may experience a loss of control over focus and task performance, because one

cannot continue working for some time. Interruptions may also give a user thefeeling of

unpredictability, when interrupted with an unexpected message. To help users control

interruptions, user interface developers should provide easy to find and use options to let the

users specify if they want to be interrupted and if so, how and how often.

McFarlane (2002) found that interruptions of a primary computer task had profound negative

effects on task performance, which dropped by 36% in the interrupted state. The subject

matter of the interruption can alter the effects of the interruption on task performance. When

relevancy between the matter of interruption and the primary task is high, the negative effect

of the interruption is moderated (Cutrell, Czerwinski & Horvitz, 2000).

Iqbal and Horvitz (2007) found that users lose context with the interrupted task, and that they

take longer to resume the task when there is no visual indicator that helps users remind the


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suspended task. To battle the loss of context, the authors propose to save the context of the

primary task as a whole, so it can be quickly recovered which helps resuming the primary

task. This helps users retaining control over their tasks.

Sometimes unimportant messages that are shown to the user in the form of pop-ups or

balloons, are displayed in such a way that they seem important even though they are not. For

example, in Windows XP a balloon pops up telling the user there are unused desktop icons.

Besides interrupting the user, this might give the user thefeeling of uncertainty as to whether

the messages are important or not and if not executing the response that is asked for could

cause harm to the user's system. In Windows 7, User Account Control (UAC) dims the screen

and makes actions impossible until one has clicked yes or no. This interrupts tasks,

causing the user to lose his focus on the primary task. It also creates uncertainty as to whether

the product for which the UAC interrupts the task will cause harm to ones computer or not if

clicked yes or no. The availability to control these interruptions is hidden in another part of

Windows.

3.1.2 Inducing the feeling of being overwhelmed.

The second heuristic of Moraveji and Soesanto (2012, p. 2) begins with the assertion that

large datasets are very common in applications that have many users and social elements or

use datasets on the web. Examples are web pages showing search results, menus with a lot of

breadth and a minimum of depth and sites like Facebook where users often feel they are

incapable of keeping up with the myriad of status updates.

According to Moraveji and Soesanto (2012) such interfaces can shape the possibility of

introducing stressors by making the users feel that they cannot control the amount ofinformation or that they will never be finished using the application (p. 2). They also argue

that a persons self-identity can be compromised because a user may feel he or she is not

engaging enough with the application, is not keeping up with other users or has not added

sufficient input (p. 2).

User interfaces that contain many visual elements of the same or different types can also

induce feelings of being overwhelmed. Visual clutter makes it harder for a user to quickly

scan the field and find what he or she is looking for. A cluttered interface puts a bigger

information load on the user and might invoke theperception of losing control.

According to this heuristic, user interfaces should offer simple, conveniently laid out screens

and must offer the possibility of specifying what interface elements should be shown or

hidden from view. Certainly in the early stages of learning how to use new software,

overwhelming the users is a realistic danger, because the amount of new information is the

largest. One could tackle this risk, by implementing a training feature that blocks certain

features from being accessed through the user interface, thus eliminating possible sources of

overwhelm.

3.1.3 Giving an uncertain image of time passing by.

According to Moraveji and Soesanto (2012) the progress indicators seen in current softwareproducts do not match the way humans interpret time passing by. A progress bar displays the


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progress of a system task from the systems perspective. Humans have a different perspective

on progress because they do not perceive time purely linearly, but experience time as slower

the longer one waits (Harrison, Amento, Kuznetsova & Bell, 2007). Harrison et al. (2007)

found that users experience time as being longer when looking at a progress bar in which

progress was visually slowed down near the end of the process. They perceived time as going

faster when progress was visually accelerated near the end of the progress, even if the total

time was the same. Harrison et al. (2007) abstracted from this that users are less tolerant to

negative progress behavior near the end of the line. Moraveji and Soesanto (2012) thus argue

that progress bars that slow down near the end can induce stress by creating unpredictability

about when the task finishesora lack of control over when one can use the system (p. 2).

A linear function will give an accurate and effective display of progress for tasks with static

completion conditions. These tasks are often not affected by progress slow-downs, and other

negative progress behavior. For tasks with completion conditions that can change on the fly,

and have inaccurate time estimates, progress bars can be augmented to give a representationof progress that better deals with a user's perception of time. Software developers should

therefore not use linear progress bar functions for dynamic processes if they want their users

to feel more calm. Instead, progres bars that intelligently distribute progress should be used.

These can, for example, help to reduce stress by caching progress at the start of the task, so

progress does not have to be visually slowed down near the end of the task.

Hogan (1978) suggests that an inverted u-shape can be applied to the relation between

perception of time duration and stimulus complexity, meaning that time is experienced as

longer when stimulus complexity is very low or very high. In practice, stimuli that bore us or

are too complex for us, cause time to be perceived as longer. Stimuli of average complexityhelp time to be perceived as shorter. User interface designers may be able to use this principle

by presenting appropriate stimulus complexity when users are waiting for a system process to

finish.

3.1.4 Using inappropriate tone and emotion.

Moraveji and Soesanto (2012) claim that stress can be induced because users engage

computers with over learned social behaviors such as politeness and reciprocity (p. 2). Users

seem to apply social rules and expectations to computers. If systems do not regard these

communication expectations that users have, stressors might be introduced because users are

unpleasantly surprised by inappropriate tone and emotion. The authors put forward that

designers should introduce human tone and conversational emotion when appropriate (p. 2).

A computer is not a person that expresses emotions of its own and is not aware of a users

emotions. A computer does not refer to itself as I, and it has no human-like attributes. In

pre-experimental interviews, users have acknowledged that computers should not be

understood in human terms and should not be treated as a person. Despite the above, users

still mindlessly apply social rules and expectations to computers (Nass and Moon, 2000).

According to Nass and Moon (2000) individuals overuse human social categories, apply

gender stereotypes to computers and ethnically identify with computer agents. For example,

users find a male computer voice more friendly when used for evaluating a users


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performance. Users also prefer male voices to handle masculine topics, and a female voice to

handle feminine topics. Concerning ethnicity, users identify more with computer agents of the

same ethnicity as their own.

Moraveji and Soesanto (2012) argue that users engage computers with politeness, and that

this should be taken into account when developing software. Reeves and Nass (1996)

conducted experiments in which participants communicated with computers and where asked

to evaluate a computers performance afterwards. Their conclusions where that computers are

social actors, and get the same treatment as people: users were polite towards computers, and

reciprocally, also expected the computer to be polite to them. Whether a computer presented

itself using text or voice did not make a difference. Reeves and Nass (1996) also argue that

when a technology (or a person) violates a politeness rule, the violation is viewed as social

incompetence and it is offensive (p. 29), so it is of major importance that a user interface is

polite. The findings by Reeves and Nass (1996) that people treat media as they treat people,

were called the Media Equation theory. Other research by Nass and Moon (2000) alsoshowed that users expect and execute reciprocity: if a computer was helpful towards the users,

they showed more helpfulness towards the computers too.

Goldstein, Alsi and Werdenhoff (2002) criticized the findings of Reeves and Nass that

people are polite to computers. They conducted an experiment similar to that of Reeves and

Nass (1996), but could not reproduce the results that Reeves and Nass found in their

experiment. They also argued that the experiment by Reeves and Nass (1996) was not set up

thoroughly enough to warrant reliable results. Goldstein et al. (2002) concluded from their

experiment that people are not polite towards small handheld computers, and that the Media

Equation theory should perhaps only be applied to desktop computers. Shechtman andHorowitz (2003) also criticized the Media Equation, because they found significant

differences between the behavior of participants towards computers and their behavior

towards humans. Like Goldstein et al. (2002), Shechtman and Horowitz argued that the

phenomenon of politeness towards computers should be further investigated before it can be

applied to user interface design.

The politeness theory created by Brown and Levinson in 1987 can be used to investigate the

role of politeness in user interfaces. According to this theory, politeness is about attenuating

threats to anothers face: a self-image someone wants to project. Two types of faces exist:

the positive face concerns desires to be liked, admired, ratified and related to positively, while

the negative face is about peoples freedom to act and not be imposed upon. The threats are

carried by face threatening acts: communication acts that damage ones face. A threat to

ones negative face is when an interlocutors freedom of action is obstructed. A threat to the

positive face occurs when the speaker does not care about someones feelings and desires.

Examples of face threatening acts are: expressions of disapproval, contradictions,

disagreements, interruptions and more (Brown and Levinson, as cited by Wikipedia, 2012).

To attenuate these face threatening acts, people apply certain politeness strategies. User

interfaces can also apply these tactics, to relieve stress caused by face-threatening acts.

Techniques to be polite include: indirect wording, the use of euphemisms, minimizingimposition and interruptions, apologetic wording and compliments.


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Another way to ensure that interaction with the user interface conforms to the expectations of

the users, such as politeness, is applying Grices Maxims. These are four basic principles that

constitute the rules of polite interaction (Reeves & Nass, 1996, p. 29). The principle of

quality says that speakers should always tell the truth, and preferably in an accurate way. User

interfaces usually tell the truth, but are not always accurate. For example, a user interface that

lets users know they are at step 3 of the process may be true, but is not very accurate if step 4

is 10 times more work than step 1. Quantity is about not contributing too little or too much to

the conversation. User interfaces frequently violate this rule, for example by giving rather

short and abstract error messages. The third maxim is that ofrelevance. According to this

rule, what one says should clearly relate to the purpose of the conversation (Reeves & Nass,

1996, p. 30). An example is disabling features or choices in menus, depending on the context

of the situation. The last maxim is clarity, and holds that contributions to an interaction

should not be obscure (p. 30). In user interface design, avoiding ambiguity in messages is a

form of clarity. However, one must be careful when trading ambiguity for precision, because

precision in the form of technical language can be hard to understand. An important point of

Grices maxims is that when a speaker, or user interface in this case, violates any of the rules,

users think of it as a violation of social conduct and will ascribe this to failure of the user

interface (Reeves & Nass, 1996).

In an experiment aimed at discovering if a polite computer tutor helps to take student affective

goals into account, Wang, Johnson, Rizzo, Shaw and Mayer (2005) implemented the

politeness theory of Brown and Levinson. They discovered that a polite computer agent had a

positive effect on self-efficacy and performance, but surprisingly the direct tutor agent was

rated as friendlier than the polite agent. These results can be valuable when designing user

interfaces, certainly when designing for human-tutor interaction.

Attributing human tone and conversational emotion to computers, or anthropomorphism, as

Moraveji and Soesanto (2012) seem to prescribe, might not create a solely positive experience

for users. Shneidermann (as cited in Sharp, Rogers & Preece, 2007) argues that attributing

human qualities to computer systems can make people feel anxious and make users feel

inferior or stupid. This is particularly true for those that use first-person dialog and screen

characters. The most heard complaint against computers that pretend to have human qualities,

is that people find them very annoying. On the other hand, Reeves and Nass (1996) reported

that human-like systems that praised and flattered users had a positive effect on how users feltabout themselves. Nevertheless, numerous other studies (Sharp, Rogers & Preece, 2007) have

shown that making interfaces more human is counterproductive. This is largely because

users expect the systems to be more human-like than they really are, and become disappointed

when they find out the systems are not that intelligent and affectively capable.

Implementing human tone and conversational emotion in user interfaces could help reduce

users perceiving unpredictability and threats to their self-esteem. Making software polite and

reciprocal towards users and taking gender and ethnicity into consideration could very well

help users feel more at ease while using the software. However, developers also need to be

aware of the negative effects that human-like interface agents might have, and that beingoverly polite can make users feel annoyed.


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3.1.5Not providing positive feedback to user input and events

The fifth design heuristic of Moraveji and Soesanto (2012) put forward posits negative

feedback as a stressor, and positive feedback as a calmor. This heuristic states that negative

feedback that is given by the system when users have, for example, entered invalid input or

tried to activate an unavailable feature, can induce stress. The system's negative response canthreaten one's self-esteem or trigger the feeling that users cannot control exactly how to

provide the information that is required. With regard to the fourth heuristic, Moraveji and

Soesanto (2012) say that negative feedback can also "violate expected norms of

conversational interaction with social agents, further increasing stress by being unpredictable"

(p. 2).

The authors also argue that by acknowledging successes and simplifying tasks, interfaces can

build confidence and resilience to stress in their users. In other words, positive messages that

acknowledge successes can be used to induce a calming effect. Negative feedback should be

omitted or rephrased more positive. Finally they propose that by pointing out mistakes that arecommon, users can realize they are not the only one that makes mistakes, and thus feel less

threat to their self-esteem.

By providing positive feedback to user input and events, user interfaces may help reduce

stressors. Designers have to be wary though, that users are not treated in a way that might

seem childish or overly simplified, as they might feel they are not taken seriously by the

system. While acknowledging successes, it seems important that an interface's messages are

not interpreted as a means to condition the user towards a desired behavior, for this may make

users feel annoyed or not taken serious. A message like Well done, you are doing great! may

be interpreted as patronizing by the users on the long term, which may threaten self-esteem.

3.1.6 Encouraging prosocial interaction

A very common context in which stressors often appear, is the context of social interaction.

When an individual is afraid that his or her task performance can be negatively judgedby

others, a stress response may occur (Dickerson & Kemeny, 2004). These stressors are most

likely to occur in a group context, a situation where software usage plays a trivial role.

However, even when used in a non group context, software applications can have a large

impact on maintaining our social lives. E-mail, Facebook and Twitter are the most obvious

examples of influential services that are enabled through a user interface.

Instances where a user thinks he fails at presenting himself to others in a desired way, are

situations where stressors may occur. According to Moraveji and Soesanto (2012),

"applications with social components have greater potential for stress as users manage self-

preservation" (p. 3). They argue that software that facilitates an dencourages prosocial

interaction can make the chance of social stressors occurring smaller, by integrating simple

ways of communicating prosocial interaction. An example of a software feature that is useful

for this purpose is spelling control, which makes the users feel more secure about the way

they present themselves to the outside world, because spelling is checked by a computer.

Other examples are likes and +1s which make communicating with others simple andlowers the risk of making an unwanted impression.


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3.1.7 Inducing time-pressure

Time pressure sometimes occurs during software usage, after having downloaded updates for

example. Moraveji and Soesanto (2012) argue that time pressure during interaction with

software can invoke stress responses. The reasons, according to the authors, are that "users

may feel a lack of control when they are pressured for time or even be worried about howthey appear in a competitive sense if the time they took to complete a task feels too long".

Relieving users from time pressure, by leaving out countdown timers from user interfaces and

not forcing users to take action within a certain time frame seems the appropriate counter to

this stressor.

Putting time pressure on people is known to cause stress responses when people appraise it

difficult to maintain their task goals (Maule and Hockey, as cited in Maule, Hockey and

Bdzola, 2000). Maule and Hockey found that participants that had to make decisions were

more anxious and energetic when presented with a deadline. The increase in anxiety and

being more energetic is accounted for by the awareness of the need to work harder whencompletion time is restricted, the authors argue. Long periods of continuous time-pressure

however, may just lead to increased fatigue say Maule, Hockey and Bdzola (2000).

An example of time pressure can be found in Windows Vista. It is known to put time pressure

on users after having installed an update. In Vista, the user is sometimes confronted with a

small window in which a small progress bar shows the time until the system will reboot to

finish the installation of a certain update that was automatically downloaded. This might give

user the feeling they are not in control of the time at which they want to reboot their system,

because the window puts timepressure on the users. Nowadays, most user interfaces do not

impose time pressure on users anymore, possibly making this heuristic slightly superfluous.

3.1.8 Using naturally calming elements

The eighth design heuristic brought forward by Moraveji and Soesanto (2012) is the use of

naturally calming elements to reduce stress. Integrating natural elements into user interfaces

and interactions should improve calmness in users. According to Ulrich et al. (1991), who did

research on stress recovery during exposure to natural environments, exposure to natural

elements can provide a shift towards a more positively-toned emotional state, positive

changes in physiological activity levels, and that these changes are accompanied by sustained

attention/intake (p. 201). The researchers showed that short exposure to (artificial) elements

of natural environments has an important function in facilitating recovery from stressors as

daily hassles and annoyances. Additionally, individuals exposed to natural settings reported

improved feeling states and showed lower stress levels in physiological indicators.

Participants exposed to natural settings showed much greater restoration in positive affects,

anger/aggression and fear. On a physiological level, participants exposed to nature settings

showed greater restoration from the stress indicators: muscle tension, heart pulse transit time

and skin conductance.

Japanese researchers found that allowing patients comforting background music during

anaesthesia, increases the acceptability of the experience of anaesthesia. Patients presentedwith calming background music also showed significantly lower blood pressure and heart rate


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during the recovery phases from anaesthesia (Tsuchiya et al., 2003). Swedish researchers

showed that music may decrease postoperative pain, and that postoperative music therapy

may reduce anxiety, pain and morphine consumption (Nilsson, Unosson & Rawal, 2005, p.

96). It appeared that slow and flowing music with 60 to 80 beats per second had positive

outcomes on relaxation and pain relief. Literature has suggested that music for therapeutic use

should have the following characteristics:

be non-lyrical,

consist predominantly of low tones,

comprise mostly strings with minimal brass or percussion (Nilsson, as cited by Nilsson,

2008), and

have a maximum volume level at 60 dB (Staum and Brotons, as cited by Nilsson, 2008).

This research raises the question if natural elements and music may also have a positive

influence on the unconsciousness of humans in other settings, like software usage. Becausethe mentioned experiments were not conducted with the use of computers, it remains unclear

if natural elements and music that are incorporated in user interfaces will have the same

positive effects on stress reduction during software usage. However, the results of the research

mentioned above certainly suggest the possibility.

3.1.9 Not acknowledging reasonable user actions

According to Moraveji and Soesanto (2012) a stress response can be triggered when a user

expects to take an action that is not available through the user interface. If the unavailable

action does not become available on short term, the stress response can grow. On any screen

or dialog, there exist a number of reasonable actions that users may want to take. Even ifthose actions are disallowed by the system, they should be acknowledged or guided in some

way, the authors say. Not acknowledging these actions may lead to stress because users can

perceive these situations as unpredictable or uncertain and as a loss of control.

Some user actions might not seem necessary from a developers point of view, but from a

users perspective they might be needed to ensure stress-less interaction with the software.

For example, users may find it important to have an undo action available at all times, so

they can easily recover from mistakes. Developers, unlikely to make mistakes, might not see

the importance of this action in many occasions. Not acknowledging user actions may evoke

theperception of losing control because a user can feel limited in his actions when reasonable

user actions are not sufficiently acknowledged. It may also introduce uncertainty and/or

unpredictability in some cases.

However, it might not always be a good idea to offer all the actions that the users expect.

There is even a usability principle, called constraints, that tells designers to restrict

interaction that can take place at a given moment (Sharp, Rogers & Preece, 2007).

Consequently, a balance between constraints and availability of actions is important when

seeking to reduce stress with this heuristic.


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3.1.10 A mystified interface.

The final design heuristic of Moraveji and Soesanto (2012) states that a user interface should

be demystified, meaning that one should not be presented with an interface that offers tens

of options of which the intended use is not directly clear. In other words: a user interface

should be self explanatory. An example of a mystical user interface is one in which buttonsare not accompanied by a title that explains their function, or one that uses very generic

appearance for the buttons. Unknown tokens and symbols can also counteract the principle of

this heuristic. A mystified interface may cause stress because it introduces uncertainty and

unpredictability, caused by unknown interface elements. It might also affect a users self-

esteem when he or she is forced to consult the manual or ask for help, when confronted with a

mystical interface element.

This heuristic seems to interact with the second heuristic of Moraveji and Soesanto (2012)

reducing the feelings of being overwhelmed, because a mystical interface is probably more

likely to appear overwhelming as more cognitive processing is required before things becomeclear. On the other hand, a lack of important interface elements may cause a more

minimalistic interface, which can be less overwhelming. For example: a user interface that has

mystical interface elements such as buttons without a title or description, requires more

thinking from the user, but contains fewer stimuli to overwhelm someone. The effect of a

mystified interface on being overwhelming is not yet clear and may need to be tested.

4. Designing a test environment

Thus far I have listed and explained several design heuristics that can be used to produce

stress-less user interfaces. When a user interface is being developed according to these

guidelines, it should offer a user experience that is characterized by a minimum of stressors

capable of invoking stress responses. At least in theory it should. To be able to determine if

the design heuristics are valid, and really achieve what they propose, the heuristics need to be

put to the test.

In the following section I have prepared a plan for developing a test and research environment

(TRE) that is aimed at testing the heuristics for legibility. The test environment will be a

software program that is able to reproduce several different conditions, by activating ordeactivating the implementation of the heuristics. By doing this, researchers can assess the

differences in the stress responses elicited by the users while they use the software. The most

obvious use of the test and research program is testing the effects of a stressful condition, in

which a heuristic is not taken into account or is implemented in the opposite way (thus

containing more stressors), versus a presumed stress-less condition in which a heuristic is

correctly implemented. If a heuristic does not seem to have a significant effect on stress

responses, it will need to be reviewed and adjusted.


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4.1 Measuring stress responses

Depending on the method, researchers can measure the levels of stress in the individuals

during, or after letting participants interact with the softwares user interface. Some methods

of measuring stress are: measuring cortisol levels through blood or saliva, measuring peoples

emotions, appraisals and other symptoms through questionnaires, and even measuring bloodpressure, heart rate variability and vagal tone.

Many scientists in the heretofore mentioned literature have used cortisol as an index for the

stress response. For the purpose of discovering what factors can make the use of software

stressful, it seems necessary to drop cortisol response as a measurement tool of stress. As I

stated in chapter one, not all events that are perceived as stressful lead to the secretion of the

stress hormones, and these hormones can also be released in response to positive, non stress

evoking stimuli. Another complicating factor, is the relatively mild nature of the stressors

present in user interfaces. Things like overwhelming interfaces and inappropriate tone and

emotion are unlikely to produce significant changes in levels of stress hormones, because thestakes during computer usage are not very high. However I believe it can cause stress that is

not directly followed by a physiological response. Software usage, when causing stress, is a

relative stressor and the induced stress will be determined by the appraisal and coping style of

the user.

Because of the interpersonal differences in appraisal of stressors, the interpersonal differences

in coping abilities and the unreliability of cortisol as an index of stress levels, stress responses

can be difficult to measure. A very accurate measurement tool may therefore be necessary.

Perhaps, a combined approach of the mentioned methods can be an effective means to

measure levels of stress in people working with user interfaces. Experts on stress

measurement should be conducted to develop an accurate method.

4.2 Experiment Task

To be able to create an effective experiment using the TRE, it is necessary that the software is

dedicated to performing a specific task that would also be carried out in daily life. I have

chosen for the TRE to be a word processor. Word processing is a common task that many

perform frequently, making it an important environment where the effects of design heuristics

can have a real impact.

Naturally, the users need a purpose for using the TRE, a task to fulfill while they participate inthe experiment. Giving the user a task to perform will help create a setting in which resembles

the way users normally use software. It is important that the task facilitates testing all the

heuristics, and thus meets all the requirements listed on the coming pages, and some general

requirements mentioned below.

An example of what an experiment task could look like is a task that is made of several

different subtasks. The subtasks are all different, which helps to provide sufficient diversity in

interaction with the user interface. In the experiment task, the participant is presented with

several documents that contain small assignments that the user is asked to fulfill. After

completing each assignment, the user is asked to save the document using a given filename


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format and close it. During the execution of these subtasks, the user makes use of different

features of the TRE to complete the assignments. The assignments should be as follows. In

the first task the users must change the color of the text in the first document to a custom color

they have created using the built in color picker. In the second task, the users have to insert a

table that has 15 rows and 5 columns, and insert data into the fields. In the third task, users

must insert a diagram, and fill it with data from the table they created in the second document.

They have to re-open the document from the second task to complete this task. In the fourth

task the users use the menu to navigate to, and insert a photograph that is located on the hard

drive. Extra assignments can be added to the experiment if this is deemed necessary.

General requirements:

The TRE features a general settings menu in which all features mentioned on thefollowing pages can be set up.

o Tick boxes to enable or disable features.o Text boxes for entering parameters.

The TRE must contain the basic features of word processing software. The user interface of the TRE must be designed according to contemporary usability

guidelines, so the enabling or disabling of the stress reduction heuristics is the main

variable influencing tress responses.


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4.3 Testing heuristic 1: Reveal ability to control interruptions

In the case of heuristic 1, the goal is to test if having control over the frequency with which

certain interruptions are allowed to appear, helps the users remain less stressed. The following

features are required in the TRE to perform a successful test:

Functional requirements:

An interrupting (pop-up) window must be able to appear and interrupt the user. After the first appearance, the user must be able to set the frequency with which a

certain interruption is allowed to appear.

The user must be able to escape/postpone the interruption.Nonfunctional requirements:

The ability to control interruptions must be accomplishable in only a few simple steps. The interruption must be clearly visible and impossible to ignore on first appearance.

To test if revealing or hiding the ability to control interruptions has an effect on a users stress

experience, users will need to perform the experiment task using the TRE. While performing

that task, the TRE must interrupt the user in such a way that they will be forced to shift their

attention away from their primary task, towards the interrupting interface element. The

interrupting interface element should block the desired visual field and so disrupt the users

work flow. The interruption should be a prominent but small window or box that pops up in

front of the main window that the user was viewing. The window or box must contain some

message or visual or auditory representation. When the user is interrupted for the first time,

they must be given the option to indicate how often the interruption is allowed to be shown

again in the future. This option must be available to the user in a clearly visible and easy to

operate manner, and it should be placed in the same window that comes with the interruption.

The option to disable or enable interruption possibilities should be incorporated in the general

settings menu of the software.

With these features, researchers can compare

two conditions. One in which a user is

confronted with an interruption of which the

frequency with which it appears cannot be

controlled. And a condition in which an

interruption occurs along with the option to

indicate whether it should re-appear at all, and

if so, how often.

Figure 1: Limited possibility to control interruptions

To properly test this heuristic, it is important to test the effect of being able to control the

appearance of interruptions as opposed to testing the effect of the interruption itself, which is

not the goal of this heuristic and is something that has already been researched by others

(McFarlane et al., 2002; Iqbal & Horvitz., 2007) It seems rather complex to distinguishbetween testing the effect of interruptions and testing the effect of the ability to control


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interruptions, because the first is needed to accomplish the second. I therefore suggest that

both be tested in conjunction.

An example of a TRE test situation: After having worked for 5 minutes the users are

presented a small window that appears in the middle of the users view and interrupts their

workflow. In the small window is a drop down menu in which are several options that change

the frequency with which this interruption will appear: set frequency to 60 minutes, 120

minutes, daily and an option to postpone the current interruption. There also are 2 buttons:

ignore, which will change nothing in the frequency of appearance, and OK, which will

confirm the selected option.

4.4 Testing heuristic 2: Reduce feelings over being overwhelmed

To experience if reducing the amount of information and reducing the amount of features and

options in user interfaces really makes the user experience less stressful, a test is required.

Again, the users must engage in performing the experiment task using the TRE, and these

features are needed:


The researcher must be able to select which interface elements must appear or not. The TREs user interface must be able to show a large number of interface elements. The interface elements must surround the workspace.

Nonfunctional requirements:

The interface must look overwhelming when all elements are enabled. The interface must be able to offer simple conveniently laid out screens.

The TRE must be able to present the users with a user interface that is filled with data,

information, features, tools, bars, menus and buttons. Due to these elements, the user interface

will appear overwhelming. This will make the users feel they have insufficient control over

the amount of information on display and makes it harder for them to focus in their primary

task. The TRE must also offer the possibility to change the appearance of the user interface

by changing it into a tidy, simplistic user interface. To do this, researchers must have access to

a settings menu in which they can choose to enable or disable certain interface elements to

create a non-overwhelming interface. In the TRE, the interface elements must be visible on all

four sides of the workspace when enabled.

With the help of the features described above, researchers can create 2 conditions to which

participants can be exposed. The first condition involves presenting an overwhelming

interface, enabling many interface elements. The second condition is the opposite of the first,

and here all interface elements are tuned to create a non-overwhelming interface. One must be

cautious not to disable too many interface elements, because an interface that is non-

overwhelming but also non-realistic might then be created.

An example of a TRE test situation: The user is presented with an interface that containsmany buttons, bars, windows and information. The workspace is surrounded by those


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elements, and the visual field is filled with information, making the user feel overwhelmed

with stimuli.

Figure 2: A user interface containing many elements.

Figure 3: A user interface containing few interface elements.

Figure 4: A user interface containing almost no interface elements.


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Above, I have provided three screenshots to illustrate the possible gradations of designing an

interface to reduce feelings of being overwhelmed. The first two screenshots are from

Microsofts Word 2007, the first using the standard user interface, the second using a user

interface adapted to the demands of this heuristic. The third screenshot is from OmmWriter

Dana, an example of calm-augmented calming technology. The OmmWriter user interface is

very minimalistic, and offers no visual distractions, possibly making concentrating on the task

easier.

4.5 Testing heuristic 3: Acknowledge human interpretations of time passing by

To see if this heuristic is valid, one should test if acknowledging a human interpretation of

time passing by, and distracting users while they have to wait, makes users feel less stressed.

The requirements for this test are:


The TRE must be able to (seem to) perform a dynamic system task. The user interface must be able to show a progress bar. 2 types of progress indicators:

o one that displays progress according to actual progress.o one that displays progress with an acceleration near the end.

The user must be able to set the type of indicator to be enabled. The system must incorporate a means to distract the user while displaying the progress

bar.

The distraction must not obscure the progress bar.


The distraction must make time seem faster. The distraction must be interesting to the user. Distracting stimuli should be of average complexity.

To test the effectiveness of this heuristic, one should have users perform a task, and while

performing the task, the user must come to a point where one needs to wait for the system that

is busy with some task that requires completing. The initiation and the progress of the systemtask should be visualized on the screen, so the use of a progress bar is required here.

The progress bar for the system task in the TRE must be able to display the progress of tasks

with dynamic completion conditionsin two ways, so two conditions can be compared with

one another. First, the progress indicator must be able to display progress for tasks with

dynamic completion conditions in accordance to the actual progress made. Second, a progress

bar that is intelligent enough to make it look like progress of dynamic tasks is speeded up at

the end of the process, should be available. This may help reduce stress because people get

more sensitive to delays the longer they wait.It is not important that the progress bar in the

TRE is really linked to task progress, as long as the users think it is.The researcher must be


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able to set the progress bar to display either linear progress or nonlinear progress in a settings

menu.

In future commercial software, the new to develop progress bar should display progress for

dynamic tasks. Processes with static completion conditions can be visualized accurately

enough by regular progress bars, so this heuristic has no added value for them (Harrison et al.,

2007). An example of a dynamic task is copying a batch of files that greatly differ in size.

Because bigger files will be transferred more efficiently than smaller files, and an unexpected

amount of smaller files in the batch can cause a slower filling of the progress bar near the end.

We need to test if deploying intelligent progress indicators can help reduce stress in these

situations.

Another technique that should be implemented is that of distraction. The TRE must offer a

distraction for the users while they wait. The distraction must take away the focus from the

progress indicator, making time appear to go faster. Examples of distractions are exercises

showed on screen, or a small slideshow of images that a user has on his hard disk. Hogans

(1978) conclusion that stimulus complexity affects perception of time duration can be applied

by making distractions of appropriate complexity.

Multiple conditions can be created. In one condition, the progress bar displays linear progress

with or without a distraction. In another condition, the indicator displays progress nonlinearly

with or without adding a distracting. By comparing these conditions researchers will be able

to find out if acknowledging human interpretations of time passing by, and distracting user

while they wait, really helps to reduce stress. When users are seeing an intelligent progress

bar which speeds up near the end- implementing a distraction might be ineffective. For thisprogress bar, it is more important to be watched, and the effect of making time seem go faster

might be diminished when users do not pay attention to the progress bar due to a distraction.

An example of a TRE test situation: The user uploads a document that was edited with the

TRE to a web server and is showed a progress visualization of the upload task in the form of a

horizontal bar that fills up. The user must wait for the task to be completed, and watches the

progress bar, which seems to speed up noticeably near the end of the bar. While the user wait

for the system task to complete, an interesting distraction is shown in the form of a slideshow

of photographs that the users have saved on their hard drives.

4.6 Testing heuristic 4: Use appropriate human tone and emotion

Does using appropriate human tone and emotion help to reduce stress? Reeves and Nass

(1996) already found that users act polite towards user interfaces and expect reciprocity.

According to Moraveji and Soesanto (2012) apologetic and funny messages, and using polite

requests instead of demands should also have a positive effect on how users feel about the

interaction with the interface. To find out if these interface behaviors really help reduce stress,

researchers need to test the use of humor versus of pragmatics and polite requests versus

demands. For a proper test, the user interface of the TRE must satisfy these requirements:


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The user interface must be able to:o Provide pragmatic and polite acknowledgements.o Provide pragmatic and funny acknowledgements.o Provide pragmatic and apologetic acknowledgements.

Optional:

The user interface should be able to act reciprocal.o It must be able to provide useful output to the user.


Politeness theory should be used to avoid threats to the face. The interface should communicate while obeying Grices maxims of Quality,

Quantity, Relevance and Clarity in the polite condition.

To test if applying appropriate human tone and emotion to user interfaces, helps to reduce

stress responses, polite, funny and apologetic conditions should be tested. The politeness

theory, the media equation theory and Grices Maxims (see p. 13-15) can be applied to create

the right conditions for testing this heuristic.

To test the effects of politeness, one must be able to choose between showing the polite type

of wording, or the normal, more pragmatic type. This option will facilitate the creation of the

conditions that can be compared with each other. In the polite condition, all dialogs, help

functions and menus should contain polite wording. The polite type of wording should make

use of the politeness theory and Grices Maxims, and could resemble the following style:

"Please provide a name for this document before saving it", "We are very sorry for the

inconvenience but the application has crashed previously", " It seems you forgot to specify the

file type, please try again". In the pragmatic condition, the type of wording could resemble

this style: "You have not provided a name for this document", "The application has crashed,

an error report has been sent", "Specify a file type before saving".

Testing the effects of using apologetic messages can be done creating a condition in which

feedback messages use apologetic text, making the user feel like they were not the ones

making a mistake. In this condition, the system uses wording like I am sorry, but that action

is not available right now. In the opposite condition, messages are pragmatic: This action is

not available. The effect of using apologetic wording partially overlaps using the polite

condition mentioned earlier, because apologizing can be considered a form of politeness.

The test for the effects of funniness is similar to that for politeness. Fun is defined as what

provides amusement or enjoyment (Merriam Webster Dictionary, 2012). Although fun is a

fuzzy concept, and is subject to interpretation, it should not be hard to induce feelings of

amusement or enjoyment in users through user interfaces. When a message is displayed by the

TRE in the funny condition, the wording should be something that causes amusement. An

example of a funny message is one that YouTube has used: Sorry, something went wrong. Ateam of highly trained monkeys has been dispatched to deal with this situation. Or when a


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user saves a document: Brilliant! You saved the document! or Good! You just saved

another rainforest! It is important to pay attention to the fact that messages that are intended

to be funny can become annoying after seeing them several times. This risk should be

assimilated into the test of this heuristic. Again, researchers can select to display either funny

or normal wording in a general settings menu. Two conditions can then be compared: a

condition with funny worded messages versus one with more pragmatic wording.

Designing a proper test for reciprocity in a word processor like the TRE, is difficult.

Implementing reciprocity requires features that are capable of making the interface provide

the user with valuable outcomes, which is not something a word processor is built for. I have

provided an outline for a test, that can be done separate from the TRE to test the reciprocity

part of this heuristic.

To test the effects of enabling or disabling reciprocity, a task is needed in which participation

of both the user and system is needed. Furthermore, researchers must be able create situations

where users feels like they are of service to the system. At the same time, the software that is

used for this test must be able to offer a situation in which the system can do something

worthwhile for the user as well. Conditions in which the interface does not act reciprocal and

conditions in which it does can then be compared.

An example of a test for the effects of reciprocity on stress levels: Users are asked to free

space on their hard drives by finding files that can be deleted, so the system can perform an

effective defragmentation of the hard drive. When the users have done this, they return to the

defragmentation screen and start the defragmentation. Here, the system will perform a

successful defragmentation and says that system has been made 20% faster. Or, the systemdoes not adhere to the principle of reciprocity and performs the defragmentation, but after

being completed lets the users know that it was not able to achieve any performance

improvements. In this case the users have acted reciprocally, but the system has not, which

violates expectations users have. It is important to explain to the users what the advantage of

defragmentation is in order to create an incentive to start this process.

4.7 Testing heuristic 5: Provide positive feedback to user input and events

The fifth heuristic concerns giving positive feedback when a user successfully completes a

part of the interaction with the user interface. When the user interface interacts with the user

on a more positive tone, the user should feel less stressed. Key here is to refrain from givingfeedback on negative events, such as failures, and to provide positive feedback on (small)

successes.


The user interface must be able to display short positive messages when a usersuccessfully completes a small task.

o The positive messages must be short and encouraging. Researchers must be able to omit negative user feedback from the user interface.


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The positive messages must have a positive effect on the users self-esteem, enhancethe feeling of control and acknowledge conversational norms.

The positive messages should not become patronizing or annoying and should notviolate the politeness theory.

Negative feedback must be phrased as positive as possible.To create a setting in which the user interface provides positive feedback, the TRE must be

fitted with positive messages that are shown when the user succeeds in successfully

completing a (sub)task, such inserting data into a table or submitting a document to a web

server. The positive messages should resemble these wordings: Good job on completing

Well done! Thank you for. These acknowledgements should be given every time a

user successfully completes a certain subtask, but designers must beware of including these

statements in every interaction with the user interface, as this may seem patronizing andbecome annoying to users. Making these acknowledgements appear for a very brief period

may help to reduce the chance of being patronizing or annoying. Furthermore, negative

feedback such as Invalid filename! and Unable to. must be omitted from the user

interface as much as possible, or be rephrased positively. Again, the TRE must also feature

the option to enable or disable the positive and negative messages in a general settings menu.

To test the effects of omitting or rephrasing negative feedback, and increasing the amount of

positive feedback, different conditions must be compared. A condition in which negative

messages are left out and positive messages on success are shown, versus a condition in

which negative mes

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Reducing Stress Factors in User Interfaces