The Design of Everyday Things

Design

Psychology (POET)

Psychopathology

designing for people

• Create a good conceptual model - controls should look like they control something

– (problem space reflected in the solution space)http://www.baddesigns.com/doors.html

• Make things visible

– e.g. faucet that doubles as a shower controlhttp://www.baddesigns.com/shower1.html

• Mapping - one to one, spatial

• Feedback.... ATM example

Visibility• User needs visual and oftentimes auditory

indication that the system is behaving properly– vi takes keystrokes without any indication – turning off my iPod

• Natural mapping between objects allows the users to complete a task without consciously figuring out how the system works.http://www.baddesigns.com/knife.html

Mapping• The relationship between two or more things

http://www.baddesigns.com/manylts.html– Spatial (stove top)

http://www.baddesigns.com/ranges.htmlhttp://www.baddesigns.com/brake-release.htmlhttp://www.baddesigns.com/boombox.html– Cultural

http://www.baddesigns.com/spigot.html

Ever try to control a remote-controlled car? Coming toward you?

Execution and Mental Models• Providing a good conceptual model of how something

works, helps the user to operate a device properly http://www.baddesigns.com/dorothy.html

• Each person may have a different mental model of how to complete some task. People who grew up on analog watches...http://www.baddesigns.com/lampsw.html

• Design has to be a common model for all.http://www.baddesigns.com/parking.html

People as Explanatory Creatures

• Learned Helplessness - pg. 42 - self blame• Taught Helplessness - self blame brought on by

years of dealing with bad design

http://www.baddesigns.com/path.htmlhttp://www.baddesigns.com/sidewalk.htmlhttp://www.baddesigns.com/numbers.html

7 stages of actionWhat we’d like• form the goal

Acting• form the intention (action toward a goal)• specify the action (without ambiguity)• execute the action (no fear of failure)

Feedback• perceive the state of the world (feedback)• interpret the state of the world (what feedback

means)• evaluate the outcome (degree of success)

• Information is in the world - pg. 56 - knowledge of and knowledge how - navigating a map, using a keyboard, opening a door, etc.

http://www.baddesigns.com/dontgo.html

• Great precision is not required - pg. 58 - GUIs need not detail every move nor give power over every variable (MS Word mystery colors)

http://www.forbes.com/asap/2001/0528/016a.html

• The power of constraints - pg. 60http://www.baddesigns.com/slippery.html (push or turn?)

http://www.baddesigns.com/faucet2.html

• The conspiracy against memory - how many passwords do you need? How many numbers are you expected to remember?http://www.baddesigns.com/airpark.htmlhttp://www.baddesigns.com/streetsn.html

who is at fault for user error?• how well did the designer constrain the user?

http://www.baddesigns.com/coffee_rs2.html• users often blame themselves, when it is the

designer’s fault• design must anticipate user error• an important action must be reversible

http://www.baddesigns.com/phone.htmlHow many times have you left your headlights on?

Left the refrigerator door open? Programmed the microwave for 120 minutes? Recorded the wrong TV program?

it’s all in the specs

• immerse yourself in the problem space

• test during the entire dream curve with the user in mind

social pressure• putting aesthetics first - designer buildings,

designer anything– designers are not typical users / users are not

designers

• creeping featurism

so how much will it cost?

• maintenance is usually 80% of the total cost. Saving that is free money.

• design and testing are often cut to reduce costs, producing the opposite effect!