Measurement of variable& scaling

How are variables measured?Office deskDemographic dataAbsenteeism (decision making when who is

to be fired?)Blood pressure, height, weight.Perception, feelings and attitude

(subjective)

Operational Definition or Operationalizing the ConceptWay of measuring abstract things to observable

characteristics and behaviour.Concept: ThirstyDrink plenty of fluids

To determine the thirst levels of each individuals by measuring the quantity of fluid they consume to quench their thirst

Mc Cleland’s theoryNeed of AchievementNeed of PowerNeed of Affiliation

Need of AchievementMeasure?

What behavioral dimension is observed within people driven by high motivation?

1. Work round the clock or driven by work.2. Unwillingness to relax3. Work on their own4. Challenging job but not too challenging

where probability of success is low5. Progress by getting feedback

Dimension 1: Work round the clockWorking all the time( number of hours

worker in a day)Persevere even in face of some setbacks( nos. of setbacks experienced in task)Reluctance to take time off ( how frequently

time off and for what reasons)

Dimension 2: Unwillingness to relaxHow often you think about work when you

are away from workplace?What are your hobbies?How do you spend your time when you are

away from the workplace?

Continuum of who relax very well to who relax very little

Dimension 3: Work on their own No patience with ineffective people and are

reluctant to work with others

Impatience with ineffectiveness

Dimension 4: Challenging job but not too challenging Routine or stereotyped job description and

other calling for gradations of challenge built into them

Those to opt for medium degree of challenge would have high achievement orientation

then lower or higher ones

Dimension 5: Progress by getting feedback

Like feedback from superiors and even subordinates

Appreciate both positive and negative by keeping a track on how often individuals

seek feedback from other during a certain period of time-say a month or more.

Continuum of extensive feedback to no feedback

1. To what extent you push yourself to get the work done?2. How difficult do you find it to continue in face of failures or discouraging

results?3. How often do you neglect personal matters because you are preoccupied

by your job?4. How frequently you think about ur job when away?5. To what extent you engage in hobbies?6. How disappointed you feel on not reaching goals you had set for

yourself?7. How much do you concentrate on job?8. How annoyed you get when you make mistakes?9. To what extent u refer to work with a friendly but incompetent to one

who’s competent?10. To what extent u prefer to work yourself?11. To what extent you prefer a job that is difficult but challenging than easy

to routine?12. To what degree you prefer extremely difficult assignment to easy one?13. During 3 months, how often have you sought for feedback from

superiors?14. During 3 months, how often have you sought for feedback from

coworkers?15. How often within 3 months you have checked with your subordinates

that what you are doing in not getting in their way of efficient performance/

16. To what extent would it frustrate you if people did not give you feedback on how you are progressing?

What is operational definition is notNot reasons, antecedents, consequences and

correlatesIt describes observable characteristics

Exercise:Operationalize concept of Learning and Stress

Scalingthe process or result of observing an event or object in order to determine its extent or quantity by comparison with a known unit and then assigning numbers or any other symbols

to characteristic or feature according to some prespecified formal rules.

There are four primary scales of measurement are

Nominal (or categorical) scale Ordinal scaleInterval scale Ratio scale

Nominal Scale

does not express any values or relationships between variables

the only mathematical or statistical operation that can be performed on nominal scales is a frequency run or count

most of the demographic information collected is in the form of nominal scales

categories are mutually exclusive and exhaustive

ExampleAmericanAustralianChineseGermanIndianEvery respondent has to fit any oneExample 1 Gender – male or femaleExample 2 Do you use Fair and Lovely soap?– yes or noExample 3Are you undergraduate, graduate or post graduate?

ExerciseSuggest two variables that would be natural

candidates for nominal scales and set up mutually exclusive or collectively exhaustive categories for each.

Ordinal Scale

categories have a logical or ordered relationship to each other (rank-orders the categories in a meaningful way)permit the measurement of degrees of

difference, but not the specific amount of difference.

only possible to determine whether an object or individual has more or less or equal amount of characteristic in comparison to any other – but NOT what amount of this characteristic

ExampleExample - Let there be 3 students A, B

and C who respectively received 10, 12 and 20 marks in a test.

The ranks would be – A – 1st B – 2nd C – 3rd

The quantitative (numerical) difference

between 1 and 2 is the same as that between 2 and 3.

But the difference between the ranks, 1st and 2nd is NOT the same as that between 2nd and 3rd.

ExerciseDevelop an ordinal scale for consumer

preferences for different brands of beer

Interval Scale

numbers are used to rate and assess objects so that numerically equal distances on the scale represent equal distances in the characteristic being measured

distance between adjacent points on the scale is equal

It helps to compute mean and standard deviation

no true zero in this scale

ExampleLet there be 4 students A, B, C and D who

respectively received 4, 10, 16 and 20 marks in a test.

Is D doubly brilliant than B?Is A’s brilliance a quarter that of C’s?The quantitative (numerical) difference between

A’s marks and B’s is the same as that between B’s and C’s

The quantitative (numerical) difference between C’s marks and D’s is thrice that between B’s and C’s.

ExerciseDevelop Achievement motivation on the

interval scale

Ratio Scale

This scale consists not only of equidistant points but also has a meaningful zero point

most sophisticated of scales, since it incorporates all the properties of nominal, ordinal and interval scales

Example(1) Temperature measured in degrees Kelvin is a ratio

scale. because absolute zero = meaningful zero point

0° K on the Kelvin scale = – 273.15 °C on the Celsius scale

(2) If we ask 2 respondents their ages, difference between any two years would always be the

same‘zero’ would signify the absence of age or birth Hence, a 100-year old person is indeed twice as old as a

50-year old one. Sales figures, quantities purchased and market share

are all expressed on a ratio scale. (4) most commonly when respondents are asked for their

age, income, years of participation, etc.

Exercise Mention one variable for each of the four

scales in the context of a market survey and explain how or why it would fit into the scale.

Rating ScalesDichotomous scale Elicits a Yes or No answer (nominal)Category scale Multiple items to elicit a single response

(nominal)Likert Scale Strong subjects on 5 pt scale SD 1 D2 N3 A4 SA5

Semantic DifferentialBipolar attributes identified at extremes of the

scale(interval)Responsive__ __ __ __ __ __ __UnresponsiveNumerical 5pt or 7pt scaleExtremely pleased 7 6 5 4 3 2 1Extremly

DispleasedItemized rating scale : 5 or 7 pt scale.

Balanced scale with a neutral point( unlikely & likely)

Fixed or constant sum scaleChoosing the Toilet soap:1. Fragrance __2. Color __3. Shape __4. Size __5. Texture of Lather _______________________Total Points 100_____________________

Stapel Scale: Simultaneously measures direction and intensity (interval)

Supervisor attributeThe picture of Sony TV is clear -5 -4 -3 -2 -1 clear +1 +2 +3 +4 +5Graphic Rating ScaleHow would you rate Sony TV on the following

scale?(ordinal)Type I: Extremely bad_________________________Excellent

Consensus or Thurstone Equal Appearing Interval scale

Multidimensional scaling- conjoint analysis

Ranking ScalesOrdinal natureThey do not give definitive clues

Paired comparisonthe respondent is asked to

select one of two items as the preferred or less preferred one according to some criteria.

Example – For each pair of TV indicate which one would you choose for your home viewing

Aiwa Akai LG Samsung

Sony

Aiwa ---

Akai ---

LG ---

Samsung

---

Sony ---

Forced ChoiceExample – Rank the following brands of TV as

per your preference for home viewing (1 as the best and 5 as the worst).

Aiwa _____Akai _____LG ____Samsung _____Sony ______

Comparative Scaledeals with direct comparison of objects or

individualsdata collected is interpreted in relative termsdata have only ordinal or ‘rank’

characteristics More Useful About same Less

Useful 1 2 3 4 5

Many changes continue to occur in the healthcare industry. Because of increased competition for patients among providers and the need to determine how providers can better serve their clientele, hospital administrators sometimes mail a quality satisfaction survey to their patients after patient is released. The following types of questions are sometimes asked on such a survey. The questions will result in what level of data measurement?

1. How long ago you were released from the hospital?2. Which type of unit were you in for most of your stay?_Coronary Care_Intensive Care_Maternity Care3. In choosing hospital, how important was the hospital’s location?Very Important, somewhat important, not very Important, not at all important4. How serious was your condition when you were first admitted to the

hospital?_critical _serious _Moderate _minor5. Rate skill of the doctor:_excellent _very good _good _fair _poor6. Rate one to seven on nursing care poor 1 2 3 4 5 6 7 excellent

Goodness of Measures Accurately measure Without redundancy Differentiate relevant and irrelevant things

1. Reliability2. Validity

ReliabilityMeasures without bias, consistent across time

and various items in instrumentTest-retest reliability (across time)Parallel-reliability( changes in wordings and

sequence)Interitem Consistency Reliability (Cronbach’s

Coefficient) Split-half reliability

ValidityAuthenticity of experimental designCause-effect relationships(internal)Generalizability(external)Content Validity(face validity)Criterion related(Concurrent&

Predictive:difference is clear)Construct Validity(Convergent &

Discriminant)

Thank you