brm unit ii

8/9/2019 BRM Unit II

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Business Research Methods- Unit II Measurement & Scaling TechniquesMeasurement is the process of assigning numbers to

objects or observations

Scaling is a procedure for the assignment of number to aproperty of objects in order to impart some of thecharacteristics of numbers to the properties inquestion.


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Measurement Scales Nominal Scale

Uses numbers or letters to identify differentobjects .

Eg : A scale to Measure the employment status1) Public sector

2) Private Sector

3) Self employed

4) Unemployed

5) OthersNominal scale does not give any relationshipbetween the variables


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Nominal Scale

Quantitative measure is only frequency of itemsappearing

Measure of central tendency Mode

Statistical Test Chi-square test

Least Powerful scale

Eg: Assignment of numbers to basketball players toidentify them.


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Ordinal Scale

Places events in a particular order Variables in an ordinal scale can be ranked It only gives relative position of the variables Implies greater than or less than Measure of central tendency is median Statistical test Non-parametric methodsEg: Question: Please rank the following mobile telephone

service providers from 1 to 5 with 1 representing themost preferred & 5 representing the least preferred

Airtel _____Hutch _____Idea _____BSNL _____Reliance _____


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Ratio Scale

Has an Absolute zero of measurement

Have zero points & also have equal intervals.

Compares the two variables measured on the scale.

Represents actual amounts of variables.This is the most precise type scale.

Can be subjected to any type of mathematical operation,

Eg: Age, Weight , Money ,height are the common ratioscales


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2. Instrument associated errors

Due to poor questionnaire design, improper selection ofsamples.Adequate space for registering the answers in thequestionnaireAmbiguous questions confusion for respondentsComplicated words & sentences misinterpretation

3. Situational Errors

No proper response if a third person is present during

interviewLocation of interview - public places lack of responseNo assurance on data confidentiality


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4. Measurer as a source

Body language & gestures of the interviewer discourage

certain responses.

Failing to record the full response of the respondent

Inappropriate coding & tabulations

Irrelevant statistical tools


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Bases for classification of scales

Subject orientation

Designed to measure the characteristics of respondents.

Judge the stimulus object present to the respondent.

Ask the respondent to judge some specific objects interms of one or more dimensions

Response form

Categorical Rating(without reference to other objects)

comparative ranking(compares with other objects)


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Bases for classification of scales

Degree of subjectivity

Subjective personal preference choose which person

he favours, which solution he likes.

Non-preference judgments judge which solution willtake fewer resources

Scale Properties

Based on the scale the researcher chooses(nominal,ordinal etc)

Number ofDimensions

Unidimensional scales measures only one attribute

Multidimensional scales measure more than oneattribute.


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Scale construction Approaches

Arbitrary Approach

Scale is developed on ad hoc basis.

Most widely used approach. Consensus approach(Thurstone Scale)

Panel of judges evaluate the items chosen.

Item analysis approach(Likert Scale)

Individual items are tested by a group of respondents.Total scores are calculated.

Analysed on the basis of degree of discrimination.


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Scale construction Approaches

Cumulative scales (Guttmans Scalogram)

Conforming to some ranking of items in ascending or

descending order.

Factor Scales(Semantic Differential scale)

On the basis of inter correlations of items to identify thecommon factors.

Factor analysis is used.


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Important Scaling Techniques

Rating Scale

Ranking Scale


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Rating Scale

Qualitative description of a limited number of aspects

Judge in terms of specific criteria

Like --- Dislike

Above average, average, below average 3 to 7 point scales are used

More the rating, more the sensitivity


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A Classification of Noncomparative Rating Scales

Noncomparative

Rating Scales

ContinuousRating Scales

ItemizedRating Scales

Semantic

DifferentialStapel Likert


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Non-comparative RatingTechniques

Respondents evaluate only one object at a time,and for this reason noncomparative scales areoften referred to as monadic scales.

Noncomparative techniques consist of continuousand itemized rating scales.


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Rating Scale Types

Graphical Rating / Continuous rating Scale

Points are put in a continuum

Indicate rating by tick mark

Like Very

MuchLike

Somewhat

Neutral Dislike

Some What

Dislike Very

Much


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Continuous/Graphic Rating Scale

Respondents rate the objects by placing a mark at the appropriateposition on a line that runs from one extreme of the criterion variableto the other.

The form of the continuous scale may vary considerably.

Howwould you rate Bigbazaar as a department store?

Version 1Probably the worst - - - - - - -I - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Probably

the best

Version 2

Probably the worst - - - - - - -I - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -- - Probablythe best

0 10 20 30 40 50 60 70 80 90 100

Version 3

Very bad Neither good Very good

nor bad

Probably the worst - - - - - - -I - - - - - - - - - - - - - - - - - - - - - -- - - - - - - - - - - - - - - - -Probablythe best

0 10 20 30 40 50 60 70 80 90 100


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Rating Scale Types

Itemized Rating

Presents a series of statements

Respondent selects the test

He is always involved in some friction with hisfellow worker

He is often at odds with one or more of his fellowworkers

He sometimes gets involved in friction

He infrequently becomes involved in friction withothers

He almost ever gets involved in friction with hisfellow workers


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Itemized

Rating Scales

The respondents are provided with a scale that hasa number or brief description associated with eachcategory.

The categories are ordered in terms of scaleposition; and the respondents are required to selectthe specified category that best describes the objectbeing rated.

The commonly used itemized rating scales are theLikert, semantic differential, and Stapel scales.


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Likert Scale (Summated Scale) Evaluates each item on its ability to discriminate

between those with high score and those with lowscore

Respondent indicates degree of agreement ordisagreement with the statements in the instrument

Each response is given a numerical score, indicating

favourableness or unfavourableness and total scorerepresents the attitude


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Likert ScaleThe Likert scale requires the respondents to indicate a degree of agreement

or disagreement with each of a series of statements about the stimulusobjects.

Strongly Disagree Neither Agree Strongly

disagree agree nor agreedisagree

1. Sears sells high quality merchandise. 1 2X 3 4 5

2. Sears has poor in-store service. 1 2X 3 4 5

3. I like to shop at Sears. 1 2 3X 4 5

The analysis can be conducted on an item-by-item basis (profileanalysis), or a total (summated) score can be calculated.

When arriving at a total score, the categories assigned to the negativestatements by the respondents should be scored by reversing the scale.


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Likert Scale Construction

Identify the attitudinal object and delimit it quite specifically.

Compose a series of statements about the attitudinal object thatare half positive and half negative and are not extreme,ambiguous, or neutral.

Establish (a minimum of ) content validity with the help of anexpert panel.

Pilot test the statements to establish reliability for each domain.

Eliminate statements that negatively affect internal consistency.

Construct the final scale by using the fewest number of itemswhile still maintaining validity and reliability; create a balance ofpositive and negative items .

Administer the scale and instruct respondents to indicate theirlevel of agreement with each statement.

Sum each respondents item scores to determine attitude.


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Likert Scale (Multi Item) - Example

1. Bigbazaar is an attractive store.Neither

Strongly Agree Nor StronglyAgree Agree Disagree Disagree Disagree

1 2 3 4 5

2. The service at Bigbazaar is slow.Neither


1 2 3 4 5

3. Bigbazaar has attractive prices.Neither


1 2 3 4 5


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Likert Scale (Summated Scale)

Advantages

Easier than Thurstone Scale

Without panel of judges

More reliable as it considers each item statementand respondent

Limitations

Just gives the difference in attitudes and does notquantify the same


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Semantic Differential Scale

The semantic differential is a seven-point rating scale withend points associated with bipolar labels that have semanticmeaning.

RELIANCE IS:

Powerful --:--:--:--:-X-:--:--: Weak

Unreliable --:--:--:--:--:-X-:--: Reliable

Modern --:--:--:--:--:--:-X-: Old-fashioned

The negative adjective or phrase sometimes appears at the leftside of the scale and sometimes at the right.

This controls the tendency of some respondents, particularly

those with very positive or very negative attitudes, to markthe right- or left-hand sides without reading the labels.

Individual items on a semantic differential scale may bescored on either a -3 to +3 or a 1 to 7 scale.


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Semantic Differential Procedure

Identify the concept to be measured

Generate a list of approximately 7 or 8 bipolaradjectives with an number of positions betweeneach pair. (Subjects lose focus after 8)

Administer the scale and instruct respondents toidentify where, on the continuum between the twoadjectives, their beliefs about the concept lie.

The spaces or positions between the adjectivesbecome categories with a numerical value (e.g.

1=unfavorable and 6=favorable) and responses aresummed to determine attitude.


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Semantic Differential Scale - Example

Service is discourteous 1234567 Service is courteous

Location is convenient 1234567 Location isinconvenient

Hours are inconvenient 1234567 Hours areconvenient

Loan interest rates 1234567 Loan interest rates

are high are low


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Stapel Scale

The Stapel scale is a unipolar rating scale with ten categoriesnumbered from -5 to +5, without a neutral point (zero). Thisscale is usually presented vertically.

Bigbazaar

+5 +5

+4 +4+3 +3

+2 +2X

+1 +1

HIGH QUALITY POORSERVICE

-1 -1

-2 -2

-3 -3-4X -4

-5 -5

The data obtained by using a Stapel scale can be analyzed in the

same way as semantic differential data.


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Basic Noncomparative Scales

Scale Basic Characteristics Examples Advantages Disadvantages

Continuous Place a mark on a Reaction to TV Easy to construct Scoring can beRating Scale continuous line commercials cumbersome

unless computerized

ItemizedRating Scales

Likert Scale Degree of agreement on a Measurement of Easy to construct, More time1 (strongly disagree) to attitudes administer, and consuming5 (strongly agree) scale understand

Semantic Seven-point scale with Brand, product, and Versatile Difficult to construct;Differential bipolar labels company images appropriate bipolar

adjectives

Stapel Scale Unipolar ten-point scale, Measurement of Easy to construct; Confusing and-5 to +5, without a neutral attitudes and Administered over difficult topoint (zero) images telephone apply


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Ranking Scale/Comparative scale

Make comparative/relative judgments

Approaches

Method of paired comparison

Method of rank order


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Paired Comparisons

Description - Paired comparison scales ask arespondent to pick one of two objects from a set basedupon a given criterion

Example - Which of the following pairs that is mostimportant to you while selecting a toothpaste?

a.Fights Decay b.Affordable

a.Affordable b.Longer germ protection

a.Longer germ protection b.Fights decay


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Method of Paired Comparison

Respondent expresses the attitude by making choicebetween two objects

Number of comparisons (N) to be made depend uponnumber of objects (n)

N = n/2 (n-1) If n= 10, N = 45 Reduce possible comparisons by sample survey Paired Comparison can be converted to interval data

by the Thurstones Law of Comparative Judgment &Guilfords composite standard method


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Rank-Order Scale

Description - respondent is asked to judge one itemagainst another.

Example - Rank the following brands of cereal according

to your preference (1=most preferred).

__ Kelloggs Corn Flakes

__ Rice Krispies

__ Wheaties

__ Kelloggs Raisin Bran ...


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Other TypesConstant Sum Scale

This technique requires the respondent to divide agiven number of points, typically 100, among two ormore attributes based on their importance

Constant sum scales are used more often than pairedcomparisons because the long list of paired items isavoided

Characteristics of a super market Number of points

It is conveniently located _____

Sales persons are cooperative _____

The ambience is pleasing _____

Parking facility is adequate _____

100 points


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Cumulative Scale /Guttmans Scalogram Scale

Here the respondent checks each item with which they agree

The items are constructed so that they are automaticallycumulative if you agree to one, you probably agree to all of theones above it on the list

Can be a good way to gauge how people feel about controversial

topics Requires care when writing so that it doesnt seem leading

Example :

Please check each statement that you agree with:

__ Willing to permit immigrants to live in the U.S.

__ Willing to permit immigrants to live in your community.

__ Willing to permit immigrants to live in your neighborhood. __ Willing to have an immigrant as a next door neighbor.

__ Willing to let your child marry an immigrant.


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Differential Scale (Thurstone Scale)

Uses consensus approach

Method used in measuring attitude on single dimension

Used to measure the issues like war, religion, etc.


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Thurston Scales

Items are formed (80 to 100)

Items are given to a group of judges

Panel of experts assigns values from 1 to 11 toeach item

Judges favour or disfavour them

All items that have consensus are selected otheritems eliminated.

Mean or median scores are calculated for each

item Attitude comparison made on the basis of this

median.

It is a time consuming method.


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Thurston Scales

Example:Please check the item that best describes your level

of willingness to try new tasks

I seldom feel willing to take on new tasks (1.7)

I will occasionally try new tasks (3.6)

I look forward to new tasks (6.9)

I am excited to try new tasks (9.8)


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Surfing the Internet is

____ Extremely Good

____ Very Good

____ Good

____ Bad

____ Very Bad

____ Extremely Bad

Surfing the Internet is

____ Extremely Good

____ Very Good

____ Good

____ Somewhat Good

____ Bad

____ Very Bad

Balanced Scale Unbalanced Scale

Balanced and Unbalanced Scales


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Criteria for good measurement

Reliability

Validity

Sensitivity

Relevance Versatility

Ease of response


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Scale Evaluation

Scale

Evaluation

ReliabilityValidity

Test-Retest

Internal

ConsistencyAlternative

Forms Construct

Criterion

Content


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Reliability

When the outcome of the measuring process is

reproducible then the measuring instrument is reliable.

Eg: If a coffee vending machine gives the samequantity coffee every time, then measurement of

coffee vending machine is reliable

Ability to obtain similar results by measuring an object,trait or construct with independent but comparablemeasures

Example: Do both CAT and MAT scores measure the

candidates performance?Reliability can be defined as the degree to which the

measurements of a particular instrument are free fromerrors and as a result produce consistent results.


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Evaluation of reliability

1. Test retest reliabilityIf the result of a research is the same even when it is conductedfor the second or third time it confirms the repeatability aspect.

Eg : If 40% of the population say that they do not watch moviesand when the research is repeated after sometime and the resultis the same, then measurement process is said to be reliable.

2. Equivalent form reliabilityTwo measurement scales of similar nature are to be developed.

Eg : two types of questionnaires to measure the same aspect withcompletely different questions, with a time gap of2 weeks.

The reliability is tested by measuring correlation of the scoresgenerated by two instruments.


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3. Internal consistency

When the data give the same results even after some

manipulations.

Eg: After a research result is obtained for a particular study, the result can be split into two parts, the result of onepart can be tested against the result of the other , if they are consistent then the measureis reliable.


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Validity

Ability of a scale or measuring instrument to

measure what it is intended to measure can betermed as the validity of the measurement.

Measuring the morale of the exam based onabsenteeism alone.

Test for validity

1. Face validity

Collective agreement of the experts andresearchers on the validity of the measurementscale.

Weakest form of validity


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2.Content Validity

Adequacy in the selection of relevant variables formeasurement.

The scale that is selected should have required

number of variables for measurement.Eg Measuring all government schools have adequatefacilities.

Scale developed to measure aspects like numberof classroom, number of qualified staff on roll, capacity

of the playground etc.


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3. Criterion-related validity

It relates the degree to which measurement instrumentcan analyze a variable that is said to have a criterion.

If a new method is developed , one has to ensure thatit correlates with other measures of the same construct.

Eg: Length of an object is measured with the help of tape measure ,calipers, ruler & if a new technique isdeveloped then one has to ensure that this newmeasure correlates with other measures of length.

Types

Predictive Validity The extent to which the future level

of a criterion variable can be predicted by the currentmeasurement on a scale.

Eg: A scale measuring the future occupancy of anapartment.


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Concurrent validity It is related with the relationship between the predictor variable

& criterion variable. Both the predictor variable & criterion variable are measured on

the same scale. A measure is used to predict something assessed at the same

point in time

4.Construct ValidityIt refers to the degree to which measurement instrument

represents & logically connects through the underlying theory.It assesses the underlying aspects relating to behaviourIt measures why a person behaved in a certain way rather

than how he has behaved.Assessment of how well the instrument captures the

construct, concept, or trait it is supposed to be measuring


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Sensitivity

Sensitivity refers to an instruments ability to accurately

measure variability in stimuli or responses.

Sensitivity is not in high in instruments involving Agreeor Disagree

It will be high in Strongly agree, mildly agree, mildlydisagree, none of the above

Generalizability

The amount of flexibility in interpreting the data indifferent research designs.

Relevance

Appropriateness of using a particular scale.


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Examples OfCategory (Itemized) Rating

Scales1. Balanced, forced-choice, odd-interval scale focusing on an attitude toward a

specific attribute

(1) How do you like the taste of Classic Coke?

___ ___ ___ ___ ___

Like It Like it Neither Like Dislike It Strongly

Very Much Nor Dislike It Dislike It

2. Balanced, forced-choice, even-interval scale focusing on an overall attitude

(2) Overall, how would you rate Ultra Brite Toothpaste?

___ ___ ___ ___ ___ ___

Extremely Very Somewhat Somewhat Very Extremely

Good Good Good Bad Bad Bad


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3. Unbalanced, forced-choice, odd-interval scale focusing on

an overall attitude

(3) What is your reaction to this advertisement?

___ ___ ___ ___ ___

Enthusiastic Very Favorable Favorable Neutral Unfavorable

4. Balanced, non-forced, odd-interval scale focusing on a specific attribute

(4) Howwould you rate the friendliness of the sales personnel at Searsdowntown store?

__ __ __ __ __ __ __ __

Very Moderately Slightly Neither Slightly Moderately Very Dont

Friendly Friendly Friendly Friendly Unfriendly Unfriendly Unfriendly KnowNor Un-

Friendly

Examples OfCategory (Itemized) Rating

Scales


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