MGT-491 QUANTITATIVE ANALYSIS AND RESEARCH FOR MANAGEMENT

1. Session 11 MGT-491QUANTITATIVE ANALYSIS AND RESEARCH FOR MANAGEMENT OSMAN BIN SAIF

2. Summary of Last Session • Measurement and Scaling • Nominal scale • Ordinal scale • Interval scale • Ratio scale • Errors in Measurement • Commonly used scales in business research

3. Response Methods • Response methods / variability methods include; • Rating techniques • Ranking methods • Paired comparisons • Rank order scaling approach.

4. Rating Scales • A rating scale is a measuring instrument that requires the person doing the rating to assign the person or object being rated to some point along the continuum or in one of the ordered set of categories.

5. Rating Scales (Contd.) • Rating scales are used to judge properties of objects without reference to similar objects. • These rating may be in such forms as ‘like-dislike’, ‘approve-indifferent-disapprove’. • There are many types of rating scales that are used in practice, differing in the fineness of distinction they allow.

6. Rating Scales (Contd.) • In general rating scales are; • Graphic • Itemized • Comparative

7. Ranking scales • A respondent directly compares two or more objects and make choices among them. • When large number of objects are involved choice becomes ambiguous. • The ambiguity can be voided by using paired comparison,

8. Ranking scales (Contd.) • Widely encountered is the situation where a respondent is asked to select one as the ‘best’ or ‘preferred’. • When dealing with only two choices, this approach is satisfactory.

9. Ranking scales (Contd.) • But it may often result in the ‘vote splitting’ phenomenon when the respondent is asked to select the most preferred among three or more choices.

10. Method of paired comparisons • With this technique the respondent can express his attitudes in an unambiguous manner by making a choice between two objects. • Example; • A typical example Is product testing study where a new flavor of soft drink is tested against an established brand.

11. Method of paired comparisons (Contd.) • In the general situation there are often many more than two stimuli to judge, resulting in a potentially tedious task for the respondents (there will be n(n-1)/2 judgments, where n is the number of stimuli).

12. Method of paired comparisons (Contd.) • Using of these n(n-1)/2 judgments simultaneous evaluation of all stimuli objects is not possible in a simple manner. • Thurstone developed an analytical procedure called ‘ law of comparative judgments’ to scale paired comparison data.

13. Method of rank Order • Another comparative scaling approach is to ask respondents to rank their choices. • If 5 items are chosen out of 10 , then only 5 should be ranked.

14. Method of rank Order (Contd.) • This method is faster than paired comparisons and is usually easier and more motivating to the respondent. • On the negative side, there is some doubt regarding how many stimuli may be handled by this method.

15. Method of rank Order (Contd.) • Less than five objects can usually be ranked easily, but respondents may grow quite careless in ranking, say, ten or more items.

16. Method of successive intervals • Neither the paired comparison nor the rank order method is particularly attractive when there are a large number of items to choose. • Under these circumstances, the method of successive intervals is sometimes used.

17. Method of successive intervals (Contd.) • In this method , the subject is asked to sort the items into piles or groups representing a succession of values. • An interval scale can be developed from these sorting's.

18. Quantitative Judgment Methods • These include; • Direct Judgment methods • Fractionation • Constant sum method

19. Direct Judgment Method • The respondent is required to give a numerical rating to each stimulus, with respect to some designated characteristics. • In the unlimited type, the respondent may choose his or her own number in graphical method to position the rating on a line • I-----------------------------------------I

20. Direct Judgment Method (Contd.) • In the limited type, the respondent has limited choice, as given by the researcher. • I 1 I 2 I 3 I 4 I IIIIIII 12 I

21. Fractionation Method • In fractionation method, a number denoting the ratio between two stimuli, with respect to some characteristics, is estimated.

22. Constant Sum Methods • Constant sum methods are used to standardize the scale across respondents by requiring them to allocate a given total score (say 100) among the stimuli ( total adds up to a constant and hence the name).

23. Scale Construction Techniques • This refers to construction of sets of rating scales (questionnaires) which are carefully designed to measure one or more aspects a person’s belief or attitudes. • Scale construction methods are judgment scaling, factor scales and multi dimensional scaling.

24. Judgment Methods • The following are the Judgment methods; • Arbitrary scales • Consensus scaling • Thurstone differential scale • Item analysis • Summated scale • Likert scale • Cumulative scales

25. Arbitrary Scales • It is possible to design arbitrary scales by collecting a number of items that are unambiguous and appropriate to a given topic. • Arbitrary scales are easy to develop and can be designed to be highly specific to the particular case and content.

26. Consensus scaling • In this approach, the selection of items is made by a panel of judges who evaluate proposed scale items and determine; • Whether the item belongs in the topic area • Its ambiguity • The level of attitude that the scale item presents.

27. Thurstone differential scale • This is a form of consensus scaling. • This scale is constructed using consensus of a panel of judges with equal intervals appearing on the scale. • It is widely used for attitude measurement.

28. Item Analysis • In this procedure, a particular item is evaluated on the basis of how well it discriminates between persons whose total score is low.

29. Summated Scale • The most popular type of scale using item analysis approach is summated scale. • This consists of a number of statements that express either favorable or unfavorable attitude towards the object of interest.

30. Summated Scale (Contd.) • Each response category is assigned a numerical score to reflect its degree of attitude favorability, and the scores are summed algebraically to measure the respondent’s attitude.

31. Likert scale • This mostly used scale is based on judgment method using an agree- disagree format. • Each category is assigned a numerical score. • The score on the scale are summed up, to get the total score for an individual.

32. Likert scale (Contd.) • Example; • The objectives of the R & D Department of your organization are clearly set. Strongly Disagree Disagree Neutral Agree Strongly Agree 1 2 3 4 5

33. Cumulative Scales • These scales are constructed as a set of items with which the respondent indicates agreement or disagreement.

34. Case v Scaling • The scale uses a model of comparative judgment . If all of a group of subjects prefer A to B and only 60 percent prefer B to C, then Thursone’s model can help develop an interval scale from these stimulus-comparison proportions.

35. Summary of This Session • Response methods / variability methods include; • Rating techniques • Ranking methods • Paired comparisons • Rank order scaling approach. • Quantitative Judgment Methods

36. Thanks