Scaling Methods

1. Scaling Methods

2. Scaling Methods • Two types of scales • Comparative Scales • Compare one object with another • Non-comparative scales • Evaluate each object independently

3. Comparative Scales

4. Comparative scales • Shows relative importance between two objects • Relatively small differences are detected

5. 1. Paired comparison • Respondent is shown a pair of objects • He is asked to select one object that he prefers

6. 1. Paired comparison – Example 1 Que.: I will show pair of brands. Please tell me which brand do you prefer from each pair

7. 1. Paired comparison – Example 1

8. 1. Paired comparison – Example 2 Que.: Allocate a total of 11 to brands shown in each pair

9. 1. Paired comparison • Easy to administer. • Not suitable if number of pairs is large.

10. 2. Constant sum scale • Respondents are shown all objects to be compared at one time. • He is asked to allocate points to each object out of total points – say 100.

11. 2. Constant sum scale - Example Que.:Below are five attributes that you might consider while buying a 4-wheeler. Please allocate a total of 100 points to them. More the points, more important is the attribute to you. You can allocate 0 point if the attribute is not at all important to you.

12. 2. Constant sum scale • Data gives relative importance. • Information on intensity is obtained. • Faster than paired comparison. • Data is either in interval scale or ratio scale.

13. Noncomparative Scales

14. 1. Continuous rating scale • Respondent is asked to mark (X) anywhere on a line. Que.: Please indicate your opinion about work of NGOs by placing (X) at the appropriate location on the line shown below Unfavourable Favourable

15. 2. Itemised rating scale • Respondent is asked to select one category. Que.: Please indicate your opinion about work of NGOs by placing (X) in one of the categories shown below. Unfavourable Favourable Extremely Quite Slightly Neither Slightly Quite Extremely

16. 2. Itemised rating scale • No optimal number of categories. • Depends on respondent’s ability to discriminate among categories. • Generally 5 to 9 categories are included. • 5 points rating scale is popular. • Unbalanced categories when responses are skewed. • Separate category for ‘no opinion’ is desirable.

17. 2. Itemised rating scale

18. 2. Graphic itemised rating scale • Respondents are shown pictures • Used for children.