Advantages/Disadvantages of Using Each of the Three Comparative Scaling Techniques

Pared comparison scaling

This is an ordinal level technique where a respondent is presented with two items at a time and asked to choose one. This is the most widely used comparison scale technique. If you take n brands then [n (n-1)/2] paired comparisons are required. A classic example of when paired comparison is used is during taste tests. For example you could have a taste test in which you have someone try both Coke and Pepsi and then ask them which one they prefer.

Another simple example is presented as following.

An entrepreneur is looking at ways in which she can expand her business. She has limited resources, but also has the options she lists below:

• Expand into overseas markets

• Expand in home markets

• Improve customer service

• Improve quality

Firstly she draws up the Paired Comparison Analysis table in Figure 1:

Figure 1: Example Paired Comparison Analysis Table (not filled in):

Overseas Market (A) Home

Market (B) Customer

Service (C) Quality

(D)

Overseas Market

(A) Blocked Out

(Step 3)

Home Market

(B) Blocked Out

(Step 4) Blocked Out

(Step 3)

Customer Service

(C) Blocked Out

(Step 4) Blocked Out

(Step 4) Blocked Out

(Step 3)

Quality

(D) Blocked Out

(Step 4) Blocked Out

(Step 4) Blocked Out

(Step 4) Blocked Out

(Step 3)

Then she compares options, writes down the letter of the most important option, and scores their difference in importance. An example of how she might do this is shown in figure 2:

Figure 2: Example Paired Comparison Analysis Table (filled in):

Overseas Market (A) Home

Market (B) Customer

Service (C) Quality

(D)

Overseas Market

(A) A,2 C,1 A,1

Home Market

(B) C,1 B,1

Customer Service

(C) C,2

Quality

(D)

Finally she adds up the A, B, C and D values, and converts each into a percentage of the total. This gives these totals:

• A = 3 (37.5%)

• B = 1 (12.5%)

• C = 4 (50%)

• D = 0.

Here it is most important to improve customer service...