We all know of Discovery Channel’s Shark Week, so the Bunker decided to cater to the Market Research arena and create our 1st Annual “Scale Week.” Each day this week, the Bunker will profile a different scaling technique used in market research modalities. We hope these articles will be useful to anyone looking for a brief overview of a specific scale, or someone who is just looking to explore the various options for their own market research. If you stumble upon this article in hopes of finding Shark Week excitement, and find yourself extremely disappointed, we sincerely apologize. But nonetheless, we encourage you to read on.
Scale #1 – Monday
Constant Sum Scaling is a scaling method used to organize and sort a variety of options. The respondent is presented with a few options and given a number of points to allocate to each option. Aside from being used in surveys and questionnaires, constant sum scaling can also be used in more qualitative settings such as focus groups or in-depth interviews, as a way to spark discussion. Here is a basic example of a constant sum scaling question that might be included in a survey (see below). This particular question tries to uncover buying behavior behind purchasing a vehicle. The respondent is asked to allocate 100 points among 4 key features of purchasing a vehicle based on their importance of each.
By entering the relative value of each feature into the equation, constant sum scaling can be used as a way to understand comparative importance when respondents are presented with multiple options. By adding more points to one feature, the respondent is in a sense taking away from points that could be allocated to other features – as the constant sum is 100 points. Doing this through an online survey and using some additional logic to ensure a sum of 100, creates nice and clean data to analyze.
By placing the respondent in this budgeting mindset, they are forced to make an allocation. The respondent is not allowed to rate every option to the max, as it forces them to base their response proportionally. If a traditional 1-10 scale is used here, the respondent may rate all 4 aspects as a 10 (very important), not giving the analyst the option to determine relativity. However, in this case above, the analyst can come to the conclusion that the respondent views performance of a vehicle as four times more important than safety.
One might argue that the equivalent to straight-lining 10s would be breaking the total points into equal categories (for example: 25/25/25/25 into each aspect above). Sure, they may ultimately choose this even split if they choose, but the constant sum scaling option encourages the respondent to think comparatively before answering, something that should not be taken for granted with the ever-growing need for data integrity in market research.