1. Discuss the relative merits of and problems with:
a) Rating and ranking scales.
Rating Scales
A rating scale is a set of categories designed to elicit information about a quantitative or a qualitative attribute. All rating scales can be classified into one of three classifications. Rating scales are used widely online in an attempt to provide indications of consumer opinions of products. There are many pros and cons for rating scales.
Pros
Commonly used and easily understood by respondents.
Allow respondents to assign items the same.
Cons
Often have a narrow distribution of ratings, which typically fall into an upper band (for instance, most items are considered important when using important scales)
Lead to less differentiation among items, with the possibility that a respondent rates every item identically
Accept great personal variations in response styles (e.g., respondents who never assign the highest rating)
Produce possibly false positive correlations due to individuals' personal variations
Ranking Scales
A Rank Order scale gives the respondent a set of items and asks them to put the items in some form of order. The measure of 'order' can include such as preference, importance, liking, effectiveness and so on. The order is often a simple ordinal structure (A is higher than B). There are several pros and cons for ranking scales as well.
Pros
Guarantee that each item ranked has a unique value.
Cons
Force respondents to differentiate between items that they may regard as equivalent.
Emphasize items earlier in the list, which are more likely to be ranked highest.
Return different results depending on the completeness of the list of items being ranked.
Increase the difficulty of answering disproportionately as choices are added.
Limit the range of statistical analysis available.
b) Likert and Differential Scales
Likert Scale
The Likert Model, developed by Rensis Likert in 1932, attempts to put a quantitative value to...