VAS-RRP 2.0

The Visual Analogue Scale for Rating, Ranking, and Paired-Comparison (VAS-RRP) is a new psychometric scale, which can be used to collect rating, ranking, and paired comparison data simultaneously. For more information, please refer to Sung, Y. T.,& Wu, J. S. (2018). The Visual Analogue Scale for Rating, Ranking, and Paired Comparison (VAS-RRP): A New Technique for Measuring Traits.


What’s new in VAS-RRP 2.0?

There are several new features in VAS-RRP 2.0:

  1. We have added an online registration function, which provides spaces for each user to construct their own scales and collect data.
  2. A new tool, Continuous Rating Scale Analytics (CoRSA), has been added to the website. CoRSA provides services for re-scaling the ordinal data (e.g., data from Likert scales or VASs) to interval scores.

If you are the users of VAS-RRP generator and still need to access the previous interface and database, please click here.


Components and formats of VAS-RRP

Typically, a VAS-RRP consists of two components (Fig. 1):

A testlet composed of one or more items to be rated, which may be of one or several semantic types—such as adjectives, nouns, phrases, and sentences—for eliciting respondents’ internal responses, including attitudes, opinions, interests, and so forth.

A continuous rating scale, which is a straight-line continuum of a specified length with descriptors(anchors) at each end. Below is an example of VAS-RRP.

Fig. 1 An example of VAS-RRP


In addition to the typical format, VAS-RRP also functions well as several types of traditional scales:

  • If there is only a single item in a testlet, and the scale is a line continuum, then the VAS-RRP can function as a VAS.
  • If there is only a single item in a testlet, and the continuous scale is collapsed into several categories (e.g., five points of Likert scale), then the VAS-RRP can function as a Likert scale.
  • If there are two items in a testlet, then the VAS-RRP can function as a paired comparison scale.
  • If there are three or more items in a testlet, then the VAS-RRP can function as a ranking scale or multidimensional forced-choice scale (MFC). .

The Usage of VAS-RRP

Take the case of VAS-RRP with a continuous rating scale. While using a VAS-RRP, if there is only a single item in a testlet , the respondent first checks the item and then indicates its appropriate position on the line continuum by dragging and dropping the item onto the scale , which is similar to the response to an item on a typical VAS. If there are multiple items in a testlet , respondents can repeat the procedure described above for a single item several times, until all the items in the testlet are located on the line continuum. During the process, respondents are allowed to move any item freely on the line and to do plenty of comparisons , until the relative positions of all items on the line match up to the respondent’s opinions . Meanwhile, different items in the testlet are not allowed to be marked at the same point, which assures that the VAS-RRP can be used as a comparison method. Therefore, the same number of items for each testlet and the same scale type in the same survey are required.


The scores of each item are calculated on the basis of the coordinates on the line continuum, which are represented by the pixels on the computer screen. Specifically, if x1 and x2 represent the two endpoint coordinates on the continuum, and the respondent indicates an item as x3 , the score is calculated as (x3-x1)/(x2-x1 ) for the item, which ranges from 0 to 1, indicating the level of intensity or strength of the item. Note that linear transformations can be used. For example, scores can be adjusted to fall within the range of [0, 100], or moved horizontally to an interval with 0 as the midpoint, such as [–1, 1]. Because the value for a participant’s response can be any number within the chosen range, a VAS-RRP, like a VAS, can be considered a very fine-grained scale.


Demo of VAS-RRP

We demonstrate how to use VAS-RRP as the scale types below :

1
Demo of the typical case of VAS-RRP

i.e., VAS-RRP with a multi-item testlet and a continuous scale.

2
Demo of the VAS case

i.e., VAS-RRP with a single-item testlet and a continuous scale.

3
Demo of the Likert scale case

i.e., VAS-RRP with a single -item testlet and a discrete scale.

4
Demo of the paired comparison scale

i.e., VAS-RRP with a two-item testlet and a continuous scale.

5
Demo of the ranking / MFC continuous

i.e., VAS-RRP with a multi-item testlet and a continuous scale, or a discrete scale with the number of points the same as the number of items.

6
Demo of the another type

i.e., VAS-RRP with the scale fit the item


What’s CoRSA ?

Although the VAS-RRP can function as various scale types, their response data , no matter whether the data is continuous or discrete , are ordinal. CoRSA , a new analytical tool named the Continuous Rating Scale Analytics , had been developed not only for re-scaling the ordinal continuous data (e.g., data from VASs) to interval scores, but also for the discrete data.