Scale Construction | Item Reversal, Scale Scores, Reliability, and Metadata

This post discusses how to: (a) use exploratory factor analysis output to determine items to retain on a test; (b) run syntax that reverses items and produces scale scores for a test; (c) calculate reliabilities for scales using retained items. Various tips are provided to make the process more efficient and less error-prone. The example uses SPSS, but many of the ideas would generalise to other statistics packages.

Exploratory Factor Analysis and Scale Construction | R, SPSS, and General Resources

In this post I provide links to resources on exploratory factor analysis and scale construction. Links are provided for conducting exploratory factor analysis in R and in SPSS. Links to academic articles on the topic of exploratory factor analysis and scale construction with an emphasis on psychological applications are provided.

Factor Analysis in R

This post shows an example of running a basic factor analysis in R.

Analysis of a Multiple Choice Test | Getting Started

This post discusses how to perform a basic reliability analysis of a multiple choice test.

Calculating Scale Scores for Psychological Tests

This post discusses how to calculate scale scores for multi-item scales. A lot of psychological research uses multi-item scales (e.g., personality tests, symptoms check lists, surveys, etc.). This post focuses on the issues involved with computing these scale scores.

Verifying How Composite Scores Have Been Computed

This post sets out a procedure for checking how a composite was computed from items. This is particularly useful when working with self-report psychological scales and composite ability tests. Computing total scores for a series of subscales and total scores on personality tests and other self-report inventories can be fiddly business, and errors often arise.

Calculating Composite Scores of Ability and Other Tests in SPSS

Researchers in psychology often have a large number of variables. Science aims for parsimonious explanations of the world. Thus, the challenge is to develop a principled approach to dealing with the multiplicities that arise in psychological research. One common approach is to combine tests that measure similar things into composites. This post looks at how to form composites. The emphasis is on settings where you have multiple ability tests and you want to create a composite ability factor. Also, particular emphasis is given to how to do it in SPSS.