Appendix A.
Description of cognitive variables and their sources
| Variable | Description | Source |
|---|---|---|
| Reasoning | ||
| Matrix Reasoning | Determine which pattern best completes the missing cell in a matrix |
Raven (1962) |
| Shipley Abstraction | Determine the words or numbers that are the best continuation of a sequence |
Zachary (1986) |
| Letter Sets | Identify which of five groups of letters is different from the others |
Ekstrom et al. (1976) |
| Spatial Visualization (Space) | ||
| Spatial Relations | Determine the correspondence betwee a 3-D figure and alternative 2-D figures |
Bennett et al. (1997) |
| Paper Folding | Determine the pattern of holes that would result from a sequence of folds and a punch through folded paper |
Ekstrom et al. (1976) |
| Form Boards | Determine which combinations of shapes are needed to fill a larger shape |
Ekstrom et al. (1976) |
| Memory | ||
| Logical Memory | Number of idea units recalled across three stories |
Wechsler (1997b) |
| Word Recall | Number of words recalled across trials 1 to 4 of a word list |
Wechsler (1997b) |
| Paired Associates | Number of response terms recalled when presented with a stimulus item |
Salthouse et al. (1996) |
| Speed | ||
| Digit Symbol | Use a code table to write the correct symbol below each digit |
Wechsler (1997a) |
| Letter Comparison | Same/different comparison of pairs of letter strings |
Salthouse & Babcock (1991) |
| Pattern Comparison | Same/different comparison of pairs of line patterns |
Salthouse & Babcock (1991) |