Strategy development in a block design task. (Intelligence).

1. Introduction

This study was conducted in the general framework of the cognitive psychology of problem solving, where the processes or strategies underlying performance on psychometric tests are analyzed (Carpenter & Just, 1986; Dickes, Houssemand, & Reuter, 1996; Hunt, 1982, 1983; Hunt, Lunneborg, & Lewis 1975; Huteau, 1995; Jones & Torgesen, 1981, Lansman, Donaldson, Hunt, & Yantis, 1982; Lautrey & Huteau, 1990; Pellegrino & Glaser, 1979; Richard, 1996; Royer, 1977; Royer, Gilmore, & Gruhn, 1984; Rozencwajg & Huteau, 1996; Steinberg, 1988).

One way of analyzing the strategies used on intelligence tests consists of observing subjects' behavior while the test is underway, which generally requires adapting the situation to some extent. This approach was used to detect the strategies that subjects implemented to solve Kohs blocks (Beuscart-Zephir & Beuscart, 1988; Rozencwajg, 1991) or to solve the Passalong test (Richard, 1996; Zamani & Richard, 2000). As Royer (1977, p. 33) said, "The approach is to analyze the task directly by manipulating its structural variables rather than indirectly by factor analysing its relationship to other tests."

1.1. The block design task

The task examined here was derived from Kohs blocks, also called the block design task (Kohs, 1923), in which subjects use red and white colored blocks to reproduce two-dimensional square, red and white designs composed of geometric figures (see Fig. 1). Kohs blocks have given rise to a variety of tasks, all based on the same principle (Alexander, 1950; Bonnardel, 1971; Wechsler, 1974).

[FIGURE 1 OMITTED]

This task is interesting for several reasons. It is usually considered to be a general intelligence test which is highly saturated in factor g. Royer et al. (1984), for example, reported a correlation of .80 between Kohs blocks and IQ assessed on Binet's test. Wechsler uses it as a subtest on his child and adult scales, and its correlation to Weschler's overall score is also high. For Royer et al., "it serves, then, as a very good measure of general intelligence, as well as of performance abilities" (p. 1474).