EMPIRICAL CONTRIBUTION TO THE QUESTION OF SEX-DEPENDENT INHERITANCE OF SPATIAL ABILITY

The X-linked recessive gene hypothesis, a theory to predict the mode o f genetic inheritance of spatial ability, was tested using a new Rasch -calibrated space test, the Three-dimensional Cube Test (Gittler, 1990 ). This allowedn solving the homogeneity problem (insufficient unidime nsionality of test material) by which earlier research in this field w as affected. The empirical correlations from our sample of 134 familie s were compared with the theoretically prediced values. Present data d o not corroborate the model; however, the problems of its general fals ification are discussed. The fact that differences in performance in f avour of males exist in the parental generation but not in the filial generation accentuates the importance of environmental factors.