When principal component solutions are compared across two groups, a question arises whether the extracted components have the same interpretation in both populations. The problem can be approached by testing null hypotheses stating that the congruence coefficients between pairs of vectors of component loadings are equal to 1. Chan, Leung, Chan, Ho, and Yung (1999) proposed a bootstrap procedure for testing the hypothesis of perfect congruence between vectors of common factor loadings. We demonstrate that the procedure by Chan et al. is both theoretically and empirically inadequate for the application on principal components. We propose a modification of their procedure, which constructs the resampling space according to the characteristics of the principal component model. The results of a simulation study show satisfactory empirical properties of the modified procedure. The target groups of achievement are researchers in social science and psychologists in practice; selecting assessment instruments in a given case, the latter can draw from the research-based findings to decide, which measures to purchase and apply to assure assessment of the target characteristics of individuals in treatment the most validly. The potential impacts of the achievement are presumed to reflect in the promotion of the Slovene science international-wide (according to the ARRS classification the achievement was assigned to the group of excellent achievements A''), further research, particularly in the field of developmental psychology and cross-cultural comparisons. The achievement has been presented to the interested public as an original article in European Journal of Research Methods for the Behavioral and Social Sciences, within the doctoral course of the Ph.D., program Studies of Social Science and Humanities, whereas its outcomes have been used in our cross-cultural studies and research on differences in target characteristics among individuals of different ages, and also among various other groups.
F.23 Development of new system-wide, normative and programme solutions, and methods