Hierarchical Ascendant Classification of the EPC and the Scholastic Assessment Test-Recentered reasoning scales

I've focused my energy on the JCCES - RIAS relationship those days. By the way, I'm still in the process of arranging research data on the revision of the Epreuve de Performance Cognitive (EPC) for completing the submission of this project to the test publisher.

In order to study the relationship between the EPC-Revised and the Scholastic Assessment Test-Recentered (SAT-I) used by the College Board during the 1985 to 2005 period, I've performed some Hierarchical Ascendant Classification (HAC) analyses (N = 95). Basically, I've considered two different approaches for applying the HAC: (1) the Ward's method using Euclidian distances, and the (2) Ward's method using Chebyshev's distances. The findings for both cluster analyses were different and yield to complementary evidences. On one hand,  the dichotomy shown by the dendogram indicated that both the EPC-R and the SAT-I Math were linked by nonverbal reasoning, and possibly numerical content --the EPC being prepared with numerical sequences--, as opposed to the verbal reasoning and knowledge of the SAT-I Verbal. On the other hand, the measures were grouped in such manner that the two SAT-I scales appeared with a common link to scholastic reasoning and knowledge while the EPC-R being related to the former by reasoning only.

Participants. The sample of participants consisted in 95 individuals. Of these, 20 (21.05%) were females, 75 (78.95%) were males and all of them indicated to have eventually studied in college. The average age of the sample was 20.73 (SD = 3.01).

Correlations. All three measures were observed to significantly correlate. The correlation between the EPC-R and the SAT-I V was the lowest at .49. The EPC-R and SAT-I V showed a closer relationship with a correlation of .60. Furthermore, the composite SAT-I and the EPC-R correlated at .68.

HAC.