This paper is meant to highlight the occurrence of Simpson's Paradox when using aggregated data obtained from two IEA studies in Israel, while ignoring the effect of a powerful intervening variable in the local context--the ethnicity factor. It will demonstrate faulty conclusions regarding either the absence of relationships between a contextual…

Considered are two commonly used techniques, the interview and word association techniques. Highlighted is a third technique called the repertory grid. This third technique can be used to interpret students' knowledge based on an explicit, psychological theory of human behavior. (Author/CW)