An Investigation of Test Bias for Mexican-American College Students.

There has been considerable research activity in recent years concerned with the issue of test bias (Cleary, 1968; Goldman & Richards, 1974; Kallingal, 1971; Stanley, 1971; Temp, 1971). Briefly, test bias may be manifest in two predominant forms. The first occurs when a predictor (or set of predictors) is invalid (or less valid) for certain subgroups. This form of test bias implies inaccurate prediction for some groups but not necessarily systematic underprediction or over-prediction. This type of test bias can be identified by comparison of the correlation coefficients (between predictor and criterion) for different subgroups. The second form of test bias occurs when a predictor test consistently underpredicts or over-predicts the criterion for a subgroup. As Cleary (1968, p. 115) concisely states, ". . . the test is biased if the criterion score predicted from the common regression line is consistently too high or too low for members of the subgroup." Both forms of test bias have been studied with reference to Black-White differences. Stanley and Porter (1967) found the Scholastic Aptitude Test (SAT) a nearly equallyaccurate predictor of college success (GPA) for Blacks as well as Whites in essentially segregated colleges. While the correlations of SAT with GPA were similar for Blacks and Whites, it is clear that the regression systems were quite different. Cleary (1968) found homogeneous regression systems for Blacks and Whites in three integrated colleges. Furthermore, regression intercepts differed in only one of the three colleges. However, it should be noted that the accuracy of GPA prediction appeared to be greater for Whites than for Blacks. Investigations by Temp (1971) and Kallingal (1971) found that regression systems for the prediction of GPA were nonparallel for Blacks and Whites in almost all colleges sampled. These investigators also found that GPA's for Blacks were either accurately predicted or overpredicted when using White-derived regression equations. While the aforementioned investigations are valuable, they do not provide direct information to the issue of test bias for other minority subgroups. Temp (1971, p. 247) states in a footnote, "Most investigations have dealt solely with black students and then the generalizations have been extrapolated to other 'minorities' (i.e. MexicanAmericans, the disadvantaged, low income females, etc.)." There are a number of good reasons why it is hazardous to generalize Black-White comparisons to other groups. Most obvious among the reasons is the issue of bilingualism. In addition, child-rearing patterns and values are not identical in these minority groups. Thus, an investigation of test bias should be conducted separately for every subgroup in question. Although Cleary's definition of test bias is probably most widely used by psychologists and educators, several alternative models of test bias have recently emerged (Cole, 1973; Einhorn & Bass, 1971; Thorndike, 1971). These three models, while distinct from each other, suggest that test bias may reside in the use of tests for decision making as well as in regression systems. Thorndike has noted that minority