ERIC Number: EJ1034587
Record Type: Journal
Publication Date: 2014
Abstractor: As Provided
Reference Count: 76
Suppressor Variables: The Difference between "Is" versus "Acting As"
Ludlow, Larry; Klein, Kelsey
Journal of Statistics Education, v22 n2 2014
Correlated predictors in regression models are a fact of life in applied social science research. The extent to which they are correlated will influence the estimates and statistics associated with the other variables they are modeled along with. These effects, for example, may include enhanced regression coefficients for the other variables--a situation that may suggest the presence of a suppressor variable. This paper examines the history, definitions, and design implications and interpretations when variables are tested as suppressors versus when variables are found that act as suppressors. Longitudinal course evaluation data from a single study illustrate three different approaches to studying potential suppressors and the different results and interpretations they lead to.
Descriptors: Statistics, Correlation, Predictor Variables, Regression (Statistics), Statistical Significance, Student Evaluation of Teacher Performance, Summative Evaluation, Graduate Students, Longitudinal Studies, Course Evaluation, Data Interpretation
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Publication Type: Journal Articles; Reports - Research
Education Level: Higher Education; Postsecondary Education
Authoring Institution: N/A