The Interaction Between The Internal—External Locus of Control and Two Methods of College Instruction

This aptitude-treatment interaction study classified 68 subjects as external or internal. Approximately half of the externals (internals) were given a traditional, teacher controlled method of instruction, with the remaining subjects being involved in a contract for grade plan. At the conclusion of an eight week course in introductory psychology, all subjects were given a 75 item multiple choice achievement posttest. Analysis of covariance was used to test the hypothesis of an interaction between I-E and method of instruction. A strong disordinal interaction was found, with internals performing better under the contract plan and externals performing better under the teacher controlled method. Implications of the results and the role of moderator variables in aptitude-treatment interaction research were discussed.