title: The odd-even effect in multiplication: parity rule or familiarity with even numbers?
abstract: This study questions the evidence that a parity rule is used during the verification of multiplication. Previous studies reported that products are rejected faster when they violate the expected parity, which was attributed to the use of a rule (Krueger, 1986; Lemaire & Fayol, 1995). This experiment tested an alternative explanation of this effect: the familiarity hypothesis. Fifty subjects participated in a verification task with contrasting types of problems (even x even, odd x odd, mixed). Some aspects of our results constitute evidence against the use of the parity rule: False even answers were rejected slowly, even when the two operands were odd. We suggest that the odd-even effect in verification of multiplication could not be due to the use of the parity rule, but rather to a familiarity with even numbers (three quarters of products are indeed even).
authors.affiliation: Université Catholique de Louvain, Faculté de Psychologie, Louvain-La-Neuve, Belgium. lochy@neco.ucl.ac.be
authors.forename: A
authors.initials: A
authors.lastname: Lochy
authors.forename: X
authors.initials: X
authors.lastname: Seron
authors.forename: M
authors.initials: M
authors.lastname: Delazer
authors.forename: B
authors.initials: B
authors.lastname: Butterworth
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D008128:Logic; D008297:Male; D008433:Mathematics; D008568:Memory; D008960:Models, Psychological; D011340:Problem Solving; D011578:Psycholinguistics