A beautiful day in the neighborhood: What factors determine the generationeffect for simple multiplication problems?

In four experiments, we examined the generation effect for the free recall of simple multiplication answers. Large-product-size problems showed a cons istent generation-effect advantage over small-product-size problems, except when each answer was generated twice, via two different sets of operands ( Experiment 2). Also, measures of problem-solution time and strategy use acc ounted for the large-product-size advantage. Across experiments, however, s mall-product-size problems (but not large-product-size problems) showed con siderable variation in the size of their generation effect. We discovered t hat solving small-product-size problems via direct memory retrieval increas ed the episodic recall probability of other problems that were near neighbo rs to the generated answer, and we attribute this result to a spreading act ivation mechanism in semantic memory. A measure of neighbor activations, co mbined with RT to solve each problem, accounted for 51% of the observed gen eration-effect variance.