Concreteness and disagreement: Comment on Pollock (2018)

Pollock (Behavior Research Methods doi:10.3758/s13428-017-0938-y, Pollock, 2018) points out that most memory experiments using abstract and concrete words have a potential confound: Raters express more disagreement, on average, about the rating for an abstract word than for a concrete word, as evidenced by the larger standard deviation of the rating (SDR). Therefore, past demonstrations of the concreteness effect could be explained by the disagreement hypothesis: Words that engender disagreement (i.e., have a larger SDR) are more difficult to remember than those that engender agreement (i.e., have a smaller SDR). Three experiments test predictions of the disagreement hypothesis. In Experiment 1, concreteness (abstract vs. concrete) and SDR size (small vs. large) were factorially manipulated. A concreteness effect was observed for both SDR sizes, but there was no effect of SDR and there were no interactions involving SDR. In Experiment 2, a concreteness effect was observed despite using abstract words with a small SDR and concrete words with a large SDR, the opposite of what the disagreement hypothesis predicts. Experiment 3 replicated Experiment 2 but with a larger set of stimuli. The results offer no support for the disagreement hypothesis.