Mean percentage correct for baseline and transfer at each set size for rhesus monkeys trained with ten sample observing response (FR10) or no sample observing response (FR0) in the S/D procedure. Error bars represent SEMs. Note. From Figure 6, “Abstract-concept learning and list-memory processing by capuchin and rhesus monkeys” by A. A. Wright, J. J. Rivera, J. S. Katz, and J. Bachevalier, 2003, Journal of Experimental Psychology: Animal Behavior Processes, 29, p. 191. Copyright 2003 by the American Psychological Association. Adapted with permission.