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R A Griggs

Publications and source records attributed to R A Griggs.

5 recordsLinked to original sources
PubMed2001

Elementary, my dear Wason: the role of problem representation in the THOG task.

The present study was concerned with Wason's THOG problem, a hypothetico-deductive reasoning task for which performance over the past 20 years has typically been very poor (< 20% correct). We examined the hypothesis that incorporating a quasi-visual context into the problem statement would make both the binary, symmetric tree structure and solution principle of the THOG task clearer and thus facilitate performance. A version of O'Brien et al.'s (Q J Exp Psychol 42A:329-351) Blackboard THOG problem, that specifies each branch of the tree by describing a specific location for each possible color-shape combination, was used to test this hypothesis. Substantial facilitation was both observed (68% correct) and replicated (73% correct), and it was also shown that it is necessary to provide a representation of both sides of the tree to obtain this level of facilitation. The implications of these results for human deductive reasoning are considered.

Adult↗
PubMed2001

De-confusing the THOG problem: the Pythagorean solution.

Sources of facilitation for Needham and Amado's (1995) Pythagoras version of Wason's THOG problem were systematically examined in three experiments with 174 participants. Although both the narrative structure and figural notation used in the Pythagoras problem independently led to significant facilitation (40-50% correct), pairing hypothesis generation with either factor or pairing the two factors together was found to be necessary to obtain substantial facilitation (> 50% correct). Needham and Amado's original finding for the complete Pythagoras problem was also replicated. These results are discussed in terms of the "confusion theory" explanation for performance on the standard THOG problem. The possible role of labelling as a de-confusing factor in other versions of the THOG problem and the implications of the present findings for human reasoning are also considered.

Cognition↗
PubMed1993

Darwinian algorithms and the Wason selection task: a factorial analysis of social contract selection task problems.

In four experiments with 760 subjects, the present study examined Cosmides' Darwinian algorithm theory of reasoning: specifically, its explanation of facilitation on the Wason selection task. The first experiment replicated Cosmides' finding of facilitation for social contract versions of the selection task, using both her multiple-problem format and a single-problem format. Experiment 2 examined performance on Cosmides' three main social contract problems while manipulating the perspective of the subject and the presence and absence of cost-benefit information. The presence of cost-benefit information improved performance in two of the three problems while the perspective manipulation had no effect. In Experiment 3, the cost-benefit effect was replicated; and performance on one of the three problems was enhanced by the presence of explicit negatives on the NOT-P and NOT-Q cards. Experiment 4 examined the role of the deontic term "must" in the facilitation observed for two of the social contract problems. The presence of "must" led to a significant improvement in performance. The results of these experiments are strongly supportive of social contract theory in that cost-benefit information is necessary for substantial facilitation to be observed in Cosmides' problems. These findings also suggest the presence of other cues that can help guide subjects to a deontic social contract interpretation when the social contract nature of the problem is not clear.

Adult↗
PubMed1976

Semantic memory: a bibliography, 1968-1975.

Semantic memory research is briefly described. Then a bibliography of 105 published references in semantic memory, calendar years, 1968-1975, is presented.

Bibliographies as Topic↗