Global perceptual processing in problem solving: The case of the travelingsalesperson

The traveling salesperson problem (TSP) consists of finding the shortest to ur around a set of locations and is an important task in computer science a nd operations research. In four experiments, the relationship between proce sses implicated in the recognition of good figures and the identification o f TSP solutions was investigated. In Experiment 1, a linear relationship wa s found between participants' judgments of good figure and the optimality o f solutions to TSPs. In Experiment 2, identification performance was shown to be a function of solution optimality and problem orientation. Experiment 3 replicated these findings with a forced-pace method, suggesting that glo bal processing, rather than a local processing strategy involving point-by- point analysis of TSP solutions, is the primary process involved in the der ivation of best figures for the presented TSPs. In Experiment 4, the role o f global precedence was confirmed using a priming method, in which it was f ound that short (100 msec) primes facilitated solution identification, rela tive to no prime or longer primes. Effects of problem type were found in al l the experiments, suggesting that local features of some problems may disr upt global processing. The results are discussed in terms of Sanocki's (199 3) global-to-local contingency model. We argue that global perceptual proce ssing may contribute more generally to problem solving and that human perfo rmance can complement computational TSP methods.