James N. MacGregor

Information processing and insight : A process model of performance on the nine-dot and related problems

The 9-dot problem is widely regarded as a difficult insight problem. The authors present a detailed information-processing model to explain its difficulty, based on maximization and progress-monitoring heuristics with lookahead. In Experiments 1 and 2, the model predicted performance for the 9-dot and related problems. Experiment 3 supported an extension of the model that accounts for insightful moves. Experiments 4 and 5 provided a critical test of model predictions versus those of previous accounts. On the basis of these findings, the authors claim that insight problem solving can be modeled within a means-ends analysis framework. Maximization and progress-monitoring heuristics are the source of problem difficulty, but also create the conditions necessary for insightful moves to be sought. Furthermore, they promote the discovery and retention of promising states that meet the progress-monitoring criterion and attenuate the problem space.

Trust and the Design of Work Complementary Constructs in Satisfaction and Performance

The article presents results that indicate that trust and job design are complementary concepts in understanding outcomes like intention to quit and satisfaction. We conceptualized a workers beliefs that a supervisor can be trusted as being composed of three main elements - beliefs in the supervisors predictability, benevolence and fairness. This was motivated in part by a desire to conceptualize trust in a way that distinguished it from leader-member exchange (LMX) quality. The capacity of this measure of trust to predict self-reported outcomes was then compared with a jobs motivational potential score, as a way of testing the trust measures criterion validity. To do so, the results from two separate surveys were analysed. The first was based on the questionnaire responses of 535 employees in the telephone industry in the province of British Columbia; the second, of 230 service station employees from across Canada. In the studies reported here, supervisor relationships accounted for a significant amount of the variance on a variety of criterion measures. The results also suggested that perceptions of trust act independently of job design factors in affecting the outcome variables of absence, intention to quit, satisfaction and performance. In addition, the results indicated trust to be as important as job design factors in predicting outcomes.

Minimizing User Search Time in Menu Retrieval Systems

The optimal structuring of menu indexes in computerized information retrieval is examined. The number of alternatives per page that minimizes search time is determined as a function of the human and machine factors of search strategy, scanning time, key-press time, and computer response time. For a wide range of conditions, the optimal number of alternatives per page is in the range of from four to eight, with limiting integer values of three and four for exhaustive and self-terminating search, respectively.

Human performance on the traveling salesman problem

Two experiments on performance on the traveling salesman problem (TSP) are reported. The TSP consists of finding the shortest path through a set of points, returning to the origin. It appears to be an intransigent mathematical problem, and heuristics have been developed to find approximate solutions. The first experiment used 10-point, the second, 20-point problems. The experiments tested the hypothesis that complexity of TSPs is a function of number of nonboundary points, not total number of points. Both experiments supported the hypothesis. The experiments provided information on the quality of subjects’ solutions. Their solutions clustered close to the best known solutions, were an order of magnitude better than solutions produced by three well-known heuristics, and on average fell beyond the 99.9th percentile in the distribution of random solutions. The solution process appeared to be perceptually based.

What makes an insight problem? The roles of heuristics, goal conception and solution recoding in knowledge-lean problems.

Four experiments investigated transformation problems with insight characteristics. In Experiment 1, performance on a version of the 6-coin problem that had a concrete and visualizable solution followed a hill-climbing heuristic. Experiment 2 demonstrated that the difficulty of a version of the problem that potentially required insight for solution stems from the same hill-climbing heuristic, which creates an implicit conceptual block. Experiment 3 confirmed that the difficulty of the potential insight solution is conceptual, not procedural. Experiment 4 demonstrated the same principles of move selection on the 6-coin problem and the 10-coin (triangle) problem. It is argued that hill-climbing heuristics provide a common framework for understanding transformation and insight problem solving. Postsolution receding may account for part of the phenomenology of insight.

A model of human performance on the traveling salesperson problem

A computational model is proposed of how humans solve the traveling salesperson problem (TSP). Tests of the model are reported, using human performance measures from a variety of 10-, 20-, 40-, and 60-node problems, a single 48-node problem, and a single 100-node problem. The model provided a range of solutions that approximated the range of human solutions and conformed closely to quantitative and qualitative characteristics of human performance. The minimum path lengths of subjects and model deviated by average absolute values of 0.0%, 0.9%, 2.4%, 1.4%, 3.5%, and 0.02% for the 10-, 20-, 40-, 48-, 60-, and 100-node problems, respectively. Because the model produces a range of solutions, rather than a single solution, it may find better solutions than some conventional heuristic algorithms for solving TSPs, and comparative results are reported that support this suggestion.

When Insight Just Won't Come: The Failure of Visual Cues in the Nine-Dot Problem:

The nine-dot problem is a classic in the field of human problem solving. Cognitive accounts of the problems difficulty have been criticized on the grounds that the experimental methods on which they rely for support involve a qualitative change to the task requirements of the problem. The three experiments reported here utilize visual and visual-procedural hints to examine the notion that its difficulty is rooted in a mismatch between problem shape and solution shape. Experiment 1 demonstrated that a perceptual cue to the shape of the solution in the form of shading gave rise to only minimal improvements in performance; an additional hint about the relevance of the shading gave rise to modest, but not statistically significant, improvements. Experiment 2 replicated these findings against an additional control condition in which a solely verbal hint to violate the perceptual boundary of the problem shape was given. Furthermore, when both the verbal and visual hints were provided, performance improved only slightly. Experiment 3 provided participants with experience in producing the shape of the correct solution in problem variants closely related to the nine-dot problem. Performance on the transfer task, the basic nine-dot problem, remained at floor, however. These data suggest that visual constraint relaxation is unlikely to be the sole process by which the insight required to find a solution is achieved. The results are interpreted in terms of a previously proposed computational model of performance.

Optimizing the structure of database menu indexes: a decision model of menu search

The paper investigates the issue of the optimal number of alternatives that should be placed on database menu pages. A previous search-time model (Lee and MacGregor, 1985) is extended by proposing a criterion-based decision model, which makes predictions about how the number of alternatives affects the search process and the pattern of errors that will result. An experimental test of the model largely supported the predictions and indicated that with naive users the optimal number of alternatives per page is four to five. These values resulted in the shortest search times, the highest success rates, and the highest preference rankings.

Human Performance on Insight Problem Solving: A Review.

The article provides a review of recent research on insight problem-solving performance. We discuss what insight problems are, the different types of classic and newer insight problems, and how we can classify them. We also explain some of the other aspects that affect insight performance, such as hints, analogs, training, thinking aloud, and individual differences. In addition, we describe some of the main theoretical explanations that have been offered. Finally, we present some measures of insight and relevant neuroscience contributions to the area over the last decade.

Spatial and Contextual Factors in Human Performance on the Travelling Salesperson Problem

The travelling salesperson problem (TSP) provides a realistic and practical example of a visuo-spatial problem-solving task. In previous research, we have found that the quality of solutions produced by human participants for small TSPs compares well with solutions from a range of computer algorithms. We have proposed that the ability of participants to find solutions reflects the natural properties of human perception, solutions being found through global perceptual processing of the problem array to extract a best figure from the TSP points. In this paper, we extend the study of human performance on the task in order to understand further how human abilities are utilised in solving real-world TSPs. The results of experiment 1 show that high levels of solution quality are maintained in solving larger TSPs than had been investigated previously with human participants, and that the presence of an implied real-world context in the problems has no effect upon performance. Experiment 2 demonstrated that the presence of regularity in the point layout of a TSP can facilitate performance. This was confirmed in experiment 3, where effects of the internality of point clusters were also found. All three experiments were consistent with a global, perceptually based approach to the problem by participants. We suggest that the role of perceptual processing in spatial problem-solving is an important area for further research in both theoretical and applied domains.