Constraints on access in a problem solving context

The effects of previously acquired information on a later problem solving task were explored. Prior research has shown that the acquisition of potentially relevant information is not effective for cuing solutions in a later problem solving task unless subjects are informed of the connection. The present research extends these results and demonstrates that the problem solving failure is not due to subjects’ rejecting the potentially relevant information following retrieval. Rather, the apparent failure to appropriately use previous information is a result of uninformed subjects’ inability to spontaneously access such information. Furthermore, the observed access failure is not reversible by simply informing the subjects of the task connection prior to a second trial. Finally, the results indicate that problem solving failure on a later informed trial is a problem-specific phenomenon that does not generalize to new problems. The implications for contemporary episodic memory paradigms and the role of access in learning theory are discussed.     

The access of relevant information for solving problems

Two issues were investigated concerning the retrieval of recently acquired relevant information for solving riddle problems. First, although earlier research indicated that problem solvers often fail to retrieve relevant information unless they are explicitly informed of its relevance, Bowden (1985) suggested that uninformed subjects would benefit greatly from additional problem-solving time. In two experiments, we found that uninformed subjects solved more problems than did subjects who did not receive the information, but a simple model attributed this difference to these uninformed subjects "catching on" to the information's relevance after solving some problems. Second, the retrieval characteristics were examined by varying the proportion of problems for which clues were given. Informed subjects given clues for only half of the problems benefited (though perhaps not fully) from being informed, without incurring any cost from being misdirected on the unclued problems. The discussion focuses on some ways in which accessing relevant information may affect problem solving.     

Giving up problem solving

How do people decide to abandon a problem? Participants were presented with unsolvable water jar problems, having been accurately informed of the prior probability of solvability. Across three experiments, we discovered effects of prior probability of solvability and of problem size (number of distinct problem states) on measures of effort and confidence. If a problem is more likely to be solvable and allows more problem states, a problem solver spends longer trying to solve the problem. Giving-up decisions are informed by the same judgments of probability of success and costs of solution that inform move-choice in a rational model of problem solving.     

The traveling salesman problem: A hierarchical model

Our review of prior literature on spatial information processing in perception, attention, and memory indicates that these cognitive functions involve similar mechanisms based on a hierarchical architecture. The present study extends the application of hierarchical models to the area of problem solving. First, we report results of an experiment in which human subjects were tested on a Euclidean traveling salesman problem (TSP) with 6 to 30 cities. The subject's solutions were either optimal or near-optimal in length and were produced in a time that was, on average, a linear function of the number of cities. Next, the performance of the subjects is compared with that of five representative artificial intelligence and operations research algorithms, that produce approximate solutions for Euclidean problems. None of these algorithms was found to be an adequate psychological model. Finally, we present a new algorithm for solving the TSP, which is based on a hierarchical pyramid architecture. The performance of this new algorithm is quite similar to the performance of the subjects.     

An investigation of the relationships between problem solving strategies, representation and memory

There has been considerable debate in recent years about the status of “imagery” in problem solving. The present experiment attempts to show that while subjects may employ representational strategies when they first encounter a class of problems, they abandon such strategies as they gain experience with the problems. It does this by asking subjects to answer unexpected questions which are based upon the information which they have just used to solve a problem. The hypothesis, which is supported by the results, is that increasing experience with problems will be paralleled by a decreasing ability to answer unexpected questions. The experiment also shows that such effects are not attributable to a build-up in proactive interference.     

Creativity: A complementary relationship between information demand and success at problem solving

Creativity, intelligence, and problem-solving tasks that varied the explicitness of problem definition and the format for an acceptable solution were administered to 100 subjects. Creativity and intelligence tasks were described as different problem-solving tasks. Two hypotheses that distinguished between concepts of creative and intelligent problem solving were presented and supported. First, the syntactical hypothesis stated that the format of an acceptable solution would define the factor structure of the problem-solving tasks more parsimoniously than the explicitness of the problem definition. The factor structure was interpreted by the type of acceptable solution format. Second, the strategic hypothesis stated that information demanded to define a problem and success at problem solving would interact. Information demanded and success at problem solving did interact producing a complementary relationship with dimensions of creativity but not intelligence. Thus, syntactical and strategic distinctions between creativity and intelligence were obtained.     

Visual scanning during pattern recognition in children and adults

Eye movement and fixation responses of 3- to 6-year-old children and adults were recorded during a pattern recognition task. During familiarization, fixations were more repetitive and less extensive for older subjects. The fixation patterns of older children who were consistently able to solve the recognition problems were like those of the adults. Unsuccessful 4- to 6-year-olds spent more time fixating the modified area of the nonstandard pattern presented in paired comparison with the standard, even though their final decision was false. Thus, preschool children were able to locate relevant visual information even when they did not use this information to solve tasks. The results suggest that visual fixations do not always reflect active attention, and that direct fixations of visual information are clearly not sufficient and may not be necessary for problem solving.     

Error detection processes in statistical problem solving

Problem solvers' error detection processes were studied by instructing 16 subjects to think aloud when solving two statistical problems. The evaluative episodes occurring in subjects' protocols were analyzed into Affirmative evaluation, Direct error-hypotheses, Error suspicion, and Standard check episodes, the last three of which are assumed to cover all main types of error detection processes. Most errors (78%) were found to have contributed to a solution part that triggered some evaluative episode. However, only one-third of the undetected errors had contributed to such a solution part. The Standard check episodes, seen as centrally-invoked, only led to the detection of few errors in proportion to the number of times they were performed. Evidence was found for two types of spontaneous error detections, one occurring abruptly and the other as a result of a more elaborated error detection process, initiated by the solver perceiving the solution as dissatisfying or strange. The perception of a symptom was a fairly reliable source of information about errors. However, subjects often did not manage to detect the error after having noticed a symptom. The closer a relevant Error suspicion episode followed an error, the greater was the probability of detecting the error. Good problem solvers detected a higher proportion of their errors compared to poor problem solvers, probably due to differences in the processes leading up to the triggering of an evaluative episode rather than to differences after the episode had been triggered.     

A production system model for human problem solving

Summary A new production system model was developed for a class of transformation problems, based upon the results of an experiment which evaluated the psychological validity of a noticing order in problem solving. This model specifies how general problem solving heuristics interact with domain knowledge and how possible actions are assembled from externally presented information. The production system may conceptually be divided into three groups: move generation, move evaluation, and move execution productions. The simulation model was evaluated by a second experiment. With a common set of parameter values, good fits were obtained between the predicted and observed data. The significance of individual productions was assessed by running simulations with individual productions deleted. While previous simulations have described subjects' behavior on a single problem, the present model successfully predicted human problem solving in three structurally different problems. The proposed production system thus gives a detailed account of the procedural knowledge that subjects use in transformation problems.     

Memory access: The effects of fact-oriented versus problem-oriented acquisition

This study examined the effects of similarity between the processing of acquisition and the processing of test materials on performance in a problem solving task. Previous work by Perfetto, Bransford, and Franks (1983) demonstrated that uninformed subjects’ failure to utilize relevant acquisition information in a later problem solving task is the result of a failure to spontaneously access such information. The present study demonstrated that spontaneous access can be enhanced when both acquisition and test materials are processed in a similar manner, that is, in a problem-oriented manner. Furthermore, the present findings indicate that the processing similarity leading to enhanced access is specific to particular acquisition and test items, rather than a general problem solving set induced at acquisition and the subsequent testing situation. Results are interpreted within a transfer-appropriate processing perspective.     

Depression and social problem solving.

Twenty depressed patients with major depressive disorder, 20 nondepressed matched control subjects, and 17 patients with anxiety disorders were compared in different measures of social problem solving. Problem solving was assessed with the Means-Ends Problem-Solving Test (Study 1), the solution of personal problems, and a problem-solving questionnaire (Study 2). Results showed that, as predicted, depressed subjects suffered from a deficit in problem solving in all three measures. The majority of these deficits were also displayed by the clinical control group rather than being specific to a diagnosis of depression. However, depressed subjects produced less effective solutions than did normal and clinical control subjects. The results suggest that depressed and anxious patients may have difficulties at different stages of the problem-solving process.     

Achievement motivation and problem solving

Abstract.— The relationships between achievement motivation and problem solving were discussed. It was suggested that problem solving may be differentially related to achievement motivation in high and low ability groups. In a group of 46 male students, scoring high on a test of intellectual flexibility, a positive relationship was found between a projective measure of fear of failure and solution of the Hatrack Problem. In a group of 49 male subjects with low flexibility scores, fear of failure was negatively related to problem solving. The results were taken to indicate that the ability measure represented general self confidence and expectancy. Thus subjects with high self confidence might attempt to avoid failure by trying hard to succeed, while a more probable strategy for subjects with low expectancy would be to exert little effort. A test of this hypothesis was made by analyzing a measure of overt activity in the Hatrack situation across high/low motivational and ability groups. Whereas in the high ability group subjects with high fear of failure showed a high level of activity, high fear of failure subjects in the low ability group showed a low level of activity, thus supporting the hypothesis.     

Priming problem solving with conceptual processing of relevant objects

In the present study, the author explored the effect of processing relevant information on producing solutions to brief insight problems. She hypothesized that the conceptual processing of objects relevant to the target solution would facilitate that solution relative to unrelated objects or the shallow processing of words. The author also explored the effect of knowledge of the relationship between the initial object-processing task and the problem-solving task. The results showed that participants who conceptually processed objects related to the target solution (Experiment 1), but not those who shallowly processed words related to the target solution (Experiment 2), were more likely to produce the solution relative to the control; and knowledge of the relationship between objects and solutions made no difference in the frequency of target solutions produced. The results of Experiment 3 showed that conceptual processing of an object could prime a nondominant solution for an ambiguously worded problem. Taken together, the results of the studies supported the effect of conceptual processing on facilitating insight in problem solving.     

The recall of relevant and incidental dimensional values as a function of perceptual salience, congitive set, and age.

In two experiments, subjects were presented an array of compound stimuli consisting of values from four, salience-assessed dimensions. Solution to an initial problem required recall of the array locations of values from only the most salient dimension. In addition to perceptual salience, instructions designed to establish cognitive sets for remembering value locations of certain dimensions were varied to explore the roles of these perceptual and cognitive variables in determining recall. In Experiment I, which involved subjects from grades kindergarten, third, and sixth, older subjects recalled more incidental as well as relevant information than younger subjects, and although instructions to remember values of a less salient incidental dimension facilitated their recall, the same instructions also facilitated the recall of values of a more salient incidental dimension even though no reference was made to those values. In Experiment II, adult recall of both relevant and incidental information was affected by instructions about differing numbers and types of dimensions. Adults and the oldest children did not differ in total information recalled, and there was no evidence for an increase with age in the cognitive ability to select only that information that was relevant to solving the initial problem. The results were discussed in terms of developmental changes in memory capacity and the absolute salience of the task information.     

Insightful problem solving and emulation in brown capuchin monkeys

We investigated problem solving abilities of capuchin monkeys via the “floating object problem,” a task in which the subject must use creative problem solving to retrieve a favored food item from the bottom of a clear tube. Some great apes have solved this problem by adding water to raise the object to a level at which it can be easily grabbed. We presented seven capuchins with the task over eight trials (four “dry” and four “wet”). None of the subjects solved the task, indicating that no capuchin demonstrated insightful problem solving under these experimental conditions. We then investigated whether capuchins would emulate a solution to the task. Seven subjects observed a human model solve the problem by pouring water from a cup into the tube, which brought the object to the top of the tube, allowing the subject to retrieve it. Subjects were then allowed to interact freely with an unfilled tube containing the object in the presence of water and objects that could be used to solve the task. While most subjects were unable to solve the task after viewing a demonstrator solve it, one subject did so, but in a unique way. Our results are consistent with some previous results in great ape species and indicate that capuchins do not spontaneously solve the floating object problem via insight.     

Global vs. local information processing in visual/spatial problem solving: The case of traveling salesman problem

Human visual/spatial problem solving often requires both global and local information to be processed. But the relationship between those two kinds of information and the way in which they interact with one another during problem solving has not been thoroughly discussed. In the particular setting of solving the traveling salesman problem (TSP), we investigated into the relative roles of global and local information processing. An experiment was conducted to measure the importance of global information and the possible constraints of global information processing on search. A model was built to simulate human TSP performance and was used to investigate further the relationship between global information processing and local information processing. Our model was compared with the human data we collected and with other models of human TSP solving.     

Imagery in thinking and problem solving

The possible role of imagery in thinking and problem solving was examined by giving 20 subjects a practical construction test (Maier's hat rack problem). 5 men and 4 women solved the problem. Posttest questioning indicated two distinct types of imagery were used to solve the problem, imagination or memory in imagery. The solvers tended to use imagination in imagery and the nonsolvers memory in imagery. In Exp. 2, 40 subjects were specifically instructed to use one or another of these strategies. Those using imagination in imagery were more likely to solve the problem than those using memory in imagery. The conclusion was drawn that imagination in imagery favours and memory in imagery impedes the solving of this problem.     

Integration of information during problem solving due to a meaningful context of learning

Ninety-seven subjects memorized nine associations among six interlocking elements that were presented as links among nonsense letters, connections among spies with word code names (after Hayes, 1966), or airline flights among major US cities. On tests of problem solving and true-false judgments, the letters group and the words group performed nearly identically; however, relative to these two groups, the cities group performed worse or about the same on short recall problems and much better on longer problems requiring chunking of learned information. The conditions and effects of a meaningful learning context for problem solving were discussed.     

Hypothetical contractarianism and the disclosure requirement problem in informed consent

Two of the more deeply problematic issues surrounding the doctrine of informed consent are providing a justification for the practice of informed consent and providing an account of the nature and amount of information that must be disclosed in order for informed consent to take place. This paper is concerned with the latter problem, the problem of disclosure requirements, but it deals with this problem in a novel way; it approaches the problem by asking what fully informed and fully rational agents would agree to under certain hypothetical conditions. In general terms I juxtapose the hypothetical contractarianism found in Rawls' A Theory of Justice with that found in Gauthier's Morals By Agreement and ask what their respective hypothetical contractors would agree to with respect to choosing a particular standard of disclosure to govern the practice of informed consent. In more specific terms a contrast is made between what a Rawlsian agent behind a veil of ignorance would choose as compared to what, in Gauthier's terms, an ideal actor making an Archimedean choice would choose. The idea of an Archimedean point, and the subsequent choice made from that point, although technically identified by Rawls, originated with Archimedes of Syracuse.     

Mental representation of three-dimensional objects in visual problem solving and recognition

Subjects inspected sets of flat, separated orthographic projections of surfaces of potential three-dimensional objects. After solving problems based on these orthographic views, subjects discriminated between isometric views of the same objects and drawings of distractor structures. Recognition of the isometrics, which had never been shown during the problem solving phase of the experiment, was excellent. In addition, recognition of isometrics corresponding to problems that had been solved correctly when presented in orthographic form was significantly superior to recognition of isometrics based on problems solved incorrectly. In Experiment 2, conditions were included in which either orthographic or isometric views functioned as problem solving or recognition displays. Only in the case of orthographic problem solving followed by isometric recognition (Experiment 1) was the superiority of recognition for correctly-solved problems over incorrectly-solved problems obtained. The pattern of results suggests that viewers construct mental representations embodying structural information about integrated, three-dimensional objects when asked to reason about flat, disconnected projections.