Counting on working memory in simple arithmetic when counting is used for problem solving

A concurrent-task methodology was used to investigate relations between the availability of aspects of working memory resources and both strategy selection and execution while simple addition equations (e.g., 4 + 3 = 8) were being verified. Consistent with prior research in which production trials have been used, undergraduates selected a variety of procedures other than retrieval. Availability of working memory resources did not generally affect strategy selection. Disrupting central executive and phonological aspects of memory affected strategy execution, but only when min counting was used to solve the problems. These and other features of the results suggest that availability of working memory resources does not contribute to individual differences in strategy selection and time to execute retrieval processes.     

Strategies for solving simple addition problems: A comparison of normal and subnormal children

Abstract.— Children in the third grade in a normal class and children poor in mathematics attending special classes solved all additions with the sum of the two positive addends smaller than 10. The cognitive processes leading to the solutions were described in relation to a process model predicting solution times. The general model included a counter with two operations, setting and incrementing by one unit. It is assumed that solutions are obtained either by direct retrieval from memory or by a reconstructive process. The first step in this process is finding the starting point for the counter which is the greater addend. When the problem has been defined and the starting point has been found the generation of the answers starts by the counter stepping the number of units denoted by the smaller addend. The results based mainly on latencies showed that children poor in mathematics, in addition to a slower processing rate, seemed to have difficulties in the choice of strategy for processing the information in a problem.     

Strategies in subtraction problem solving in children

The aim of this study was to investigate the strategies used by third graders in solving the 81 elementary subtractions that are the inverses of the one-digit additions with addends from 1 to 9 recently studied by Barrouillet and Lépine. Although the pattern of relationship between individual differences in working memory, on the one hand, and strategy choices and response times, on the other, was the same in both operations, subtraction and addition differed in two important ways. First, the strategy of direct retrieval was less frequent in subtraction than in addition and was even less frequent in subtraction solving than the recourse to the corresponding additive fact. Second, contrary to addition, the retrieval of subtractive answers is confined to some peculiar problems involving 1 as the subtrahend or the remainder. The implications of these findings for developmental theories of mental arithmetic are discussed.     

On retrieving analogues when solving problems

After criticism of the precision of previous experimental procedures for testing analogue retrieval, a new procedure that overcomes the proposed inadequacies is described. This procedure is then employed in two experiments that test aspects of the general hypothesis that base analogues that are semantically remote from a target problem (Duncker's radiation problem) are more difficult to retrieve than those that are semantically closer. Experiment 1 confirmed this hypothesis by finding that remote analogues are seldom retrieved relative to literal analogues. The results of Experiment 2 falsified the hypothesis that analogue retrieval is solely due to the recognition of an “identical element”. Finally, an ad hoc model of analogue retrieval is proposed based on Schank's dynamic memory theory, and its consistency with the evidence and more general implications are considered.     

Area-matching strategies used by young children

Across three studies, conditions were varied under which children aged 4–5 years matched the area of a rectangle with a given width (or height) to that of a square. In the first study, subjects observed the rectangle being changed in height from trial to trial and had access to their immediately preceding response. Under these conditions, rectangle width (the dimension under subject control) was a linear decreasing function of rectangle height. This function was interpreted as evidence for a hypothetical addition/subtraction strategy for maintaining equality in area between the comparison rectangle and the standard square. As a test of this hypothesis, in a second experiment the subjects were denied access to their immediately previous response, and in a third study they were also unable to observe the rectangle as it was altered by the experimenter between trials. The purpose of these changes was to remove the information necessary for readily implementing an addition/subtraction strategy. In both studies, area matches seemed to be based on a side-matching strategy, such that subjects matched one dimension of the rectangle to one side of the standard square. It was suggested that young children use different cues or strategies with different variants of the matching task because they do not possess a fixed, specific concept of area.     

Discovery misattribution: when solving is confused with remembering

This study explored the discovery misattribution hypothesis, which posits that the experience of solving an insight problem can be confused with recognition. In Experiment 1, solutions to successfully solved anagrams were more likely to be judged as old on a recognition test than were solutions to unsolved anagrams regardless of whether they had been studied. Experiment 2 demonstrated that anagram solving can increase the proportion of "old" judgments relative to words presented outright. Experiment 3 revealed that under certain conditions, solving anagrams influences the proportion of "old" judgments to unrelated items immediately following the solved item. In Experiment 4, the effect of solving was reduced by the introduction of a delay between solving the anagrams and the recognition judgments. Finally, Experiments 5 and 6 demonstrated that anagram solving leads to an illusion of recollection.     

Some attributes of adjectives used by young children

Analysis of 24 spontaneous speech samples from children at 24 and 30 months revealed a correlated progression in the form, function and meaning of modifiers used with increased language development. Predicate adjectives were used to comment on transitory states of objects and predominated in the early speech samples. Attributive adjectives were used to subdivide classes or to specify among particular instances within classes on the basis of physical characteristics such as size, by use of a conventional type name, or by use of a possessive. Attributives predominated in the later speech samples. Differential use of a particular form appears to be a function of its cognitive and communicational usefulness rather than its syntactic derivation.     

Spatial cognition: gathering strategies used by preschool children

How preschool children retrieve hidden objects was examined in two cross-sectional studies. The first was a simple task in which 1- and 3-year-olds saw two treats hidden in their living room. The newly walking infants generally sought the closer treat first, providing evidence for a least-distance spatial strategy. However, this strategy was affected by a tendency to approach the hiding place most recently baited. Three-year-old children used a least-distance strategy regardless of the order of hidings. In Experiment 2, 3- and 5-year-olds saw 12 puzzle pieces hidden in various containers equally spaced within a naturally furnished children's laboratory. Factors in addition to age were the distinctiveness of the containers and a requirement to return to the center of the array after each retrieval. Overall, children of both age groups were quite successful at this task, retrieving 11 of the pieces. However, 3-year-olds were less efficient, retrieving fewer pieces and requiring more searches. Detailed analyses of errors and patterns of choices indicated differential processes in achieving their performance. Three-year-old children showed the use of memories for events, discrimination of classes of hiding places, and efficient spatial biases. Five-year-old children were more likely to exhibit these processes concurrently.     

Selectors' Decision Strategies when Assessing Immigrant Job Applicants

Immigrant job applicants are often not fluent in the majority language. This raises the question whether selectors adjust their decision strategy when selecting immigrants. In two field studies (N = 1,949 and N = 156), we examined the decision strategies of professional selectors. Selectors used differential strategies, giving less weight to the test scores and impression scores of immigrants. Dutch language proficiency served as a moderator variable; test scores were considered less important in the employment recommendation especially for immigrants with low language skills. Yet professional selectors also used similar strategies for different groups; the same test scores led to the same recommendations, regardless of ethnicity. In sum, personnel selectors adjusted their decision strategy for immigrants, but this did not lead to immigrants receiving higher recommendations than majority applicants with similar test scores.     

Strategies in landmark use by orangutans and human children

Landmark use has been demonstrated in a variety of organisms, yet the manner in which landmarks are encoded and subsequently used appears to vary between and sometimes within species, even when faced with identical landmark arrays. In the present experiments, orangutans and human children were shown a square array of identical landmarks and were trained to locate a hidden goal in the centre of the array. In Experiments 1 and 2, the search space appeared to be discrete, with white gridlines dividing up the space, and in Experiments 3a and 3b, the search space was uniformly coloured, making it appear continuous. In all experiments, following training, subjects were given a single expansion test, to determine their landmark strategy use, based on peak search activity. The orangutans appeared to use absolute directional vectors from individual landmarks, with peak search activities on the inner corners of the square array, and they used this strategy persistently. In contrast, human children showed two landmark-based strategies, absolute directional vectors and a relational or “middle” strategy, with the majority of children starting their search in the middle region. Although some children, especially young children, persistently used one strategy like the orangutans, many changed strategies when the original one failed to yield the hidden goal.     

Strategies in processing new versus old information by children

This study investigated how children linguistically encode new versus old information as a function of age on a Receptive and an Expressive Task. Kindergarteners and third-graders were presented with picture pairs. Members of each picture pair were identical except for one obvious detail, the new information. While there was little difference between the two age groups on the Receptive Task, statistically significant differences were found on the Expressive Task. Results were discussed in terms of children's cognitive/perceptual strategies in encoding new versus old information.     

Inside Criminal Minds: Offenders' Strategies when Lying

This study aimed at extending the deception literature by examining lie‐telling strategies given by persons with criminal experience. In interviews taking place in prisons, offenders (n = 35) provided lie‐telling strategies in a free narrative style. In an inductive content analysis, we coded both all strategies provided as well as one principal strategy for each participant. In total, 13 strategies were identified, which were grouped into three broader category groups: general verbal, general nonverbal, and specific interview strategies. The most often stated strategies were Close to truth, Eye contact, and No strategy. The most often stated principal strategies were Close to truth, Not giving away information, and No strategy. Some participants provided strategies, such as not giving away information at all in interviews/interrogations, which showed a sophisticated understanding of the police interview situation and the task of the police and prosecutor. Overall, the participants showed great diversity in preferred lie‐telling strategy. The results are partly in line with previous research from student samples and provide new insights into the criminally experienced individuals' lie‐telling strategies. The results are discussed with regard to impression and information management and police interrogation practice. Copyright © 2011 John Wiley & Sons, Ltd.     

Automatic and directed search processes in solving simple semantic-memory problems

The cognitive processes involved in simple semantic-memory problems were investigated in four experiments. On each trial of Experiments 1 and 2, two stimulus words were presented, with the instructions to find a third word (i.e., the solution) that, when coupled with each of the stimuli, would yield two word pairs used in everyday language (e.g., surprise and birthday, for which the solution is party). The results of the two experiments indicated that informing the subject whether the solution constituted the first or the second element in the word pairs facilitated both likelihood and speed of solution attainment. In addition, solution attainment was relatively high for items based on frequently used word pairs (Experiment 1) and for items in which the stimuli appear, in everyday language, in a small number of word pairs (Experiment 2). In Experiment 3, the subjects were required to produce word pairs containing one of the two stimulus words from the items used in Experiment 2. Solution production was facilitated by rehearsing the second stimulus word of the specific item. The conclusion, supported by a post hoc analysis of the results of Experiments 2 and 3 (Experiment 4), was that indirect priming from one stimulus word may facilitate solution production from a searched word. These results are interpreted in terms of automatic and controlled processes, and their relevance to two different models for retrieval from semantic memory is discussed.     

Strategies used for unconstrained direction change during walking

Full functional mobility requires adaptations, such as turning, to the basic straight locomotor pattern. The aim was to assess the mechanics of completing a complex turning manoeuvre. A full 3-dimensional kinematic and kinetic analysis of the ipsilateral limb was carried out during both straight gait and unconstrained turning through 90 degrees. 10 healthy university students participated. Analysis indicated that two distinctive substrategies of the spin turn-ipsilateral pivot and ipsilateral crossover-were employed. The ipsilateral pivot was the more dynamic turn and required two additional power phases at the ankle and hip to facilitate the pivot phase. The ipsilateral crossover uses a fall into the new direction. The spin turn is a more complex action than previously indicated.     

Social problem solving among popular and unpopular children

The present study investigated two issues related to children's social status and problem solving: the content of problem-solving measures and judgments of the quality of responses to social problems. Three types of social problem situations were studied: peer entry/initiation, maintaining social interaction, and management of conflict. The quality of children's strategies for solving these problems was rated on two dimensions: effectiveness and social competence. Liked-most children obtained significantly more effective and socially competent ratings than liked-least children for only one of the social problem situations-management of conflict. Significant differences between liked-most and liked-least children were also found between the quality of their best effective and best socially competent solution and their worst socially competent solutions. Results are discussed in terms of the psychometric adequacy of social problem-solving measures and the resultant problems in interpretation.This article is based on a doctoral dissertation submitted by the first author to the Graduate School, University of North Carolina-Chapel Hill. The first author appreciates the assistance of her dissertation committee: John Brantley, Donald Bailey, Barbara Goldman, and Rune Simeonsson. We also thank Carolyn Jackson, Alex Epanchin, Joanne Edelman, and the kindergarten teachers and assistants in Durham, North Carolina, for their help with data collection, Michael Fimian for his statistical help, Joanne Gartenmayer for her help with editing, and Karen Thigpen for her help with typing.