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R S Siegler

Publications and source records attributed to R S Siegler.

9 recordsLinked to original sources
PubMed1992

The role of availability in the estimation of national populations.

In two parallel experiments, conducted 17 months apart, we examined the relations among population estimates, availability, and media coverage of the 100 countries with populations of 4 million or more. The results were consistent with the main hypothesis, that availability influences population estimates. Specifically, we found that (1) rated knowledge of each country (our measure of availability) was strongly correlated with estimated population for that country; (2) rated knowledge was more strongly correlated with estimated population than were other plausible predictors, such as land area; (3) a strong partial correlation between rated knowledge and estimated population remained even after true population and true land area were partialed out; and (4) longitudinal changes in rated knowledge predicted longitudinal changes in estimated population. Also as hypothesized, media coverage was positively related to availability and to population estimates. Further, we found that population estimates, rated knowledge, and amount of media coverage that each country received were very stable over the year-and-a-half period. These results led us to consider when availability is most likely to be relied upon heavily in quantitative estimation and how it may be integrated with other knowledge to derive quantitative estimates.

Adult↗
PubMed1991

The microgenetic method. A direct means for studying cognitive development.

Progress in understanding cognitive developmental change mechanisms requires methods that yield detailed data about particular changes. The microgenetic method is an approach that can yield such data. It involves (a) observations of individual children throughout the period of the change, (b) a high density of observations relative to the rate of change within that period, and (c) intensive trial-by-trial analyses intended to infer the processes that gave rise to the change. This approach can illuminate both qualitative and quantitative aspects of change, indicate the conditions under which changes occur, and yield otherwise unobtainable information about short-lived transition strategies. The cost in time and effort of such studies is often high, but the value of the information about change can more than justify the cost.

Achievement↗
PubMed1991

Subjective organization of U.S. presidents.

College students appear to subjectively organize U.S. presidents into three groups and to use this organization to help them learn new information. Results of a paired comparison task in Experiment 1 suggested that subjects organized the presidents into Founding Fathers (Washington through John Quincy Adams), post-World War II presidents (Truman through Reagan), and noncontemporary presidents (Jackson through Franklin Roosevelt). This hypothesized organization was tested in Experiment 2 by presenting subjects with several lists with alternative organizations of the presidents. Difficulty of learning classifications of particular presidents within each list was predicted on the basis of the relation between that president's classification in the list and in the hypothesized preexisting organization. Instances where the preexisting and new classifications were consistent both for the particular president and for all other members of the group were easiest to learn. Instances where the particular president's classification was consistent but where some other presidents in the group were classified differently were of intermediate difficulty. Instances where neither the individual president's classification nor that of the entire group were consistent were most difficult. The results provided converging evidence for the hypothesized subjective organization of the presidents and also demonstrated the usefulness of a method that may be applicable to testing subjective organizations in a wide variety of other areas.

Adolescent↗
PubMed1990

Misconceptions about motion: development and training effects.

2 experiments were performed to examine whether children and adults possess a single-object/single-motion intuition. This intuition involves the view that because all parts of a rigid object move together, they all must move at the same speed. We found that third graders, sixth graders, ninth graders, and adults all responded in accord with this intuition. On problems where the intuition led to errors, a large majority of subjects of all ages answered incorrectly. On problems where it led to successful performance, subjects answered more accurately than on problems where the intuition was not applicable. In addition, the specific errors were those that the intuition yielded, and the intuition fit individual patterns of performance. The intuition not only influenced speed judgments but also judgments of distance traveled. Experiment 2 demonstrated that making sixth graders aware of the intuition and providing them kinesthetic experience that contradicted it produced significant improvements in the children's understanding. Implications for how scientific misconceptions in general can be overcome were discussed.

Acceleration↗
PubMed1989

How children choose among serial recall strategies.

A theoretical and methodological approach originally developed to investigate preschoolers' arithmetic strategies was extended to the study of 5-8-year-olds' serial recall strategies. Immediately retrospective verbal reports, together with observation of overt behavior, indicated a number of parallels between strategy choices in the 2 areas. In serial recall, as in arithmetic, most children used multiple approaches. Even among the youngest children, the majority sometimes used the most effective strategy, repeated rehearsal. Changes in strategy choices were adaptive in the sense of children rehearsing more often when not rehearsing on the previous trial had led to incorrect recall. Developmental changes occurred in how often children rehearsed, in how accurately they executed each strategy, and in the type of rehearsal that they used most frequently. Only small changes were apparent, however, in whether the 5-8-year-olds rehearsed at all.

Attention↗
PubMed1988

Strategy choice procedures and the development of multiplication skill.

Many intelligent strategy choices may be accomplished through relatively low-level cognitive processes. This article describes a detailed model of how such "mindless" processes might lead to intelligent choices of strategies in one common situation: that in which people need to choose between stating a retrieved answer and using a backup strategy. Several experiments testing the model's applicability to children's single-digit multiplication are reported. These include tests of predictions about when different strategies are used and how early experience shapes later performance. Then, the sufficiency of the model to generate both performance at any one time and changes in performance over time is tested through the medium of a running computer simulation of children's multiplication. The simulation acquires a considerable amount of multiplication knowledge, and its learning and performance parallel those of children in a number of ways. Finally, several implications of the model for understanding cognitive self-regulation and cognitive development are discussed.

Association Learning↗
PubMed1988

Individual differences in strategy choices: good students, not-so-good students, and perfectionists.

Consistent individual differences were found in first graders' strategy choices in addition, subtraction, and reading (word identification). Differences were present along 2 dimensions: knowledge of problems and stringency of thresholds for stating retrieved answers. Cluster analyses indicated that children could be classified into 3 groups: good students, not-so-good students, and perfectionists. Perfectionists were children who had good knowledge of problems and set very high thresholds for stating retrieved answers, good students also had good knowledge of problems but set lower thresholds, and not-so-good students had less good knowledge of problems and set low thresholds. Differences among the 3 groups were evident on measures not included in the cluster analysis as well as measures that were. Further, the groups differed in standardized achievement test performance 4 months after the experiment in ways consistent with the experimental analysis. The pattern of individual differences was similar in 2 experiments with different samples of children and problems and different methods for assessing strategy use. The results illustrated how detailed cognitive models can contribute to understanding of individual differences.

Achievement↗