Biomedical subjects

R S Siegler

Publications and source records attributed to R S Siegler.

At least 19 recordsLinked to original sources

PubMed2001

Seeds aren't anchors.

Exposure to a few task-relevant numerical facts (seed facts) often improves subsequent numerical estimates. We performed two experiments to investigate the mechanism that produces these seeding effects. In Experiment 1, participants estimated national populations; in Experiment 2, they estimated between-city distances. In both, items were selected so that the actual value of the seed facts (SA) was, on average, below participants' initial estimates for those items (S1) and above the initial estimates for the transfer items (T1). Given this configuration, the anchoring position predicts that the postseeding transfer estimates should be greater than the preseeding transfer estimates (T2 > T1), whereas the feedback/induction position predicts the opposite (T2 < T1). In both experiments, the latter pattern of results emerged, supporting the conclusion that seeds aren't anchors.

Adult↗

PubMed2000

Across the great divide: bridging the gap between understanding of toddlers' and older children's thinking.

Research on very young children's cognitive development differs greatly from research on cognitive development in older children. The differences include the questions that are asked, the methods that are used to address them, the measures that are employed to provide relevant evidence, and the level of detail at which children's knowledge is represented. The research approaches are so different that they create an impression that infants' and toddlers' thinking differs qualitatively from that of preschoolers and older children. This impression, however, may reflect differences in research approaches rather than differences in children's thinking. In the present study, we attempted to bridge this gap by applying to toddlers a type of process analysis that has proved fruitful in studies of older children. Overlapping waves theory, trial-by-trial strategy assessments, and microgenetic methods were used to analyze 1.5- and 2.5-year-olds' problem solving and learning. The results demonstrated that changes in toddlers' strategies could be assessed reliably on a trial-by-trial basis, that the changes followed the basic form predicted by the overlapping waves model, and that analyses of toddlers' strategies could tell us a great deal about both qualitative and quantitative aspects of their learning. A componential analysis of learning that previously had been applied to older children also proved useful for understanding toddlers' learning. The analysis specified that cognitive change frequently involves five components: acquisition of new strategies; strengthening of the strategies in their original context; improved mapping of strategies onto novel problems; increasingly refined choices among variants of the strategies; and increasingly skillful execution of the strategies. Independent measures of these components indicated that strategic development in toddlers involves improvements in all five components. Analyses of individual differences in learning showed that the effects of distal variables, such as age and sex, could be partially explained in terms of their influence on mastery of the components, but that the distal variables exercised additional direct effects as well. The process of learning in toddlers closely resembled that of older children in other ways as well. Like older children, toddlers use multiple strategies over the course of learning; their choices among strategies are quite adaptive from early on; their choices become progressively more adaptive as they gain experience with the task; they switch strategies not only from trial to trial but within a single trial; their transfer of learning from one problem to the next is primarily influenced by structural relations between problems but also is influenced by superficial features; they show utilization deficiencies early in learning that they gradually overcome; and they show individual differences in learning that fall into a few qualitatively distinct categories. Perhaps most striking, the 1.5- and 2.5-year-olds emerged as active learners, who continued to work out the lessons of previous instruction in the absence of further instruction. That is, they integrated the lessons of their own problem-solving efforts with the previous instruction in ways that magnified the initial effects of the instruction. Overall, the findings indicated that the gap can be bridged; that theories, methods, measures, and representations of knowledge typically used with older children can improve our understanding of toddlers' problem solving and learning as well.

Child Behavior↗

PubMed1998

Developmental differences in rule learning: a microgenetic analysis.

Trial-by-trial strategy assessments and a microgenetic design were used to examine 4- and 5-year-olds' learning of rules for solving balance scale problems. The design allowed us to examine simultaneously the contribution to rule learning of distal variables (qualities and knowledge with which children enter the learning situation) and proximal variables (processes that they execute during learning). Developmental differences in learning arose through two distal variables that were correlated with age--initial rule use and initial encoding-helping older children to execute several proximal processes--noticing the potential explanatory role of a key variable, formulating a more advanced rule, and generalizing and maintaining the rule. Joint consideration of distal and proximal influences seems likely to be generally useful for understanding learning and development.

Age Factors↗

PubMed1998

Conscious and unconscious strategy discoveries: a microgenetic analysis.

We examined second graders' strategy discoveries on a task that could be solved either by arithmetic computation or by a simple insight. Strategy use was assessed on each trial through both an implicit measure and an explicit one. The results provided unambiguous evidence that strategies can be discovered without conscious awareness. Almost 90% of children showed the insight at an implicit, unreportable level before they showed it at an explicit, reportable one. When children received the relevant problems on each trial, 80% reported the insight within 5 trials of when their solution times indicated that they first generated it. Implications for understanding the relation between unconscious and conscious discoveries and for the role of competing activations in strategy discovery are discussed.

Awareness↗

PubMed1998

"Hey, would you like a nice cold cup of lemonade on this hot day?": children's understanding of economic causation.

Three experiments were performed to examine development of understanding of functional relations in economics by children between ages 4 and 10 years. Results of Experiment 1 indicated that preschoolers understood the effects of demand, and 2nd graders also understood the effects of supply, but even 4th graders often failed to demonstrate understanding of the effects of motivation and morality. In Experiment 2, 4th but not 2nd graders proved able to explain how motivation and morality might influence sales when told that these variables had an effect. In Experiment 3, 2nd and 4th graders' evaluations of the plausibility of other children's explanations of effects of motivation and morality showed evidence of understanding, though those of kindergartners did not. The data supported the 3 hypotheses that motivated the experiments: (a) direct links between causes and effects are understood before indirect ones, (b) positive correlations between causes and effects are understood before negative ones, and (c) variables that produce effects are understood before ones that do not.

Child↗

PubMed1997

A comparison of the geometric reasoning of students attending Israeli ultraorthodox and mainstream schools.

Effects of schooling on a geometric misconception were examined by comparing the performance of Israeli students attending ultraorthodox schools with that of peers attending mainstream schools. These groups were of special interest because both value education highly and send essentially all children to school, but I group receives extensive instruction in mathematics and science and the other receives almost none. Despite the ultraorthodox 12- to 14-year-olds' having received no instruction in geometry, they more often solved the geometric misconception problems than did mainstream peers who had received extensive instruction in the subject. Mainstream 16- to 18-year-olds did somewhat better on the misconception task than did orthodox age peers, but even there, the advantage of the mainstream students was limited to those exposed to the most advanced mathematics curriculum. How mainstream and orthodox schooling may have contributed to these findings is discussed.

Achievement↗

PubMed1997

Older and younger adults' strategy choices in multiplication: testing predictions of ASCM using the choice/no-choice method.

The choice/no-choice method provides a means of obtaining unbiased estimates of the performance characteristics of strategies. The three experiments in the study illustrate the method's usefulness for testing predictions of alternative models of strategy choice. The experiments focused on 20- and 70-year-olds' choices among mental calculation, use of a calculator, and use of pencil and paper as strategies for solving multidigit multiplication problems. As predicted by the Adaptive Strategy Choice Model (ASCM), (a) differences in the speed and accuracy yielded by the strategies were the strongest predictors of the frequency with which each strategy was chosen on a given problem; (b) features of problems exerted an additional independent influence; and (c) having a choice resulted in better performance than not having one. These results held true for both older and younger adults. Potential extensions of the choice/no-choice method and of ASCM are discussed.

Adolescent↗

PubMed1997

Rethinking infant knowledge: toward an adaptive process account of successes and failures in object permanence tasks.

Infants seem sensitive to hidden objects in habituation tasks at 3.5 months but fail to retrieve hidden objects until 8 months. The authors first consider principle-based accounts of these successes and failures, in which early successes imply knowledge of principles and failures are attributed to ancillary deficits. One account is that infants younger than 8 months have the object permanence principle but lack means-ends abilities. To test this, 7-month-olds were trained on means-ends behaviors and were tested on retrieval of visible and occluded toys. Means-ends demands were the same, yet infants made more toy-guided retrievals in the visible case. The authors offer an adaptive process account in which knowledge is graded and embedded in specific behavioral processes. Simulation models that learn gradually to represent occluded objects show how this approach can account for success and failure in object permanence tasks without assuming principles and ancillary deficits.

Child Development↗

PubMed1996

Development of arithmetical competencies in Chinese and American children: influence of age, language, and schooling.

The arithmetical competencies of more than 200 Chinese or American kindergarten, first-, second-, or third-grade children were assessed toward the beginning and toward the end of the U.S. school year. All children were administered a paper-and-pencil test of addition skills, a digit span measure, and an addition strategy assessment. The addition strategy assessment provided information on the types of strategies the children used to solve simple addition problems as well as information on the speed and accuracy of their strategy use. Information on the number of math instruction periods across times of measurement was also obtained for each of the first-, second-, and third-grade children. The pattern of arithmetical development across the academic year and across the Chinese and American children suggests that a mix of cultural and maturational factors influence the emergence of early arithmetical competencies and that the Chinese advantage in early mathematical development is related to a combination of language- and school-related factors.

Achievement↗

PubMed1995

How does change occur: a microgenetic study of number conservation.

Microgenetic methods can illuminate the path, rate, breadth, variability, and sources of change. The present study illustrates the types of information the method can yield in the context of number conservation. Five-year-olds whose pretest performance showed that they had not mastered number conservation were presented four training sessions. Some were just given feedback on their number conservation performance; others were given feedback and asked to explain the reasoning that led to the experimenter's judgment. Being asked to explain the experimenter's reasoning produced considerably more learning than either of the other two procedures. The learning involved two distinct realizations: that relative length did not predict which row had the greater number of objects and that the type of quantitatively relevant transformation did. Individual children generated multiple types of reasoning about conservation, both on the pretest and throughout the training procedure; understanding the importance of the type of transformation did not lead to immediate rejection of less advanced forms of reasoning, even for a single problem presented several times during the experiment. This variability was positively associated with learning; children who showed greater variability of reasoning on the pretest, both within and across trials, learned more. Educational and theoretical implications of children's efforts to understand other people's reasoning were discussed.

Child↗

PubMed1995

Four aspects of strategic change: contributions to children's learning of multiplication.

This study reports a longitudinal investigation of French 2nd graders' acquisition of single-digit multiplication skill. Speed, accuracy, and strategy use were assessed 3 times within the year when children learned multiplication. The data showed that improvements in speed and accuracy that generally accompany learning can reflect at least 4 types of specific strategic changes: introduction of new strategies, increasing use of the most efficient existing strategies, more efficient execution of each strategy, and more adaptive choices among strategies. The data also showed substantial continuities in learning: At all 3 points of measurement, children used multiple strategies, used retrieval most often on the same classes of problems, and used repeated addition on the most difficult problems. Stable individual differences were also apparent. The findings supported a number of predictions of Siegler and Shipley's (1995) adaptive strategy choice model. Implications for understanding learning, arithmetic, and strategy choice processes are discussed.

Child↗

PubMed1994

Constraints on learning in nonprivileged domains.

Constraints on learning, rather than being unique to evolutionarily privileged domains, may operate in nonprivileged domains as well. Understanding of the goals that strategies must meet seems to play an especially important role in these domains in constraining the strategies that are generated and in allowing children to evaluate strategies even before they use them. The present experiments showed that children can use their conceptual understanding to accurately evaluate strategies that they not only do not yet use but that are more conceptually advanced than the strategies they do use. In Experiment 1, 5-year-olds who did not yet use the min strategy for adding numbers judged it to be smarter than an equally novel illegitimate strategy, and to be just as smart as their typical strategy of counting from one. In Experiment 2, 9-year-olds who did not yet use the forking strategy to play tic-tac-toe judged it to be even smarter than their own win/block approach. The results demonstrated a large number of commonalities between the functioning of constraints in privileged and nonprivileged domains, as well as suggesting some possible differences.

Child↗

PubMed1994

The relationship between age and major league baseball performance: implications for development.

Lifetime performance data of 388 baseball players active in 1965 were analyzed to determine the age of peak performance for skills required to play baseball, to derive age-performance curves for athletic productivity, and to assess the magnitude of individual differences among elite and less able players. Cross-sectional and longitudinal analyses show that athletic performance on key indicators rises relatively quickly from age 19 to a peak age of 27 and then declines. The primary difference between elite and less able players is that performance of the elite players remains high for a longer period of time and decays more gradually. The performance of the most elite players is superior to that of less able players even at very early ages. These results parallel findings reported for other achievement domains and can be explained in terms of basic developmental processes involving the interaction of experience, physiological capacity, and motivation.

Adolescent↗

PubMed1993

Metrics and mappings: a framework for understanding real-world quantitative estimation.

Estimation is influenced by a variety of processes: application of heuristics, domain-specific reasoning, and intuitive statistical induction, among them. In this article, we propose the metrics and mapping framework to account for how these processes are integrated to generate estimates. This framework identifies 2 types of information as critical: knowledge of distributional properties (metric knowledge) and knowledge of relative status of individual entities within the distribution (mapping knowledge). Heuristics and domain-specific knowledge are both viewed as cues that contribute to mapping knowledge; intuitive statistical induction is viewed as providing cues to metric properties. Results of 4 experiments illustrate the framework's usefulness for integrating these types of information and for predicting when people emphasize heuristics and when they emphasize domain-specific knowledge.

Adolescent↗

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↗