Preschool children's mathematical knowledge: The effect of teacher "math talk."

This study examined the relation between the amount of mathematical input in the speech of preschool or day-care teachers and the growth of children's conventional mathematical knowledge over the school year. Three main findings emerged. First, there were marked individual differences in children's conventional mathematical knowledge by 4 years of age that were associated with socioeconomic status. Second, there were dramatic differences in the amount of math-related talk teachers provided. Third, and most important, the amount of teachers' math-related talk was significantly related to the growth of preschoolers' conventional mathematical knowledge over the school year but was unrelated to their math knowledge at the start of the school year. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Bayesian integration of spatial information.

Spatial judgments and actions are often based on multiple cues. The authors review a multitude of phenomena on the integration of spatial cues in diverse species to consider how nearly optimally animals combine the cues. Under the banner of Bayesian perception, cues are sometimes combined and weighted in a near optimal fashion. In other instances when cues are combined, how optimal the integration is might be unclear. Only 1 cue may be relied on, or cues may seem to compete with one another. The authors attempt to bring some order to the diversity by taking into account the subjective discrepancy in the dictates of multiple cues. When cues are too discrepant, it may be best to rely on 1 cue source. When cues are not too discrepant, it may be advantageous to combine cues. Such a dual principle provides an extended Bayesian framework for understanding the functional reasons for the integration of spatial cues. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Why do categories affect stimulus judgment?

The authors tested a model of category effects on stimulus judgment. The model holds that the goal of stimulus judgment is to achieve high accuracy. For this reason, people place inexactly represented stimuli in the context of prior information, captured in categories, combining inexact fine-grain stimulus values with prior (category) information. This process can be likened to a Bayesian statistical procedure designed to maximize the average accuracy of estimation. If people follow the proposed procedure to maximize accuracy, their estimates should be affected by the distribution of instances in a category. In the present experiments, participants reproduced one-dimensional stimuli. Different prior distributions were presented. The experiments verified that people's stimulus estimates are affected by variations in a prior distribution in such a manner as to increase the accuracy of their stimulus reproductions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"What counts in the development of young children's number knowledge?": Correction to Levine et al. (2010).

Reports an error in "What counts in the development of young children's number knowledge" by Susan C. Levine, Linda Whealton Suriyakham, Meredith L. Rowe, Janellen Huttenlocher and Elizabeth A. Gunderson (Developmental Psychology, 2010[Sep], Vol 46[5], 1309-1319). A coding error resulted in incorrect item-level data being reported on the point-to-x task (not the children‘s overall performance on this task) in Table 2 and in the section of the Results headed Point-to-X Task Performance (second column, p. 1314). In the first paragraph in the section, the correct average score for knowledge of cardinal meanings of the number words. In the second paragraph in the section, there is an example illustrating children’s greater performance on items involving a target and a distractor that were one digit apart. An additional adjustment in the second paragraph involves the finding that children performed better when at least one of two choice sets was a small number (1–3) than when both choice sets were greater than or equal to 4. More information for the corrections and the corrected table are given in the erratum. (The following abstract of the original article appeared in record 2010-17955-026.) Prior studies indicate that children vary widely in their mathematical knowledge by the time they enter preschool and that this variation predicts levels of achievement in elementary school. In a longitudinal study of a diverse sample of 44 preschool children, we examined the extent to which their understanding of the cardinal meanings of the number words (e.g., knowing that the word “four” refers to sets with 4 items) is predicted by the “number talk” they hear from their primary caregiver in the early home environment. Results from 5 visits showed substantial variation in parents' number talk to children between the ages of 14 and 30 months. Moreover, this variation predicted children's knowledge of the cardinal meanings of number words at 46 months, even when socioeconomic status and other measures of parent and child talk were controlled. These findings suggest that encouraging parents to talk about number with their toddlers, and providing them with effective ways to do so, may positively impact children's school achievement. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Children's early ability to solve perspective-taking problems.

Piaget and B. Inhelder (1967 [1948]) claimed that, until 9 or 10 yrs of age, children had great difficulty with perspective taking. J. Huttenlocher and C. C. Presson (1979) showed, however, that these problems were linked to conflict between actual and imagined frames of reference; asking what object occupied a specified location with respect to a hypothetical observer (item questions) led to much better performance. The present experiments extend these findings to younger children: 5-yr-olds (Exp 1); 4-yr-olds, for near and far locations but not left and right (Exp 2); 4-yr-olds for left–right questions (Exp 3); and 3-yr-olds (Exp 4). In addition, Exp 4 showed that memory was not the basis for answering. These data show clearly that preschool children can indicate locations relative to another position. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Bias in spatial location due to categorization: Comment on Tversky and Schiano.

B. Tversky and D. J. Schiano (1989) reported bias in reproducing the angle of a line in an "ell" frame. When no conceptual interpretation of the task was given, they argued that the bias was due to a perceptual process that produced an apparent tilt in the line (D. J. Schiano & B. Tversky, 1992). We propose that J. Huttenlocher, L. V. Hedges, and S. Duncan's (1991) model of category effects on estimates of stimulus values provides a better explanation of this bias. Two experiments are presented that examine these alternative views. The results show effects of the orientation of the frame and of an interference task on bias that are more consistent with J. Huttenlocher et al.'s model than with the perceptual explanation adopted by D. J. Schiano and B. Tversky. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of language intervention on syntactic skill levels in preschoolers.

Questions concerning the role of input in the growth of syntactic skills have generated substantial debate within psychology and linguistics. The authors address these questions by investigating the effects of experimentally manipulated input on children's skill with the passive voice. The study involved 72 four-year-olds who listened to stories containing either a high proportion of passive voice sentences or a high proportion of active voice sentences. Following 10 story sessions, children's production and comprehension of passives were assessed. Intervention type affected performance--children who heard stories with passive sentences produced more passive constructions (and with fewer mistakes) and showed higher comprehension scores than children who heard stories with active sentences. Theoretical implications of these results for the understanding of the nature of syntactic skills and practical implications for the development of preschool materials are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The varieties of speech to young children.

This article examines caregiver speech to young children. The authors obtained several measures of the speech used to children during early language development (14-30 months). For all measures, they found substantial variation across individuals and subgroups. Speech patterns vary with caregiver education, and the differences are maintained over time. While there are distinct levels of complexity for different caregivers, there is a common pattern of increase across age within the range that characterizes each educational group. Thus, caregiver speech exhibits both long-standing patterns of linguistic behavior and adjustment for the interlocutor. This information about the variability of speech by individual caregivers provides a framework for systematic study of the role of input in language acquisition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Numerical abstraction in infants: Another look.

This article examines an important finding from the literature on infant numerical competence. The finding, reported by P. Starkey, E. S. Spelke, and R. Gelman (1990), was that infants looked longer toward a visual display that was equal in number to an auditory set. In Experiment 1, when the procedures described by P. Starkey et al. were followed and duration was held constant across auditory sequences that varied in number, infants looked longer toward the display that was not numerically equivalent to the auditory set. In Experiment 2, when the rate and duration of the auditory sequences were varied randomly within infants, no significant preference for either the equivalent or nonequivalent visual display was shown. These results raise questions about P. Starkey et al.'s claims that infants can represent the numerosity of sets in different modalities and then perform one-one correspondence computations over them. (PsycINFO Database Record (c) 2010 APA, all rights reserved)