Sex-related differences on objective tests among undergraduates

Objective tests, such as multiple-choice and relationship analysis questions, are often used in mathematics to assess certain ranges of skills and abilities. This article examines the performance of men and women students in mathematics at university level and shows that there are significant differences between the sexes.     

Mirror-image stimulation and short separations in stumptail monkeys

Two experiments examined the responses of infant stumptail macaques (Macaco arctoides) to mirror-image stimulation (MIS) during short social separations. Overall, infants living in pairs showed agitation when separated from their partners, but were calmer when the partner, an unfamiliar peer, or their own mirror image was visible. MIS elicited more facial expressions than the familiar peer, and more affiliative contact than an unfamiliar peer. In contrast, infants reared in a group were not calmed during separations either by an unfamiliar peer or by MIS, and they exhibited some negative reactions to the mirror. Social responsiveness to MIS varies with the social background of the subjects.     

Postpartum depression, marital dysfunction, and infant outcome: a longitudinal study

This longitudinal study explores the relationship of postpartum depression (PPD) and marital dysfunction on infant outcomes from birth to 2 1/2 years of age among middle-class, postpartum women. Participants were recruited during the prenatal period. Twelve mothers completed the study throughout a 2 1/2-year period. Questionnaires, semistructured interviews, and observations were used to collect data. Content analysis of the interviews (Morse & Field, 1995) was conducted and thematic patterns were identified. Clinical PPD and marital dysfunction (defined as little or no support or closeness, or verbal, emotional or physical abuse) characterized nearly one in three mothers. Four themes describing the women's postpartum progression were identified: stress, isolation, resentment, and eventual adjustment by creating a new normal. No major developmental delays or behavioral problems were found among the infants. Eight of the 12 mothers who were initially identified as breastfeeding nursed their infants for 6-18 months. Regardless of financial and educational advantages, mothers in the study experienced depression and marital dysfunction. These findings support other studies that confirm the lack of association of PPD with social class or marital status. Childbirth educators and other health care professionals are encouraged to continue providing expectant families with anticipatory education and community resources in order to increase awareness of mental health and marital risks during the postpartum transition.     

The effects of preferred representations on some tasks using solid geometrical figures

Privileged (typical, basic-level) representations are cognitive representations in which figurative features play a significant part. We specifically consider studies on the conventional point of view in object perception (Palmer, Rosch, & Chase, 1981). We propose an analysis of solid geometrical problems in the field of typicality theory and more generally in the theoretical field of mental models. Applied to this geometrical domain, the analysis suggests that individual cognitive representations — corresponding with different points of view from which a figure can be seen — are more or less representative examples of the category, that is to say they correspond more or less with the mental model built by the subject in this domain. Task 1 emphasizes the most representative point of view for four solid geometrical figures chosen by the experimenter. Then, we analyse two tasks on each figure from both the typical and non typical points of view. Errors occur most frequently when the geometrical figure is seen from its non typical viewpoints. Particular attention should be paid to this factor in analysing errors made by subjects.     

Teaching the design and interpretation of graphs through computer-aided graphical data analysis

Graphs are one of the primary means of exploration and communication in the practice of science, but students in science laboratories are customarily taught only the low-level mechanics of constructing a single kind of graph when given a table of information. The use of a microcomputer can relieve the drudgery of plotting, allowing students to pursue higher-level issues in the design and interpretation of graphs through repeated “thought experiments.” We introduced computer-assisted graphical data analysis to inner-city high school students with weak math and science backgrounds, emphasizing the dynamic manipulation of various kinds of graphs to answer specific questions. Drawing on extensive recordings and classroom observations, we describe examples of the performance of these students on open-ended problem-solving tasks in which graphs can be used to arrive at meaningful answers to applied data analysis problems.     

Winning the battle and losing the war: Examining the relation between grade retention and dropping out of high school

The aim of this investigation is to provide a comprehensive review of dropout research that examines grade retention within both associative and predictive models. A systematic review of seventeen studies examining dropping out of high school prior to graduation demonstrates that grade retention is one of the most powerful predictors of dropout status. The discussion addresses the discrepancies among the perspectives of many educational professionals regarding the effectiveness of grade retention and deleterious long‐term correlates. The transactional model of development is presented, which emphasizes developmental trajectories over time, in order to facilitate the interpretation of the association between grade retention and school withdrawal. Educational professionals, teachers, researchers, parents, and policymakers considering the efficacy of grade retention are encouraged to consider the implications of these findings. © 2002 Wiley Periodicals, Inc.     

Summation of undetected excitation following extinction of the CER

The effects of compounding two conditioned stimuli (CSs), each of which had been extinguished to varying degrees in different groups of rats given identical acquisition training, was examined within the conditioned emotional response paradigm. Greater suppression to the compound than to the individual CSs was observed following 6, 12, 48, 72, and 96 stimulus extinction trials, although after only 12 extinction trials suppression to the individual stimuli was no longer observed. The amount of compound suppression decreased progressively as the number of extinction trials increased until, after 120 extinction trials on each stimulus, the compound no longer elicited observable suppression. Control group data indicated that the observed summation effect could not be attributed to disinhibition. The possible role of the summation of undetected excitation in studies examining configurai conditioning, avoidance conditioning and reinstatement is discussed briefly.