Janet Shibley Hyde

The Gender Similarities Hypothesis.

The differences model, which argues that males and females are vastly different psychologically, dominates the popular media. Here, the author advances a very different view, the gender similarities hypothesis, which holds that males and females are similar on most, but not all, psychological variables. Results from a review of 46 meta-analyses support the gender similarities hypothesis. Gender differences can vary substantially in magnitude at different ages and depend on the context in which measurement occurs. Overinflated claims of gender differences carry substantial costs in areas such as the workplace and relationships.

Gender differences in mathematics performance: a meta-analysis.

Reviewers have consistently concluded that males perform better on mathematics tests than females do. To make a refined assessment of the magnitude of gender differences in mathematics performance, we performed a meta-analysis of 100 studies. They yielded 254 independent effect sizes, representing the testing of 3,175,188 Ss. Averaged over all effect sizes based on samples of the general population, d was -0.05, indicating that females outperformed males by only a negligible amount. For computation, d was -0.14 (the negative value indicating superior performance by females). For understanding of mathematical concepts, d was -0.03; for complex problem solving, d was 0.08. An examination of age trends indicated that girls showed a slight superiority in computation in elementary school and middle school. There were no gender differences in problem solving in elementary or middle school; differences favoring men emerged in high school (d = 0.29) and in college (d = 0.32). Gender differences were smallest and actually favored females in samples of the general population, grew larger with increasingly selective samples, and were largest for highly selected samples and samples of highly precocious persons. The magnitude of the gender difference has declined over the years; for studies published in 1973 or earlier d was 0.31, whereas it was 0.14 for studies published in 1974 or later. We conclude that gender differences in mathematics performance are small. Nonetheless, the lower performance of women in problem solving that is evident in high school requires attention.

The Role of the Media in Body Image Concerns Among Women: A Meta-Analysis of Experimental and Correlational Studies

Research suggests that exposure to mass media depicting the thin-ideal body may be linked to body image disturbance in women. This meta-analysis examined experimental and correlational studies testing the links between media exposure to womens body dissatisfaction, internalization of the thin ideal, and eating behaviors and beliefs with a sample of 77 studies that yielded 141 effect sizes. The mean effect sizes were small to moderate (ds = -.28, -.39, and -.30, respectively). Effects for some outcome variables were moderated by publication year and study design. The findings support the notion that exposure to media images depicting the thin-ideal body is related to body image concerns for women.

The Objectified Body Consciousness Scale Development and Validation

Using feminist theory about the social construction of the female body, a scale was developed and validated to measure objectified body consciousness (OBC) in young women (N = 502) and middle-aged women (N = 151). Scales used were (a) surveillance (viewing the body as an outside observer), (b) body shame (feeling shame when the body does not conform), and (c) appearance control beliefs. The three scales were demonstrated to be distinct dimensions with acceptable reliabilities. Surveillance and body shame correlated negatively with body esteem. Control beliefs correlated positively with body esteem in young women and were related to frequency of restricted eating in all samples. All three scales were positively related to disordered eating. The relationship of OBC to womens body experience is discussed.

Gender differences in self-esteem: a meta-analysis.

Two analyses were conducted to examine gender differences in global self-esteem. In analysis I, a computerized literature search yielded 216 effect sizes, representing the testing of 97,121 respondents. The overall effect size was 0.21, a small difference favoring males. A significant quadratic effect of age indicated that the largest effect emerged in late adolescence (d = 0.33). In Analysis II, gender differences were examined using 3 large, nationally representative data sets from the National Center for Education Statistics (NCES). All of the NCES effect sizes, which collectively summarize the responses of approximately 48,000 young Americans, indicated higher male self-esteem (ds ranged from 0.04 to 0.24). Taken together, the 2 analyses provide evidence that males score higher on standard measures of global self-esteem than females, but the difference is small. Potential reasons for the small yet consistent effect size are discussed.

Women, men, work, and family. An expansionist theory.

The lives of women and men, the relationships that they establish, and their work have changed dramatically in the past 50 years, but the dominant theories driving research in these areas have not. In this article, the authors argue that the facts underlying the assumptions of the classical theories of gender and multiple roles have changed so radically as to make the theories obsolete. Moreover, a large body of empirical data fails to support the predictions flowing from these theories. Yet the development of new theory for guiding research and clinical practice has not kept pace. The authors attempt to fill this theoretical gap by reviewing the research literature and articulating an expansionist theory of gender, work, and family that includes four empirically derived and empirically testable principles better matched to todays realities.

Is There a Universal Positivity Bias in Attributions? A Meta-Analytic Review of Individual, Developmental, and Cultural Differences in the Self-Serving Attributional Bias

Researchers have suggested the presence of a self-serving attributional bias, with people making more internal, stable, and global attributions for positive events than for negative events. This study examined the magnitude, ubiquity, and adaptiveness of this bias. The authors conducted a meta-analysis of 266 studies, yielding 503 independent effect sizes. The average d was 0.96, indicating a large bias. The bias was present in nearly all samples. There were significant age differences, with children and older adults displaying the largest biases. Asian samples displayed significantly smaller biases (d = 0.30) than U.S. (d = 1.05) or Western (d = 0.70) samples. Psychopathology was associated with a significantly attenuated bias (d = 0.48) compared with samples without psychopathology (d = 1.28) and community samples (d = 1.08). The bias was smallest for samples with depression (0.21), anxiety (0.46), and attention-deficit/hyperactivity disorder (0.55). Findings confirm that the self-serving attributional bias is pervasive in the general population but demonstrates significant variability across age, culture, and psychopathology.

The Science of Sex Differences in Science and Mathematics

Amid ongoing public speculation about the reasons for sex differences in careers in science and mathematics, we present a consensus statement that is based on the best available scientific evidence. Sex differences in science and math achievement and ability are smaller for the mid-range of the abilities distribution than they are for those with the highest levels of achievement and ability. Males are more variable on most measures of quantitative and visuospatial ability, which necessarily results in more males at both high- and low-ability extremes; the reasons why males are often more variable remain elusive. Successful careers in math and science require many types of cognitive abilities. Females tend to excel in verbal abilities, with large differences between females and males found when assessments include writing samples. High-level achievement in science and math requires the ability to communicate effectively and comprehend abstract ideas, so the female advantage in writing should be helpful in all academic domains. Males outperform females on most measures of visuospatial abilities, which have been implicated as contributing to sex differences on standardized exams in mathematics and science. An evolutionary account of sex differences in mathematics and science supports the conclusion that, although sex differences in math and science performance have not directly evolved, they could be indirectly related to differences in interests and specific brain and cognitive systems. We review the brain basis for sex differences in science and mathematics, describe consistent effects, and identify numerous possible correlates. Experience alters brain structures and functioning, so causal statements about brain differences and success in math and science are circular. A wide range of sociocultural forces contribute to sex differences in mathematics and science achievement and ability—including the effects of family, neighborhood, peer, and school influences; training and experience; and cultural practices. We conclude that early experience, biological factors, educational policy, and cultural context affect the number of women and men who pursue advanced study in science and math and that these effects add and interact in complex ways. There are no single or simple answers to the complex questions about sex differences in science and mathematics.

Gender Similarities Characterize Math Performance

Gender differences in mathematics performance and ability remain a concern as scientists seek to address the underrepresentation of women at the highest levels of mathematics, the physical sciences, and engineering. Stereotypes that girls and women lack mathematical ability persist and are widely held by parents and teachers. Meta-analytic findings from 1990 (6) indicated that gender differences in mathematics performance in the general population were trivial, d = -.05. d = Mmales – Mfemales sw

A Meta-Analytic Review of Research on Gender Differences in Sexuality, 1993-2007.

In 1993 Oliver and Hyde conducted a meta-analysis on gender differences in sexuality. The current study updated that analysis with current research and methods. Evolutionary psychology, cognitive social learning theory, social structural theory, and the gender similarities hypothesis provided predictions about gender differences in sexuality. We analyzed gender differences in 30 reported sexual behaviors and attitudes for 834 individual samples uncovered in literature searches and 7 large national data sets. In support of evolutionary psychology, results from both the individual studies and the large data sets indicated that men reported slightly more sexual experience and more permissive attitudes than women for most of the variables. However, as predicted by the gender similarities hypothesis, most gender differences in sexual attitudes and behaviors were small. Exceptions were masturbation incidence, pornography use, casual sex, and attitudes toward casual sex, which all yielded medium effect sizes in which male participants reported more sexual behavior or permissive attitudes than female participants. Most effect sizes reported in the current study were comparable to those reported in Oliver and Hydes study. In support of cognitive social learning theory, year of publication moderated the magnitude of effect sizes, with gender differences for some aspects of sexuality increasing over time and others decreasing. As predicted by social structural theory, nations and ethnic groups with greater gender equity had smaller gender differences for some reported sexual behaviors than nations and ethnic groups with less gender equity. Gender differences decreased with age of the sample for some sexual behaviors and attitudes.