Marilyn T. Zivian

Gender Differences in Population Versus Media Body Sizes: A Comparison over Four Decades

Mean body mass indices (BMIs, kg/m2)of North Americans aged 18 to 24 collected from 11national health surveys were compared to: Playboycenterfold models, Miss America Pageant winners,andPlaygirl models. The survey samples were representative of themix of different ethnic and racial groups in Canada andthe USA. No racial or ethnic information was availablefor either the Playboy women or the Miss America Pageant winners. Ninety percent of the Playgirlmen were white; 10%, black; 1.5%, Hispanic black; and.8%, American Samoan. From the 1950s to the present,while the body sizes of Miss America Pageant winners decreased significantly and the body sizes ofPlayboy centerfold models remained below normal bodyweight, the body sizes of Playgirl models and youngadult North American women and men increasedsignificantly. The increase in body size of Playgirl modelsappears to be due to an increase in muscularity, whereasthe increase in body size of young North American menand women is more likely due to an increase in body fat. Thus, in the 1990s, the body size andshape of the average young adult North American becameincreasingly different from the ideal being promoted bythe media. Furthermore the difference in male and female body sizes depicted by the media inthe 1990s was huge, whereas the difference between thebody sizes of 18- to 24-year-old North American womenand men was actually quite small. These discrepancies are discussed in relation to the differentsociocultural expectations for the two genders and theincreasing prevalence of body dissatisfaction reportedby both women and men.

Gender role conflict : the interaction of gender, gender role, and occupation

One hundred forty-nine middle class individuals (69 males and 80 females), approximately 80% of whom were Caucasian, participated in the present study. The study was designed to test the hypothesis that individuals whose gender role and occupation did not match (i.e., feminine individuals in predominantly male occupations or masculine individuals in predominantly female occupations) would experience more gender role conflict than individuals whose gender role and occupation matched. The hypothesis was supported. A feminine gender role predicted higher gender role conflict in predominantly male occupations, and lower gender role conflict in predominantly female occupations than a masculine gender role. A masculine gender role predicted the lowest gender role conflict scores in predominantly male occupations, and the highest in predominantly female occupations. Furthermore, higher masculinity scores were related to greater gender role conflict for females than males in more predominantly male occupations.

STAZ: interactive software for undergraduate statistics.

STAZ is an interactive computer program that demonstrates statistical concepts, many of which cannot be readily demonstrated using conventional methods. Use of dynamic graphics encourages active engagement with challenging statistical concepts. The program consists of 13 graphical demonstrations, most of which allow for interactive participation by students. A detailed Help file with guided explanations accompanies each demonstration. STAZ is a multiple document interface program that makes full use of Windows features, such as tiling, links, and multitasking. Designed to be used as a supplement for any undergraduate statistics course, STAZ may be used by either instructors in classroom settings or students working independently.

Absolute and relative perceptual codes in young children

Three experiments were conducted to ascertain whether young children’s perceptual codes, as evidenced by choice reaction times, were related to either the absolute difference or the ratio between stimuli. In Experiments 1 and 2, children were shown pairs of line lengths and were asked to choose either the longer or shorter line within each pair. In Experiment 3, children chose which of two birds on a map was closer to themselves or to the experimenter. In all three experiments, children’s reaction times were related to both the absolute differences and ratios between pairs of stimuli. The findings suggest that perceptual judgments in young children may be based on both absolute and relational codes.

The Accuracy of Diagnostic Radiology

Publisher Summary This chapter describes commonly used measures of accuracy, including their inherent advantages and shortcomings, and highlights possible interactions between research design and measures of accuracy within the context of screening mammography and computer-aided detection (CAD) in screening mammography. Sensitivity and specificity are basic measures of the accuracy of diagnostic tests. They also appear to be the most popular indices of diagnostic accuracy in the radiological literature. They are diagnostic accuracy descriptors that do not vary greatly among patient populations, but they can vary greatly among radiologists. Overall accuracy is also a popular index of diagnostic accuracy in the radiological literature, though perhaps somewhat less popular than sensitivity and specificity. The overall accuracy of a diagnostic test is calculated by adding hits and correct rejections and dividing by the total number of patients tested. Signal detection theory estimates diagnostic accuracy by analyzing the receiver (or relative) operating characteristic. Receiver operating characteristic (ROC) curves are obtained by plotting hit rate [hits/(hits + misses)] on the y-axis and false alarm rate [false alarms/(correct rejections + false alarms)] on the x-axis of a two-dimensional graph. Each point on the ROC curve corresponds to a pair of hit and false alarm rates that result from use of a specific cut-off value. The ROC curve enables a direct visual comparison of two or more diagnostic tests at all possible cut-points, and hit and false alarm rates can be easily read from the graph. Currently, the area under the ROC curve (AUC) is the preferred and most popular signal detection theory index of accuracy and the values for AUC can range from 0.0 to 1.0.