Are individual differences in temperament of relevance to Gibson's theory of affordances?

The ambitious scope, complexity, and difficulty of Gibson’s project in proposing the theory of affordances are captured nicely by the words of Gibson’s biographer, Ed Reed:
“Gibson was convinced that the theory of affordances, in
conjunction with the concepts of information, persistence, and
change, would enable him to transcend the ancient debate between
subjectivity and objectivity and to resolve the mind-body problem. …
[H]e was offering a new approach to problems of psychology, one
that he believed would not sink in the morass that have engulfed
previous psychologies.” (Reed, 1988, p. 280).
These characteristics of the theory of affordances are further evidenced in the debates about the nature of affordances presented in the suite of papers in Ecological Psychology, Volume 12(1). In this paper we propose an elaboration of the notion of affordance by suggesting that those persisting individual differences in behaviour described as temperamental differences (e.g., differences on a dimension of temperament anchored at one end by behaviour described as ‘outgoingness’ and at the other by behaviour described as ‘avoidance’) can be integrated into the theory of affordances. We argue that such integration is consistent with Gibson’s project as reflected in Reed’s words, and as part of our argument, draw parallels between the integration of temperament with the theory of affordances and the way in which individual differences in body dimensions are incorporated in the theory. We also outline some empirical tests of our proposition.

The mythical properties of police body-worn cameras: A solution in the search of a problem

Over the past few years, Australian police agencies have begun to enthusiastically introduce body-worn cameras on police personnel. These devices are now either implemented or under trial across the country. There is also an emergent ‘surveillance consensus’ (Hempel and Töpfer 2009) concerning their use amongst Australian police. While more detailed empirical examination of information flows that shape this surveillance consensus is warranted, this contribution to the debate seeks to draw from policing scholarship to critically explore the intersections between the rationalizations for body-worn cameras and the broader policing scholarship. More directly, body-worn cameras cannot be understood in narrow instrumental terms, but must be located within the broader literature on governing police and the law and order politics that surrounds many contemporary police and criminal justice reforms (Cox 2015; Gregg and Wilson 2015). I begin with a summary of the introduction of body-worn cameras in Australia. The article then identifies five problems body-worn cameras purportedly address and provides a brief case summary indicating how current ‘privacy protections’ fail to establish real limits to the collection, use, and dissemination of images from body-worn cameras.

Methodological problem with comparing increases in different measures of body weight

Background A number of studies have compared proportional increases over time in waist circumference (WC) and body mass index (BMI). However this method is flawed. Here, we explain why comparisons of WC and BMI must take into account the relationship between them. We used data from two cross-sectional US surveys (NHANES 1988-94 and 2005-06), and calculated the percentage change in the average BMI and the average WC between the two surveys, comparing the results with a regression analysis of changes in WC relative to BMI.

Findings The crude percentage change in BMI (5.8%) was marginally greater than for WC (5.1%). But these percentages cannot be directly compared, as the relationship between the measures is described by a regression equation with an intercept term that does not equal zero. The coefficient of time from the regression equation will determine whether or not WC is on average larger for a given BMI at the second compared with the first time point.

Conclusion Differences in the percentage change in WC and the percentage change in BMI cannot be usefully directly compared. Comparisons of increases in the two measures must account for the relationship between them as described by the regression equation.

Relationships between sport participation, problem alcohol use, and violence: A longitudinal study of young adults in Australia

There is a growing body of evidence suggesting a link between sport participation and violent behavior outside of the sporting context. However, there have been few studies that have investigated the basis of this relationship. The current study examined longitudinal relationships between sport participation, problem alcohol use, and various violent behaviors, and whether sport participation moderates relationships between problem alcohol use and violence. The sample comprised 2,262 young adults (55% female, age range at Time 1 = 17-24 years) from Victoria, Australia, surveyed in 2010 and 2012. When controlling for common risk factors, substance use, and past violence, sport participation was not associated with any violent behaviors 2 years later. However, sport participation moderated the relationship between problem alcohol use and fighting, whereby problem alcohol use was associated with engaging in fights 2 years later for sport participants, but not for nonparticipants. These findings suggest that it is not sport participation per se that influences later violence but the drinking norms or culture embedded within certain sporting contexts. Prevention approaches that address the drinking culture and social approval of excessive alcohol consumption within sporting contexts may reduce the incidence of violent behavior in the community.

Parent, peer and media influences on body image and strategies to both increase and decrease body size among adolescent boys and girls

This study investigated the nature of body image and body change strategies, as well as the sociocultural influences on these variables, among a group of 1,266 adolescents (622 males, 644 females). In particular, it investigated weight gain and increased muscle, as well as weight loss. It was found that females were less satisfied with their bodies and were more likely to adopt strategies to lose weight, whereas males were more likely to adopt strategies to increase weight and muscle tone. Respondents with higher body mass index (BMI) evidenced greater body dissatisfaction and more weight loss strategies, but there were no differences between BMI groups in weight gain or strategies to increase muscles. Weight gain and strategies to increase muscles were more likely to be undertaken by older adolescents, but there were no grade level differences in weight loss. Media influences to alter weight, as well as feedback from mother, father, and both male and female peers, were greater for females. There were few grade level or BMI differences in regard to any of the sociocultural influences. The importance of these findings in terms of providing a better understanding of factors which may lead to a disturbed body image and body change disorders, particularly among adolescent boys, is discussed.

Associations of physical activity with body weight and fat in men and women

OBJECTIVE: Increasing physical activity is strongly advocated as a key public health strategy for weight gain prevention. We investigated associations of leisure-time physical activity (LTPA) and occupational/domestic physical activity with body mass index (BMI) and a skinfold-derived index of body fat (sum of six skinfolds), among normal-weight and overweight men and women.

DESIGN: Analyses of cross-sectional self-report and measured anthropometric data.

SUBJECTS: A total of 1302 men and women, aged 18-78 y, who were part of a randomly selected sample and who agreed to participate in a physical health assessment.

MEASUREMENTS: Self-report measures of physical activity, measured height and weight, and a skinfold-derived index of body fatness.

RESULTS: Higher levels of LTPA were positively associated with the likelihood of being in the normal BMI and lower body fat range for women, but few or no associations were found for men. No associations were found between measures of occupational/domestic activity and BMI or body fat for men or women.

CONCLUSION: By using a skinfold sum as a more direct measure of adiposity, this study extends and confirms the previous research that has shown an association between BMI and LTPA. Our results suggest gender differences in the relationship of leisure-time physical activity with body fatness. These findings, in conjunction with a better understanding of the causes of such differences, will have important public health implications for the development and targeting of weight gain prevention strategies.

Social comparisons and negative affect as indicators of problem eating and muscle preoccupation among children

The present study examined the utilization of social comparison practices and the role of negative affect in predicting body dissatisfaction, problem eating, and muscle preoccupation among young children. Participants were 236 children aged between 8 and 10 years. Children's eating, exercising, and muscle concerns were examined using a modified version of the Children's Eating Attitudes Test (ChEAT), which included additional items pertaining to muscle bulk and exercising. Consistent with past findings, body mass index (BMI) was found to be the sole unique indicator of body dissatisfaction for both boys and girls. Utilization of social comparison practices with adults was the main unique indicator of the modified ChEAT factors for boys, while BMI was the main unique indicator of the modified ChEAT factors for girls. In addition, negative affect was associated with binging, food preoccupation, and social pressure to eat for boys and dieting and muscle preoccupation for girls. Findings are discussed in relation to previous studies with adolescents and adults.

Body image dissatisfaction among males across the lifespan- a review of past literature

Objective: Most past research has focused on body dissatisfaction among females. This paper provides a review and evaluation of studies that have examined body dissatisfaction among males. Body dissatisfaction in males has been associated with poor psychological adjustment, eating disorders, steroid use, exercise dependence, as well as other health behaviors. It is therefore important to understand the level of body dissatisfaction, as well as the factors that are related to this construct. Method: The review is divided into three sections: body dissatisfaction among children, adolescents and adults. Within each section, levels of body dissatisfaction are examined, as well as the research that relates to sociocultural influences on body dissatisfaction. Difficulties in drawing valid conclusions from the data due to methodological problems are highlighted. Results: From the current data, it would appear that there are strong similarities in the levels of body dissatisfaction of male and female children, with most children demonstrating high levels of body satisfaction. During adolescence, boys are about equally divided between wanting to lose weight and increasing weight, but there are few studies that have examined a desire for increased muscle size. In adulthood, men evidence a stronger desire to lose weight as they get older. Conclusion: Overall, past studies have primarily focused on questions that are relevant to females, and there is a need to conduct studies that evaluate areas of body dissatisfaction that have greater relevance for males. This will then allow a better understanding of the relationship between body dissatisfaction and psychological and behavioral problems experienced by males at all stages of the lifespan.

Direct current electric potential in an anisotropic half-space with vertical contact containing a conductive 3D body

Detailed studies of anomalous conductors in otherwise homogeneous media have been modelled. Vertical contacts form common geometries in galvanic studies when describing geological formations with different electrical conductivities on either side. However, previous studies of vertical discontinuities have been mainly concerned with isotropic environments. In this paper, we deal with the effect on the electric potentials, such as mise-`a-la-masse anomalies, due to a conductor near a vertical contact between two anisotropic regions. We also demonstrate the interactive effects when the conductive body is placed across the vertical contact. This problem is normally very difficult to solve by the traditional numerical methods. The integral equations for the electric potential in anisotropic half-spaces are established. Green’s function is obtained using the reflection and transmission image method in which five images are needed to fit the boundary conditions on the vertical interface and the air-earth surface. The effects of the anisotropy of the environments and the conductive body on the electric potential are illustrated with the aid of several numerical examples.

Adolescent body image and psychosocial functioning

Researchers have highlighted the significance of a poor body image in the development of dysfunctional eating but have systematically investigated few other outcomes. The authors examined the relationships between different aspects of body image and psychosocial functioning. Participants were 245 boys and 173 girls from Grades 8 and 9 (M age = 13.92 years, SD = 0.69 years). Respondents completed measures of physical attractiveness, body satisfaction, body image importance, body image behaviors, appearance comparison, social physique anxiety, self-esteem, depression, anxiety, and same-sex and opposite-sex relations. Whereas girls tended to report a more negative body image than did boys, the relevance of body image to self-esteem was similar for boys and girls. Concern about others' evaluation of their bodies was especially important in understanding low female self-esteem, whereas for boys, ratings of general attractiveness most strongly predicted self-esteem. The authors found a negative body image to be unrelated to symptoms of negative affect but to be strongly associated with poor opposite-sex peer relationships, especially among boys. A negative body image also affected same-sex relations among girls.

Understanding problem solving in requirements engineering : debating creativity with IS practitioners

RE is well-recognised as a creative problem solving activity by the systems development community. However, while substantial research has been conducted and knowledge gained about creativity in the general psychology of problem solving, creativity as it applies to RE remains a relatively unexplored area - one that has neither been comprehensively studied, nor highly recognised, as a research topic of importance. This paper attempts to address the above mentioned gap by presenting findings from a recent focus group study of creativity in RE as perceived by a group of RE practitioners. We provide a conceptual framework for understanding creativity in RE, which may be of use to requirements engineers attempting to enable more creative approaches and results, as well as adding to the existing, limited body of research in this area.

Problem of precision missile guidance: LQR and H‡ control frameworks

Addressed here is the precision missile guidance problem where the successful intercept criterion has been defined in terms of both minimizing the miss distance and controlling the missile body attitude with respect to the target at the terminal point. We show that the H∞ control theory, when suitably modified, provides an effective framework for the precision missile guidance problem. The existence of feedback controllers (guidance laws) is investigated for the case of finite horizon and non-zero initial conditions. Both state feedback and output feedback implementations are explored.

Dietary patterns throughout adult life are associated with body mass index, waist circumference, blood pressure, and red cell folate

Dietary patterns are important in the prevention of chronic disease; however, there are few studies that include repeat measures of dietary patterns. The objective of this study was to assess the relations between dietary patterns during adult life (at ages 36, 43, and 53 y) and risk factors for chronic disease at age 53 y. Participants of a longitudinal study of health completed a 5-d food diary at 3 occasions during adult life (n = 1265). Factor analysis was used to identify dietary patterns and a pattern score was calculated from the consumption of the food items in each dietary pattern. Means and 95% CI for dietary pattern scores were calculated for each risk factor category using random effects models adjusted for socio-demographic and health-related behaviors. In women, the fruit, vegetables, and dairy pattern was inversely associated with BMI (P < 0.004), waist circumference (P = 0.0007), blood pressure (P = 0.02), and was positively associated with red cell folate (P < 0.03). The ethnic foods and alcohol pattern was also inversely associated with blood pressure (P = 0.008), whereas the meat, potatoes and sweet foods pattern was positively associated with glycated hemoglobin (P = 0.01). In men, a mixed pattern was inversely associated with waist circumference (P = 0.02) and blood pressure (P = 0.01), whereas there were no significant associations with the ethnic foods and alcohol pattern. Specific dietary patterns throughout adult life were associated with chronic disease risk factors.

Stability of television viewing and electronic game/computer use in a prospective cohort study of Australian children: relationship with body mass index

Background
While much cross-sectional data is available, there have been few longitudinal investigations of patterns of electronic media use in children. Further, the possibility of a bi-directional relationship between electronic media use and body mass index in children has not been considered. This study aimed to describe longitudinal patterns of television viewing and electronic game/computer use, and investigate relationships with body mass index (BMI).
Methods
This prospective cohort study was conducted in elementary schools in Victoria, Australia. 1278 children aged 5–10 years at baseline and 8–13 years at follow-up had their BMI calculated, from measured height and weight, and transformed to z-scores based on US 2000 growth data. Weight status (non-overweight, overweight and obese) was based on international BMI cut-off points. Weekly television viewing and electronic game/computer use were reported by parents, these were summed to generate total weekly screen time. Children were classified as meeting electronic media use guidelines if their total screen time was ≤14 hrs/wk.
Results
Electronic media use increased over the course of the study; 40% met guidelines at baseline but only 18% three years later. Television viewing and electronic game/computer use tracked moderately and total screen time was positively associated with adiposity cross-sectionally. While weaker relationships with adiposity were observed longitudinally, baseline z-BMI and weight status were positively associated with follow-up screen time and baseline screen time was positively associated with z-BMI and weight status at follow-up. Children who did not meet guidelines at baseline had significantly higher z-BMI and were more likely to be classified as overweight/obese at follow-up.

Conclusion
Electronic media use in Australian elementary school children is high, increases with age and tracks over time. There appears to be a bi-directional association suggesting that interventions targeting reductions in either screen time or adiposity may have a positive effect on both screen time and adiposity.

Comparison of the structure of adolescent problem behavior in the United States and Australia

Some extant theory and empirical research suggests that youth problem behaviors, such as substance abuse and delinquency, reflect a single underlying dimension of behavior, whereas others suggest there are several different dimensions. Few studies have examined potential international differences in the structure of problem behavior, where cultural and policy differences may create more variation in behavior and different structures. This study explored the structure of problem behavior in two representative samples of youth (ages 12-17) from Maine and Oregon in the United States (N = 33,066) and Victoria, Australia (N = 8,500). The authors examined the degree to which data from the two countries produce similar model structures using indicators of problem behavior. Results show that the data are best represented by two factors, substance use and delinquency, and there appear to be more similarities than differences in the models across countries. Implications for understanding problem behavior across cultural and developmental groups and practical and policy implications are discussed.