Comparing variances of correlated variables

A test is proposed for the equality of the variances ofk 2 correlated variables. Pitman's test fork = 2 reduces the null hypothesis to zero correlation between their sum and their difference. Its extension, eliminating nuisance parameters by a bootstrap procedure, is valid for any correlation structure between thek normally distributed variables. A Monte Carlo study for several combinations of sample sizes and number of variables is presented, comparing the level and power of the new method with previously published tests. Some nonnormal data are included, for which the empirical level tends to be slightly higher than the nominal one. The results show that our method is close in power to the asymptotic tests which are extremely sensitive to nonnormality, yet it is robust and much more powerful than other robust tests.This research was supported by the fund for the promotion of research at the Technion.     

Aesthetic interaction as fit between interaction attributes and experiential qualities

Designing an aesthetic interaction is an important issue for Interaction Design (ID) and Human-Computer Interaction (HCI). While a number of frameworks exist, the experimental study of potential underlying principles remains rare. In this paper, we suggest that particular interaction attributes (e.g., “fast”) are systematically related to particular experiential qualities (e.g., “feeling competent”) and that interaction “feels better” if interaction matches the intended experience. A laboratory study (N = 32) explores this notion by testing two different ways of interacting within the same activity (opening a wine bottle) in two different experiential scenarios (focusing on relatedness, focusing on competence). Two corkscrews with different interaction profiles were used: one assumed to support a feeling of competence and the other to support relatedness. As expected, we found systematic shifts in preferences for specific corkscrews, differences in affective experience and in the relationships between interaction attributes and experiential qualities depending on the fit of interaction to the experience.     

BUILDING CHARACTER: A LEADERSHIP ESSENTIAL

Character is an increasingly important topic of discourse and analysis, however, much of the research remains problematic and conceptual. Even less evidence exists of the nature of the relationship between character and leadership. This study examined self-reported character and associated demographic correlates among a sample of 238 Australian business leaders. Exploratory factor analysis identified three dimensions of character consistent with theory. These dimensions were examined in relation to demographic variables. After controlling for social desirability bias, few statistically significant demographic differences were found. Further research is recommended to validate the model of character developed in our paper.

Parental Perceptions of Child Development Among Low-Income Mexican American Families

Parents' perceptions of child development are influenced by complex interactions among cultural, social, and economic factors. Insights into how parents from culturally diverse societies perceive the development of their children might explain why different cultural groups foster or value the development of different skills in their children. In this study, we explored the perceptions of child development among low income Mexican American parents. A series of ethnographic interviews were conducted with eight Mexican American families who had preschool children. Qualitative data analyses yielded three main themes that were important to these parents: family attitudes and values, changes, and adaptations. For these parents, the development of social attributes in children, that will enable them to function within their own cultural group, was as important as the development of cognitive or motor skills. Service providers, such as school and mental health personnel, should take into account cultural differences in parents' perceptions of the importance of various developmental milestones for their children when suggesting interventions typically used by parents in the dominant culture.     

Graded differential reinforcement: Response-dependent reinforcer amount

After key pecking had been autoshaped, six pigeons were exposed to a condition in which the duration of grain availability at the end of an 8-second trial depended on the number of responses emitted during the trial (0.25-second access to grain per response). This procedure, called correlated reinforcement, alternated across conditions with the automaintenance baseline in which the 8-second trial terminated with a constant 2.5-second access to grain. Two control procedures were run; in both, the reinforcer durations were yoked to those obtained in the last correlated session. In the yoked control no responses were required, but in the single-response yoked control at least one response was required to receive the yoked duration. The correlated condition maintained response rates above those produced by the two control conditions. These results may be accounted for by differential reinforcement.     

Tolerance to the effects of cocaine on performance under behavior-correlated reinforcement magnitude

Four pigeons responded under a fixed-interval 8-min schedule of food delivery in which the amount of food delivered at the end of each interval depended on performance during the interval (i.e., a correlated schedule). Specifically, duration of access to grain was contingent upon the number of responses made during the first 4 min of the interval. This differential outcome did not affect response rates or patterning relative to performance under a simple fixed-interval 8-min schedule. Behavior under the correlated schedule was then investigated under doses of cocaine ranging from 0.3 to 10.0 mg/kg. A bitonic dose-response function was obtained for response rates and the time with head in the food hopper, whereas dose-dependent decreases were observed in the mathematical index of curvature (Fry, Kelleher, & Cook, 1960). The dose that produced the greatest increase in the head-in-hopper time was then administered prior to each session. Following repeated administration of cocaine, disruptions in response patterning were attenuated for all 4 pigeons; tolerance was also observed to the rate-increasing effects and increased head-in-hopper time for 2 pigeons after chronic cocaine administration. Tolerance therefore developed despite the fact that the initial effect of cocaine was to increase the amount of food obtained.     

论医患关系的法律属性

医事法（又称卫生法）究竟是属于民法的调整范畴还是属于行政法的范畴,国内学术界争议很大。从医学科学与医疗行为的本质特征看,医患关系并不具备民事法律关系所必须具备的主体平等、双方自愿及等价有偿互惠互利三大特征中的任何一个特征。同时也不存在行政主体与行政相对人的关系。为此,首次提出医事法既不调整横向的民事法律关系,也不调整纵向的行政法律关系,而是调整斜向的医事法律关系的一门独立的法律体系的理论。     

非参数认知诊断方法下诊断结果的概率化表征

非参数认知诊断分类方法非常适合课堂评估,其诊断结果采用0-1形式而缺乏概率化表征,不能精细地区分被试属性掌握程度的差异或变化,还缺乏可用于评价真实测验分类结果的信度和效度指标。要刻画被试属性掌握程度的差异,首要的问题是要为非参数认知诊断方法提供一种可以量化属性掌握概率的方法。针对此问题,基于二项分布和玻尔兹曼分布提出非参数认知诊断方法下诊断结果的概率化表征方法,并用于构建分类准确性和分类一致性指标。模拟研究与实测数据分析结果显示：概率化表征方法与非参数认知诊断方法的分类结果高度一致;概率化表征方法与认知诊断模型所得的属性掌握概率十分接近;概率化表征方法所得的属性（模式）掌握概率可用于计算属性（模式）分类准确性和分类一致性指标,在实际测验情景下可作为信度和效度指标,评价诊断结果的重测一致率和判准率。     

Sound Body,Sound Mind? The Interrelation Between Health Change and Personality Change in Old Age

Personality development is characterized by increasing maturation, that is, people become more conscientious, agreeable and emotionally stable as they age. In late life, however, these trends seem to be reversed. Because many changes and transitions in older age are related to health, we investigated correlated changes in health problems and personality traits, the sources of health changes in later life and the directionality of effects. Our sample consisted of older adult twins, aged 64–85 years at time 1 (n = 410; 135 male/275 female; 134 monozygotic/63 dizygotic twin pairs), assessed at two different time points about five years apart, and we ran bivariate latent change and latent change twin model analyses. Increasing health problems were associated with decreases in agreeableness, extraversion, emotional stability and conscientiousness. Changes in health problems were only due to environmental influences, implying that the association between health and personality changes was exclusively environmental. Directional effects were largely absent, but health and personality were significantly related at the second measurement occasion (age 69–89 years). Our results support the link between health change and personality change in late life and spark the assumption of normative personality adaptations to deterioration of health status as a means of developmental regulation. Copyright © 2017 European Association of Personality Psychology     

A three city comparison of the public's knowledge and attitudes about AIDS

A survey of knowledge, beliefs and attitudes about AIDS was administered simultaneously in San Francisco, New York and London to a total of 399 persons. The aim was to investigate how such knowledge and attitudes may he influenced by social and cultural contexts, as well as by disease epidemiology. Across all samples of the general public (excluding risk group members) in the three cities, general fear of AIDS and anti-gay attitudes were significantly negatively correlated with knowledge about AIDS. In the London sample, general fear of AIDS and anti-gay attitudes were significantly and positively associated with both sexual and general health behavior change. Only sexual behavior change, however, was significantly correlated with general fear of AIDS and anti-gay variables for the New York sample. Neither of these variables was significantly associated with behavior change of any kind in the San Francisco sample. We accounted for these inter-city differences by proposing a four-stage model of public response to an epidemic over time. Our data support the need for specific programs aimed at the general public that take into account sociocultural and AIDS epidemiologic differences across different sociocultural contexts.