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41.
The correlation between short-term retention of the outcome of the preceding response and overall learning proficiency was investigated for serial reversal learning. Pigeons were trained to asymptote on a serial reversal problem and then were presented a percentage reinforcement schedule where only some correct trials were rewarded. Nonrewarded correct trials were treated exactly as incorrect trials. The difference in error probability following the two types of correct trials was then used as a measure of short-term retention. When intertrial intervals (ITI) were short (6 sec), substantial differences occurred. When the ITI's were increased, the difference in accuracy declined regularly to no difference at an ITI of 60 sec. This demonstration of a short-term retention gradient, coupled with the finding that overall reversal learning was much better with the shorter ITI's, suggests that a primary mechanism of improvement in serial reversal learning is the acquisition of a conditional discrimination based on the outcome of the preceding response.  相似文献   
42.
43.
This paper proposes an approach for strategic revenue management under uncertainty for real estate projects. It integrates three modelling techniques: first, artificial neural network integrated support vector machines for forecasting the profit and loss‐making real estate residential projects; second, analytical network process approach using decision making trials and evaluation laboratory methodology for establishing interrelationships among factors; and third, multiobjective genetic algorithm approach for obtaining optimal numbers and types of apartments in a real estate project. We compare the respective revenues generated with the new number of apartments and price from the suggested revenue maximization model and that of the old practiced one through a case study of India. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
44.
The sociological literature has produced a remarkably consistent picture of the quantitative patterns of religious disaffiliations in Western countries. This article argues, and demonstrates, that strong changes in a social context may lead individuals to disaffiliate rapidly, leading to very different aggregate effects from those in the “western model.” We use the unique situation of the separation of Germany from 1949 to 1989 and its subsequent reunification as a “natural experiment” to show just how much the relationships routinely found can be disrupted under changed conditions. The state socialist “treatment” affected religious disaffiliations in East Germany profoundly as it (a) made disaffiliations 10 times more probable in the East than in the West in the 1950s and 1960s, (b) shielded East German church members from factors that led to mass disaffiliations in the West in the late 1960s and early 1970s, (c) reversed the education‐disaffiliation link in the East, thus making disaffiliation more likely among the less educated, and (d) led to an especially strong increase in disaffiliations in the East right after the reunification  相似文献   
45.
In jurisdictions throughout the United States, thousands of sexual assault kits (SAKs; also known as a “rape kits”) have not been submitted by the police for forensic DNA testing. DNA evidence may be helpful to sexual assault investigations and prosecutions by identifying perpetrators, revealing serial offenders through DNA matches across cases, and exonerating those who have been wrongly accused. This paper describes a longitudinal action research project conducted in Detroit, Michigan after that city discovered approximately 11,000 untested sexual assault kits in a police department storage facility. We conducted a root cause analysis to examine individual, organizational, community, and societal factors that contributed to the development of the rape kit backlog in Detroit. Based on those findings, we implemented and evaluated structural changes to increase staffing, promote kit testing, and retrain police and prosecutors so that cases could be reopened for investigation and prosecution. As we conducted this work, we also studied how this action research project impacted the Detroit criminal justice system. Participating in this project changed stakeholders’ attitudes about the utility of research to address community problems, the usefulness of DNA evidence in sexual assault cases, and the impact of trauma on survivors. The results led to new protocols for SAK testing and police investigations, and new state legislation mandating SAK forensic DNA testing.  相似文献   
46.
Women of Haitian descent living in the Dominican Republic experience oppression due to their gender, ethnicity, and economic status. They also exhibit high rates of participation in evangelical Christian communities, a paradoxical finding given the restricted roles women have traditionally played in these settings. The goals of this study were to explore the perceived benefits of participation in evangelical communities and the setting characteristics that lead to these benefits. The research team interviewed 19 current and former church participants aged 18–59. Thematic analysis revealed three perceived benefits of congregational life. Participants viewed their participation as: (a) an opportunity for personal growth and development; (b) protective against negative social influences; and (c) providing social support in the face of life challenges. In addition, dependable, expected, and reciprocal relational support was a key characteristic of evangelical communities. Findings extend the current understanding of how religious communities enhance well‐being for marginalized women through social support networks. Findings also explore the dialectical nature of settings as both empowering and disempowering. Implications for future interventions are discussed.  相似文献   
47.
We investigated ADHD symptoms and CU traits as predictors of violent media use in adolescence, controlling for delinquency and ODD symptoms. The effects on of disinhibition and arousal to negative stimuli, core characteristics of ADHD symptoms and CU traits, and of gender were investigated. At age 15, 88 adolescents, 50 % boys reported on CU traits, ADHD symptoms and delinquency. Parents rated the adolescents’ CU traits, ADHD‐ and ODD symptoms. At age 16, adolescents reported on their media habits and performed tests of disinhibition and arousal to negative stimuli. Boys had higher levels of CU traits and violent media use and girls had higher levels of arousal to negative pictures. CU traits and inattention symptoms predicted violent media use, the latter association applying only to boys, with CU traits being the strongest predictor. Low arousal to threat pictures explained variance in violent media use, above CU traits. Attraction to violent media seems affected by problem behaviors, with CU traits coming forth as especially important.  相似文献   
48.
Identifying the specificity of students’ individual interest in physical education is necessary to capture the different facets of this construct. In contrast to existing questionnaires in education which assess the multidimensionality of individual interest, the current scale used in physical education consists of a single‐item measurement which rates students’ individual interest for multiple physical activities taught during lessons. Even if this single‐item rating provides a basis for classifying interest relative to others, it does not provide information about the nature and internal components of individual interest. Therefore, the purpose of this study was to develop a valid and reliable questionnaire measuring the multidimensionality of students’ individual interest in physical education. Four stages were followed: (1) the development of a preliminary version based on the findings of a literature review on individual interest and a committee process validation; (2) a first study conducted on 481 secondary school students to establish the factor structure, and internal reliability of this questionnaire; (3) a second study based on 243 secondary school students to confirm its factor structure and to test its temporal stability; and finally, (4) a third study with 253 students to test its concurrent validity. The final form of the questionnaire consists of a three‐factor structure based on 14 items that measure students’ individual interest in physical education: positive affect and willingness to reengage (five items), stored utility value (four items), and stored attainment value and knowledge‐seeking intentions (five items).  相似文献   
49.
Three experiments investigated whether and why sharing experiences of social exclusion or social acceptance with others strengthens social bonds. Participants experienced either social exclusion or social acceptance alongside another co‐participant who either also experienced the same outcome, or experienced a different outcome, as them. Multilevel modeling results showed that participant dyads who shared the experience of social exclusion or social acceptance felt closer to each other than those who experienced different outcomes, and that perceived similarity mediated the effect of shared experiences on social bonds. Interestingly, participants felt closer to one another after having shared social acceptance, more so than when they have shared social exclusion. Implications of the present findings are interpreted in light of theories of social exclusion, shared experiences, and social bonding.  相似文献   
50.
Knowledge and understanding about the impact of cumulative adverse experiences on the health and wellbeing of children, adolescents, and adults has rapidly expanded over the past 30 years. Despite the invaluable attention and support this proliferation has drawn to the importance of early childhood experiences, we believe that it is time to move beyond broad indices of risk and toward more specific and individualized understanding of how risk exposures are linked to clinical outcomes in young children. Within infant and early childhood mental health, there is a need for greater specificity in linking adverse caregiving experiences in early life to psychopathology in children. We highlight a framework distinguishing experiences of trauma from experiences of deprivation and use the examples of posttraumatic stress disorder and reactive attachment disorder to demonstrate how greater specificity in our understanding of early adverse caregiving can lead to more accurate and targeted diagnosis and treatment for young children. Both researchers and clinicians benefit from an approach to gain a greater appreciation of the links between specific types of experiences and outcomes in the children that we serve.  相似文献   
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