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1.
Rats were allowed to forage in a simulated natural environment made up of eight food sources (patches) each containing a fixed number of pellets. Two of the eight contained an extra supply of peanuts. The peanut patches were signaled by an olfactory/visual cue located at the bottom of the ladder leading to the patch. In successive phases the number of sessions per day, height of the patches, and availability of peanuts were manipulated. Subjects showed evidence of discrimination learning under these conditions, although the degree of discriminatory behavior varied as a function of environmental manipulations. Assessment of behavior within foraging sessions showed that subjects systematically changed their patterns of utilization of patches across time. Sampling or exploration, as well as food reinforcement, seem implicated in these results.  相似文献   
2.
In many classification problems, one often possesses external and/or internal information concerning the objects or units to be analyzed which makes it appropriate to impose constraints on the set of allowable classifications and their characteristics. CONCLUS, or CONstrained CLUStering, is a new methodology devised to perform constrained classification in either an overlapping or nonoverlapping (hierarchical or nonhierarchial) manner. This paper initially reviews the related classification literature. A discussion of the use of constraints in clustering problems is then presented. The CONCLUS model and algorithm are described in detail, as well as their flexibility for use in various applications. Monte Carlo results are presented for two synthetic data sets with appropriate discussion of the resulting implications. An illustration of CONCLUS is presented with respect to a sales territory design problem where the objects classified are various Forbes-500 companies. Finally, the discussion section highlights the main contribution of the paper and offers some areas for future research.We wish to thank C. Mallows and J. D. Carroll for some helpful technical discussion and L. Clark and D. Art for their valuable computer assistance. We also wish to thank H. Pollak, R. Gnanadesikan, and J. Kettenring for their thorough reviews of a previous draft of this paper. Finally, we acknowledge helpful comments of the editor and two anonymous reviewers.  相似文献   
3.
Work-related pressures perceived by PE teachers have been suggested to affect their motivation and behaviour. This study aims to contribute to the existing literature on this topic. Through two different objectives. First, the role of perceived pressures in the prediction of teachers’ motivation and, in turn, on their feasibility beliefs to implement motivational strategies is tested through a SEM. Secondly, PE teachers’ profiles according to the different types of perceived pressures are established and compared in terms of motivational outcomes and feasibility beliefs. A total of 217 PE teachers completed validated questionnaires. Results showed that, as hypothesized, pressures negatively predicted needs satisfaction, which, in turn, positively predicted feasibility beliefs. Three profiles emerged in the cluster analysis. Regarding to these profiles, teachers who were low on perceived pressures displayed the most adaptive pattern; teachers who reported high time constraints pressures underline the detrimental role that this type of pressure plays on both teacher and teaching outcomes. Implications for educational policy and practice are discussed.  相似文献   
4.
Preventing antisocial behavior in the schools   总被引:1,自引:0,他引:1  
Multiple correlates and determinants of antisocial behavior within the home, community, and school are reviewed. Due to the school's pivotal role in our society, an emphasis is placed on how our schools contribute to antisocial behavior, and what educators can do to prevent anti-social behavior and related attendance problems. A variety of contextual factors and setting events within our schools appear to be major contributors to antisocial behavior, and some of the same factors identified within the schools also have been identified within the home. These setting events, rather than quick restrictive fixes, must be given more attention if we are to provide safe school environments-environments that durably prevent antisocial behavior and related attendance problems.  相似文献   
5.
Four groups of three subjects resided for 10 days within a continuously programmed environment. Subjects followed a behavioral program of contingently scheduled activities that determined individual and social behaviors. A triadic condition was in effect when all three subjects were required to select simultaneous access to a group area before it became available for a social episode. A dyadic condition was in effect when access to a group area was permitted to any combination of two, and only two, subjects. The effects of these two conditions on individual and social behaviors were studied in reversal designs with several successive days devoted to each condition. Results showed that durations of social activities and synchronization of individual activities were greater during triadic conditions than during dyadic conditions. Under both conditions, wake-sleep cycles departed from a typical day-night rhythm for most subjects. Instances when subjects did not respond to each others' attempts to initiate conversations using the intercom were generally more frequent during dyadic than triadic conditions. Physical distance during triadic social episodes was found to be related to sociability levels during dyadic conditions.  相似文献   
6.
Rats were required to earn their food in a large room having nine boxes placed in it, each of which contained food buried in sand. In different phases of the experiment the amount of time allowed for foraging, the amount of food available in each food patch, and the location of the different available amounts were varied. The rats exhaustively sampled all patches each session but seemed to have fairly strong preferences for certain locations over others. If position preferences were for patches containing small amounts of food, the sensitivity to amount available was increased so that when location was compensated for, a pattern of optimal foraging was evident. The importance of environmental constraints in producing optimal behavior and the relation of the observed behavior to laboratory findings are discussed.  相似文献   
7.
The present study examined the impact of emotional expressiveness in toddlers’ environments on their emotion understanding. Primary caregivers of 35 toddlers completed two surveys regarding the family’s emotional expressiveness and the primary caregiver’s expressivity. Toddlers participated in the Affective Knowledge Test to measure emotion understanding. Toddler emotion understanding related to primary caregiver expressivity, but not family expressiveness. Further, toddler emotion understanding related to primary caregiver Impulse Strength, but not Negative or Positive Emotionality. This suggests that primary caregivers with more impulsive emotional response tendencies may help their children to identify associations between emotional events and reactions.  相似文献   
8.
The present study firstly establishes physical education (PE) teachers’ motivational profiles based on their autonomous motivation, controlled motivation and amotivation and, secondly, investigates how different PE teachers’ motivational profiles differ in terms of certain maladaptive antecedents (i.e. psychological need frustration, pressures perceived at work and burnout). It also addresses the differences in their students’ perception of autonomy support, psychological need satisfaction and autonomous motivation. A total of 105 PE teachers and their 2164 students completed validated questionnaires. Four profiles were retained in the cluster analysis. Results showed that teachers who were high on autonomous motivation displayed the most optimal pattern of outcomes, whereas teachers who were high on amotivation showed the opposite pattern. Analysis of the established profiles suggested that the experience of controlled motivation was linked with maladaptive outcomes among both teachers and students. Implications for educational policy and practice are discussed.  相似文献   
9.
10.
Autonomous vehicle (AV) technology is becoming one of the most promising alternatives to improve mobility for people with disabilities. Nevertheless, how people with disabilities perceive AV as transportation services has not been explored. Also, limited information exists about how public transit agencies comprehend and perceive autonomous vehicle transportation (AVT) services. This study discusses mobility issues for people with disabilities and explores the potential of AVT to serve that population, particularly those with visual impairments or physical disabilities. Researchers conducted six focus groups comprising people with disabilities (N = 23) and public transit service experts (N = 10) in Austin, Texas and Houston, Texas. Each session was audio-recorded and analyzed using conventional content analysis. This study identified people with disabilities’ mobility issues related to: (1) current transit services (including fixed-route and paratransit services) and (2) the quality of neighborhood built environments. Both people with disabilities and transit experts expected that AVT could mitigate current mobility issues, especially in improved built environments. However, participants with disabilities also expressed concerns and anxieties regarding AVT. Transit experts agreed that more targeted strategies would be needed to overcome possible barriers to AVT for people with disabilities. This study provides insights on shaping AVT strategies and policies relevant to improving mobility for people with disabilities.  相似文献   
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