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121.
Training practices for elite soccer players should take into account specific technical, tactical and physical components. As a consequence of these demands small-sided games (SSGs) have become a popular conditioning tool that replicate the demands encountered during match play. The aim of this investigation was to examine how the manipulation of exercise to rest ratio, within the same overall duration, affected both physical and technical outcomes during SSGs in elite youth soccer. Twelve elite youth soccer players participated in three variations of eight minute 6v6 SSGs. The three variations included eight minutes continuous, 2 × 4 min and 4 × 2 min. Players perceived the continuous 8 min block as the hardest (4.5 ± 1.5 AU), followed by the 2 × 4 min (3.9 ± 1.4 AU) and the 4 × 2 min (3.3 ± 1.4 AU), although no difference in mean HR or physical measures via GPS analysis between SSGs was evident. From the technical perspective, only goals scored reached significance, with post hoc analysis identifying the number of goals scored were significantly higher during the 4 × 2 min and 2 × 4 min SSGs compared to 8 min continuous block. These results show that subjective ratings of exertion differed between conditions, but only minor technical manipulations were observed by adjusting work to rest ratios, with no significant effect on physical performance. 相似文献
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Lavinia Tan Timothy D. Hackenberg 《Journal of the experimental analysis of behavior》2015,104(3):296-314
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Traditional methods for deriving property‐based representations of concepts from text have focused on either extracting only a subset of possible relation types, such as hyponymy/hypernymy (e.g., car is‐a vehicle ) or meronymy/metonymy (e.g., car has wheels ), or unspecified relations (e.g., car — petrol ). We propose a system for the challenging task of automatic, large‐scale acquisition of unconstrained, human‐like property norms from large text corpora, and discuss the theoretical implications of such a system. We employ syntactic, semantic, and encyclopedic information to guide our extraction, yielding concept‐relation‐feature triples (e.g., car be fast , car require petrol , car cause pollution ), which approximate property‐based conceptual representations. Our novel method extracts candidate triples from parsed corpora (Wikipedia and the British National Corpus) using syntactically and grammatically motivated rules, then reweights triples with a linear combination of their frequency and four statistical metrics. We assess our system output in three ways: lexical comparison with norms derived from human‐generated property norm data, direct evaluation by four human judges, and a semantic distance comparison with both WordNet similarity data and human‐judged concept similarity ratings. Our system offers a viable and performant method of plausible triple extraction: Our lexical comparison shows comparable performance to the current state‐of‐the‐art, while subsequent evaluations exhibit the human‐like character of our generated properties. 相似文献
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The fears of 133 boys and girls aged 7 to 19, classified as educable mentally retarded (EMR), trainable mentally retarded (TMR), and specific learning disabled (SLD), were ascertained through self-report data and compared with those of 106 normal children aged 6 to 12. Similar developmental trends were found in all groups, with younger children reporting more unrealistic fears than older children. When mental age was calculated for the EMR and TMR children, their developmental trends closely approximated those of the normal children. In general, exceptional children were found to have a much wider range and a greater number of fears than normal children. Most fears were found to be realistic, learned, and dependent upon the child's intellectual and maturational level. 相似文献
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Chloe A. Hill 《Psychology & health》2013,28(1):41-56
A condom use promotion leaflet was designed for use with older teenagers in schools. The text targeted a series of cognitive and behavioural antecedents of condom use identified in the literature. Given previous evidence that motivational incentives can enhance the effectiveness of health promotion leaflets, the leaflet was presented in conjunction with a quiz and prize draw. Students were randomly assigned to either the intervention condition or a (no leaflet or incentive) control condition. Measures were taken immediately, pre-intervention and 4 weeks later from 404 students. The 20-min intervention successfully promoted six of the eight measured cognitions, namely (1) attitude towards using condoms with a new partner (2) attitude towards using condoms with a steady partner (3) normative beliefs in relation to preparatory actions (4) self-efficacy in relation to both preparatory actions and (5) condom use (6) intention to use condoms, as well as three measured preparatory actions, that is, purchasing condoms, carrying condoms and discussing condom use. The intervention did not increase condom use with steady or new partners but power to test intervention impact on condom use was curtailed. 相似文献
130.
The sunk cost effect occurs when an individual persists following an initial investment, even when persisting is costly in the long run. The current study used a laboratory model of the sunk cost effect. Two response alternatives were available: Pigeons could persist by responding on a schedule key with mixed ratio requirements, or escape by responding on a second key. In Experiment 1, mean response requirements for persistence and escape were varied across conditions. Pigeons persisted (committing the sunk cost error) when persisting increased the mean response requirement only slightly but not when persisting was sufficiently nonoptimal. Experiment 2 explored more systematically combinations of ratios and probabilities assigned to the schedule key. Persistence varied with the ratio of the mean global response requirements for persistence and escape. In Experiment 3, transitions between ratios were signaled. This reduced nonoptimal persistence, and produced some instances of a reverse sunk cost error--escaping when persistence was optimal. In Experiment 4, it was optimal to escape after the second-smallest ratio ever presented. Pigeons escaped at approximately the optimal juncture, especially in conditions with added signals. Overall, this series of experiments suggests that the sunk cost error may arise in part because persistence is the default behavioral strategy in situations where the contingencies for escape and persistence are insufficiently disparate and/or it is relatively difficult to discriminate when to escape. The study also demonstrates the utility of animal models of complex decision making situations. 相似文献