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This article attempts to characterize the general problem of selecting methods for decision-making. The traditional rational approach to choice is from economics, which offers expected-value maximization. The task environment of decision method selection, however, does not seem to provide the data necessary for carrying out the expected-value calculations. Our approach uses methods from the field of cognitive science. We develop the notion of domain size in fields such as chess, borrowing the concept of a chunk from human memory. We then develop a heuristic rule for choiceamongmethods. We propose this rule as one of many possible rules.  相似文献   
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The 100 ms ruling for false start disqualification at athletic competitions governed by the International Association of Athletics Federations has been in force since the early 1990s. Throughout this period, there have been marked changes to the rules that govern the disqualification of athletes from sprint events incorporating starts from blocks. This study analysed all available World and European Championship response-time (RT) data from 1999 to 2014 to examine effects of rule changes on competition RT at major championships. The exponentially modified Gaussian distribution was used to model RT and make comparisons relative to athletes’ sex, ruling periods and competition rounds. Revised RT thresholds of 115 ms and 119 ms were identified for men and women, respectively, indicating that the current 100 ms rule could result in some false starts not being detected in competitive athletics. The study proposes that when using existing International Association of Athletics Federations approved systems, the false start detection threshold should be increased and that men and women athletes should have different thresholds because of substantial evidence of a sex-based difference in RT in elite-standard athletes.  相似文献   
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In this monograph, we argue for the establishment of a developmental science of politics that describes, explains, and predicts the formation and change of individuals’ political knowledge, attitudes, and behavior beginning in childhood and continuing across the life course. Reflecting our goal of contributing both theoretical conceptualizations and empirical data, we have organized the monograph into two broad sections. In the first section, we outline theoretical contributions that the study of politics may make to developmental science and provide practical reasons that empirical research in the domain of politics is important (e.g., for identifying ways to improve civics education and for encouraging higher voting rates among young adults). We also review major historical approaches to the study of political development and provide an integrative theoretical framework to ground future work. Drawing on Bronfenbrenner's ecological systems model as an organizing scheme and emphasizing social justice issues, we describe how factors rooted in cultural contexts, families, and children themselves are likely to shape political development. In the second section of the monograph, we argue for the importance and utility of studying major political events, such as presidential elections, and introduce the major themes, rationales, and hypotheses for a study of U.S. children's views of the 2016 U.S. presidential election. In addition, we apply a social-justice lens to political thought and participation, addressing the role of gender/sex and race/ethnicity in children's political development broadly, and in their knowledge and views of the 2016 U.S. presidential election specifically. In interviews conducted within the month before and after the election, we examined two overarching categories of children's political attitudes: (a) knowledge, preferences, and expectations about the 2016 election, and (b) knowledge and attitudes concerning gender/sex and politics, particularly relevant for the 2016 election given Hillary Clinton's role as the first female major-party candidate for the presidency. Participants were 187 children (101 girls) between 5 and 11 years of age (M = 8.42 years, SD = 1.45 years). They were recruited from schools and youth organizations in five counties in four U.S. states (Kansas, Kentucky, Texas, and Washington) with varying voting patterns (e.g., Trump voters ranged from 27% to 71% of county voters). The sample was not a nationally representative one, but was racially diverse (35 African American, 50 Latinx, 81 White, and 21 multiracial, Asian American, Middle Eastern, or Native American children). In addition to several child characteristics (e.g., age, social dominance orientation [SDO]), we assessed several family and community characteristics (e.g., child-reported parental interest in the election and government-reported county-level voting patterns, respectively) hypothesized to predict outcome variables. Although our findings are shaped by the nature of our sample (e.g., our participants were less likely to support Trump than children in larger, nationwide samples were), they offer preliminary insights into children's political development. Overall, children in our sample were interested in and knowledgeable about the presidential election (e.g., a large majority identified the candidates correctly and reported some knowledge about their personal qualities or policy positions). They reported more information about Donald Trump's than Hillary Clinton's policies, largely accounted for by the substantial percentage of children (41%) who referred to Trump's immigration policies (e.g., building a wall between the United States and Mexico). Overall, children reported as many negative as positive personal qualities of the candidates, with negative qualities being reported more often for Trump than for Clinton (56% and 18% of children, respectively). Most children (88%) supported Clinton over Trump, a preference that did not vary by participants’ gender/sex or race/ethnicity. In their responses to an open-ended inquiry about their reactions to Trump's win, 63% of children reported negative and 18% reported positive emotions. Latinx children reacted more negatively to the election outcome than did White children. Girls’ and boys’ emotional responses to the election outcome did not differ. Children's personal interest in serving as U.S. president did not vary across gender/sex or racial/ethnic groups (overall, 42% were interested). Clinton's loss of the election did not appear to depress (or pique) girls’ interest in becoming U.S. president. With respect to the role of gender/sex in politics, many children (35%) were ignorant about women's absence from the U.S. presidency. Only a single child was able to name a historical individual who worked for women's civil rights or suffrage. Child characteristics predicted some outcome variables. For example, as expected, older children showed greater knowledge about the candidates than did younger children. Family and community characteristics also predicted some outcome variables. For example, as expected, participants were more likely to support Trump if they perceived that their parents supported him and if Trump received a greater percentage of votes in the children's county of residence. Our data suggest that civic education should be expanded and reformed. In addition to addressing societal problems requiring political solutions, civics lessons should include the histories of social groups’ political participation, including information about gender discrimination and the women's suffrage movement in U.S. political history. Providing children with environments that are rich in information related to the purpose and value of politics, and with opportunities and encouragement for political thought and action, is potentially beneficial for youth and their nations.  相似文献   
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Measurement of ground reaction force (GRF) in running provides a direct indication of the loads to which the body is subjected at each foot-ground contact, and can provide an objective explanation for performance outcomes. Traditionally, the collection of three orthogonal component GRF data in running requires an athlete to complete a series of return loops along a laboratory based runway, within which a force platform is embedded, in order to collect data from a discrete footfall. The major disadvantages associated with this GRF data collection methodology include the inability to assess multiple consecutive foot contacts and the fact that measurements are typically confined to the laboratory. The objective of this research was to investigate the potential for wearable instrumentation to be employed, in conjunction with artificial neural network (ANN) and multiple linear regression (MLR) models, for the estimation of GRF in middle distance running. A modular wearable data acquisition system was developed to acquire in-shoe force (ISF) data. Matched data sets from wearable instrumentation (source data) and force plate (target data) records were collected from elite middle-distance runners under controlled laboratory conditions for the purposes of ANN and MLR model development (MD) and model validation (MV). In terms of statistical measures of prediction accuracy the MLR model was found to provide a superior level of accuracy for the prediction of the vertical and medio-lateral components of GRF and alternatively, the ANN model provided the most accurate predictions of the anterior-posterior component of GRF. The prediction accuracy of each component of GRF was found to be governed by the inherent signal variability, in which case the vertical and anterior-posterior components were more reliable and subsequently predicted significantly more accurately than the medio-lateral component. The emerging capability for obtaining continuous GRF records from wearable instrumentation has the potential to permit unprecedented quantification of training stress and competition demands in running.  相似文献   
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Multistage, ultra-endurance events in hot, humid conditions necessitate thermal adaptation, often achieved through short term heat acclimation (STHA), to improve performance by reducing thermoregulatory strain and perceptions of heat stress. This study investigated the physiological, perceptual and immunological responses to STHA prior to the Marathon des Sables. Eight athletes (age 42 ± 4 years and body mass 81.9 ± 15.0 kg) completed 4 days of controlled hyperthermia STHA (60 min·day?1, 45°C and 30% relative humidity). Pre, during and post sessions, physiological and perceptual measures were recorded. Immunological measures were recorded pre-post sessions 1 and 4. STHA improved thermal comfort (P = 0.02), sensation (P = 0.03) and perceived exertion (P = 0.04). A dissociated relationship between perceptual fatigue and Tre was evident after STHA, with reductions in perceived Physical (P = 0.04) and General (P = 0.04) fatigue. Exercising Tre and HR did not change (P > 0.05) however, sweat rate increased 14% (P = 0.02). No changes were found in white blood cell counts or content (P > 0.05). Four days of STHA facilitates effective perceptual adaptations, without compromising immune status prior to an ultra-endurance race in heat stress. A greater physiological strain is required to confer optimal physiological adaptations.  相似文献   
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This paper gives background information on early childhood services in Ireland and presents the results of a survey of the preschool experiences of 1065 children. The results of the survey suggest that the majority of children experienced some form of early childhood service before starting school. The most common service was a playgroup although a significant proportion of the children had experienced home‐based care with a relative or family day care provider. The implications of the findings for the development of a policy on early childhood services are discussed.  相似文献   
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This study found that mortality salience in TV news activated more hostile attitude toward the perpetrators and negative judgment on the immigration issue. Social group difference influenced news viewers’ immigration issue judgment, but did not affect their resultant hostility and perceived vulnerability. More negative attitudes emerged toward the immigration issue when immigrant perpetrators were portrayed negatively in the news. News viewers with exposure to mortality salience in TV news reported more negative toward immigrants. Exposure to mortality-related elements in TV news could lead to social conflicts that were viewed as a severe threat by U.S. government and policymakers.  相似文献   
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