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61.
62.
Knight DM 《Endeavour》2000,24(4):165-169
Humphry Davy (1778–1829) was one of the first professional scientists, earning his living and rising spectacularly from an impoverished upbringing in Cornwall to be President of the Royal Society and a baronet. He owed his rise to patronage as well as to his range of abilities: as a lecturer, as a chemical theorist and as a very early applied scientist. But his exalted position brought him little happiness, for he could not satisfy all the hopes put upon him as the successor to Sir Joseph Banks. Admired rather than loved, he became unpopular and was seen as haughty. In his last two years, spent wandering lonely and sickly in Italy and the Alps, he sought to make sense of his life, writing dialogues as his bequest to the new generation. 相似文献
63.
While there is no universal logic of induction, the probabilitycalculus succeeds as a logic of induction in many contexts throughits use of several notions concerning inductive inference. Theyinclude Addition, through which low probabilities representdisbelief as opposed to ignorance; and Bayes property, whichcommits the calculus to a refute and rescale dynamicsfor incorporating new evidence. These notions are independentand it is urged that they be employed selectively accordingto needs of the problem at hand. It is shown that neither isadapted to inductive inference concerning some indeterministicsystems.
- 1 Introduction
- 2 Failure of demonstrations of universality
- 2.1 Working backwards
- 2.2 The surface logic
- 3 Framework
- 3.1 The properties
- 3.2 Boundaries
- 3.2.1 Universalcomparability
- 3.2.2 Transitivity
- 3.2.3 Monotonicity
- 3.2.2 Transitivity
- 3.2 Boundaries
- 4 Addition
- 4.1 The property: disbelief versus ignorance
- 4.2Boundaries
- 5 Bayes property
- 5.1 The property
- 5.2 Bayes' theorem
- 5.3Boundaries
- 5.3.1 Dogmatism of the priors
- 5.3.2 Impossibilityof prior ignorance
- 5.3.3 Accommodation of virtues
- 5.3.2 Impossibilityof prior ignorance
- 5.2 Bayes' theorem
- 6Real values
- 7 Sufficiency and independence
- 8 Illustrations
- 8.1 All properties retained
- 8.2 Bayes propertyonly retained
- 8.3 Induction without additivity and Bayes property
- 8.2 Bayes propertyonly retained
- 9Conclusion
- 2 Failure of demonstrations of universality
64.
We present a new paradigm for the automatic creation of document headlines that is based on direct transformation of relevant textual information into well-formed textual output. Starting from an input document, we automatically create compact representations of weighted finite sets of strings, called WIDL-expressions, which encode the most important topics in the document. A generic natural language generation engine performs the headline generation task, driven by both statistical knowledge encapsulated in WIDL-expressions (representing topic biases induced by the input document) and statistical knowledge encapsulated in language models (representing biases induced by the target language). Our evaluation shows similar performance in quality with a state-of-the-art, extractive approach to headline generation, and significant improvements in quality over previously proposed solutions to abstractive headline generation. 相似文献
65.
In this paper,we prove that the Veronese surface can be determined by the 1-spectrum of the Laplace operator. 相似文献
66.
The present research examined the role of maladaptive self-regulatory beliefs as vulnerability factors for academic and emotional difficulties during the transition to middle school. A short-term longitudinal design was employed to follow two groups of early adolescents: 187 adolescents who experienced a school transition between the fifth and sixth grades, and 142 adolescents who did not experience a school transition between the fifth and sixth grades. Adolescents completed measures of perceptions of academic control and importance of academic success, experience of chronic academic strain, daily school hassles, and depressive symptoms. Teachers reported on students' academic engagement, including levels of helpless behavior, effort, and academic performance. Consistent with the proposed model of self-regulation, maladaptive self-regulatory beliefs (i.e., decreased perceptions of academic control and importance) predicted individual differences in perceived school-related stress and depressive symptoms over the course of the middle school transition, but were not associated with academic and emotional difficulties in adolescents who remained in a stable school environment. Moreover, a self-regulatory sequence was identified proceeding from maladaptive self-regulatory beliefs, to academic disengagement, to enhanced perceptions of school-related stress, to depressive symptoms. This study bridges prior theory and research concerning the psychological impact of normative developmental transitions, the developmental context of depression, and the associations among self-regulatory beliefs, achievement-related behavior, and emotional experience. 相似文献
67.
OBJECTIVE: A model was examined in which the association between a parent's history of abuse and the parent's own abusive behavior toward his or her children was hypothesized to be mediated by parental psychopathology, early childbearing, and consistency of discipline. Additionally, the effect of severity of abuse on the likelihood of becoming abusive was examined. METHOD: Participants were 109 parents (G1) and their male children (G2) who were involved in a longitudinal study. The G1 parents reported on their own experiences of abuse when they were children. Ten years later, the G2 youths reported on the G1 parents' abusive behavior toward them. A number of other factors, including parental socioeconomic status (SES), antisocial behavior, depression and Post-traumatic Stress Disorder (PTSD), consistency of discipline, and the perceived early difficulty of the G2 children were measured. RESULTS: As reported by their own children, parents who reported having been abused in childhood were significantly more likely to engage in abusive behaviors toward the next generation. Findings indicated that abuse experienced by the parents, as well as consistency of discipline and depression plus PTSD, were predictive of parental abuse of the child. Contrary to hypotheses, the effects were not fully mediated. However, there were significant interactions between parental history of abuse and consistency of discipline, as well as abuse history and depression and PTSD. Parents who had experienced multiple acts of abuse and at least one physical impact were more likely to become abusive than were the other parents. CONCLUSIONS: The implications of these findings for preventive interventions are discussed. 相似文献
68.
69.
Cultural Studies of Science Education - Over the last few decades, there has been an international focus on productive talk in science classrooms, requiring teachers to use more dialogic practices... 相似文献
70.
Joe D. Nichols 《Learning Environments Research》2006,9(2):149-161
This project focused on the goal of establishing a classroom model of motivation in which the source of student motivation is based on internal mechanisms or structures, along with the establishment of greater self-regulatory opportunities for students, and which results in greater student empowerment and motivation. One-hundred current elementary and secondary teachers and 100 university preservice teacher education students completed a 40-item Likert-type questionnaire that focused on four classroom dimensions of affirmation, rejection, student empowerment and teacher control. The results of this project suggested that, although veteran and preservice teachers agreed on the need for teacher control in the classroom, there was less agreement about their perceptions of the need to create a classroom environment of positive affirmation and student empowerment. Implications for future research and the need for creating an affirming, empowering, motivational classroom environment are discussed in light of the limitations for teachers and schools to encourage these constructs associated with recent federal legislative policies. 相似文献