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931.
Adam Trybus 《逻辑史和逻辑哲学》2013,34(4):329-352
‘The Principles of the Pure Type Theory’ is a translation of Leon Chwistek's 1922 paper ‘Zasady czystej teorii typów’. It summarizes Chwistek's results from a series of studies of the logic of Whitehead and Russell's Principia Mathematica which were published between 1912 and 1924. Chwistek's main argument involves a criticism of the axiom of reducibility. Moreover, ‘The Principles of the Pure Type Theory’ is a source for Chwistek's views on an issue in Whitehead and Russell's ‘no-class theory of classes’ involving the notion of ‘scope’. 相似文献
932.
A key challenge for cognitive psychology is the investigation of mental representations, such as object categories, subjective probabilities, choice utilities, and memory traces. In many cases, these representations can be expressed as a non-negative function defined over a set of objects. We present a behavioral method for estimating these functions. Our approach uses people as components of a Markov chain Monte Carlo (MCMC) algorithm, a sophisticated sampling method originally developed in statistical physics. Experiments 1 and 2 verified the MCMC method by training participants on various category structures and then recovering those structures. Experiment 3 demonstrated that the MCMC method can be used estimate the structures of the real-world animal shape categories of giraffes, horses, dogs, and cats. Experiment 4 combined the MCMC method with multidimensional scaling to demonstrate how different accounts of the structure of categories, such as prototype and exemplar models, can be tested, producing samples from the categories of apples, oranges, and grapes. 相似文献
933.
Previous studies have demonstrated reductions in episodic memory during nicotine withdrawal. However, these studies have been unable to dissociate memory reductions from losses in attention associated with tobacco abstinence. In the present study, the authors sought to determine whether episodic memory reduction is a primary effect of nicotine withdrawal during tobacco abstinence. Heavy smokers were tested when smoking normally and following 24 hrs of abstinence. Participants were tested with a recognition memory task in which items were studied under full and divided attention conditions. Forward digit span and backward digit span were also included as control measures. Withdrawal was associated with a reduction in memory performance that was independent of attention at encoding. The authors conclude that impairment of episodic memory is a primary effect of nicotine withdrawal during tobacco abstinence. Further research is required to determine if this is associated with continued use of tobacco and cessation failures. 相似文献
934.
935.
Adam Kolany 《Studia Logica》2010,95(3):407-416
In the following we show that general property S considered by Cowen [1], Cowen and Kolany in [3] and earlier by Cowen in [2] and Kolany in [4] as hypergraph satisfiability,
can be constructively reduced to (3, 2) · SAT, that is to satisfiability of (at most) triples with two-element forbidden sets. This is an analogue of the“classical” result
on the reduction of SAT to 3 · SAT. 相似文献
936.
Chad?Ebesutani Adam?Bernstein Brad?J.?Nakamura Bruce?F.?Chorpita John?R.?Weisz The Research Network on Youth Mental Health 《Journal of abnormal child psychology》2010,38(2):249-260
The Revised Child Anxiety and Depression Scale—Parent Version (RCADS-P) is a 47-item parent-report questionnaire of youth
anxiety and depression, with scales corresponding to the DSM-IV categories of Separation Anxiety Disorder, Social Phobia,
Generalized Anxiety Disorder (GAD), Panic Disorder, Obsessive-Compulsive Disorder, and Major Depressive Disorder (MDD). The
RCADS-P is currently the only parent-report questionnaire that concurrently assesses youth symptomatology of individual anxiety
disorders as well as depression in accordance with DSM-IV nosology. The present study examined the psychometric properties of the RCADS-P in a large (N = 490), clinic-referred sample of youths. The RCADS-P demonstrated favorable psychometric properties, including high internal
consistency, convergent/divergent validity, as well as strong discriminant validity—evidencing an ability to discriminate
between anxiety and depressive disorders, as well as between the targeted anxiety disorders. Support for the DSM-related six-factor
RCADS-P structure was also evidenced. This structure demonstrated superior fit to a recently suggested alternative to the
DSM-IV classification of anxiety and affective disorders—namely, the MDD/GAD “distress” factor. 相似文献
937.
938.
Using longitudinal and experience sampling designs, the consistency and composition, and personality and motivational predictors,
of the desired affective state are explored. Findings indicate that, while the desired affect is relatively malleable throughout
one semester, it is relatively stable throughout 1 week. Personality and motivations/goals were related to the content of
the desired affective state. Extraversion, neuroticism, agreeableness, and conscientiousness were related to the content of
the desired affective state. In addition, higher-order goals predicted the content of the desired affective state. Our results
suggest that the content of the desired affective state may be largely dependent on personality, motivation, and, potentially,
an interaction between personality and motivation. 相似文献
939.
940.
We study gender differences and the effects of adult’s gender, an authority gap, and an age gap on university students’ perceptions of adult-teen sexual relationships. We specifically examine: the adult’s criminality, damage to the teen’s reputation, and emotional damage to the teen. We use a sample of 2,871 students from a Southwestern university in the U.S. who judged vignettes describing an adult-teen encounter. OLS regression demonstrated that women judged the scenarios more negatively than men. Further analyses found relationships between the experimental variables and each dependent variable and interactions by respondent’s gender and among the experimental variables. Results demonstrate a sexual double standard and highlight respondent’s gender, the age gap, and the authority context for perceptions of adult-teen relationships. 相似文献