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51.
Three experiments explored the semantics of the mass-count distinction in young children and adults. In Experiments 1 and 2, the quantity judgments of participants provided evidence that some mass nouns refer to individuals, as such. Participants judged one large portion of stuff to be "more" than three tiny portions for substance-mass nouns (e.g. mustard, ketchup), but chose according to number for count nouns (e.g. shoes, candles) and object-mass nouns (e.g. furniture, jewelry). These results suggest that some mass nouns quantify over individuals, and that therefore reference to individuals does not distinguish count nouns from mass nouns. Thus, Experiments 1 and 2 failed to support the hypothesis that there exist one-to-one mappings between mass-count syntax and semantics for either adults or young children. In Experiment 3, it was found that for mass-count flexible terms (e.g. string, stone) participants based quantity judgments on number when the terms were used with count syntax, but on total amount of stuff when used with mass syntax. Apparently, the presence of discrete physical objects in a scene (e.g. stones) is not sufficient to permit quantity judgments based on number. It is proposed that object-mass nouns (e.g. furniture) can be used to refer to individuals due to lexically specified grammatical features that normally occur in count syntax. Also, we suggest that children learning language parse words that refer to individuals as count nouns unless given morpho-syntactic and referential evidence to the contrary, in which case object-mass nouns are acquired. 相似文献
52.
Two new tests for a model for the response times on pure speed tests by Rasch (1960) are proposed. The model is based on the
assumption that the test response times are approximately gamma distributed, with known index parameters and unknown rate
parameters. The rate parameters are decomposed in a subject ability parameter and a test difficulty parameter. By treating
the ability as a gamma distributed random variable, maximum marginal likelihood (MML) estimators for the test difficulty parameters
and the parameters of the ability distribution are easily derived. Also the model tests proposed here pertain to the framework
of MML. Two tests or modification indices are proposed. The first one is focused on the assumption of local stochastic independence,
the second one on the assumption of the test characteristic functions. The tests are based on Lagrange multiplier statistics,
and can therefore be computed using the parameter estimates under the null model. Therefore, model violations for all items
and pairs of items can be assessed as a by-product of one single estimation run. Power studies and applications to real data
are included as numerical examples. 相似文献
53.
On Some Varieties of MTL-algebras 总被引:1,自引:0,他引:1
54.
Fripp D Owen C Quintana-Rizzo E Shapiro A Buckstaff K Jankowski K Wells R Tyack P 《Animal cognition》2005,8(1):17-26
Bottlenose dolphins are unusual among non-human mammals in their ability to learn new sounds. This study investigates the importance of vocal learning in the development of dolphin signature whistles and the influence of social interactions on that process. We used focal animal behavioral follows to observe six calves in Sarasota Bay, Fla., recording their social associations during their first summer, and their signature whistles during their second. The signature whistles of five calves were determined. Using dynamic time warping (DTW) of frequency contours, the calves signature whistles were compared to the signature whistles of several sets of dolphins: their own associates, the other calves associates, Tampa Bay dolphins, and captive dolphins. Whistles were considered similar if their DTW similarity score was greater than those of 95% of the whistle comparisons. Association was defined primarily in terms of time within 50 m of the mother/calf pair. On average, there were six dolphins with signature whistles similar to the signature whistles of each of the calves. These were significantly more likely to be Sarasota Bay resident dolphins than non-Sarasota dolphins, and (though not significantly) more likely to be dolphins that were within 50 m of the mother and calf less than 5% of the time. These results suggest that calves may model their signature whistles on the signature whistles of members of their community, possibly community members with whom they associate only rarely. 相似文献
55.
人口逆淘汰及其预防 总被引:2,自引:0,他引:2
冯泽永 《医学与哲学(人文社会医学版)》2004,25(2):62-64
对人口逆淘汰必须全面、动态地加以认识.必须阻止人口逆淘汰,提高人口质量,变"人口"为"人力".教育是关键措施,医疗卫生和环境改善十分重要,但决不能鼓励高学历人口多生育而限制农村人口的出生. 相似文献
56.
By regarding the latent random vectors as hypothetical missing data and based on the conditional expectation of the complete-data
log-likelihood function in the EM algorithm, we investigate assessment of local influence of various perturbation schemes
in a nonlinear structural equation model. The basic building blocks of local influence analysis are computed via observations
of the latent variables generated by the Metropolis-Hastings algorithm, while the diagnostic measures are obtained via the
conformal normal curvature. Seven perturbation schemes, including some perturbation schemes on latent vectors, are investigated.
The proposed procedure is illustrated by a simulation study and a real example.
Acknowledgment: This research is fully supported by a grant (CUHK 4243/02H) from the Research Grant Council of the Hong Kong
Special Administration Region. The authors are indebted to ICPSR and the relevant funding agency for allowing use of their
data, and to the Editor and reviewers for their valuable comments for improving the paper. 相似文献
57.
The influence of hierarchy on probability judgment 总被引:6,自引:0,他引:6
Consider the task of predicting which soccer team will win the next World Cup. The bookmakers may judge Brazil to be the team most likely to win, but also judge it most likely that a European rather than a Latin American team will win. This is an example of a non-aligned hierarchy structure: the most probable event at the subordinate level (Brazil wins) appears to be inconsistent with the most probable event at the superordinate level (a European team wins). In this paper we exploit such structures to investigate how people make predictions based on uncertain hierarchical knowledge. We distinguish between aligned and non-aligned environments, and conjecture that people assume alignment. Participants were exposed to a non-aligned training set in which the most probable superordinate category predicted one outcome, whereas the most probable subordinate category predicted a different outcome. In the test phase participants allowed their initial probability judgments about category membership to shift their final ratings of the probability of the outcome, even though all judgments were made on the basis of the same statistical data. In effect people were primed to focus on the most likely path in an inference tree, and neglect alternative paths. These results highlight the importance of the level at which statistical data are represented, and suggest that when faced with hierarchical inference problems people adopt a simplifying heuristic that assumes alignment. 相似文献
58.
It is well-known that the representations of the Thurstonian models for difference judgment data are not unique. It has been shown that equivalence classes can be formed to provide a more meaningful partition of the covariance structures of the Thurstonian ranking models. In this paper, we examine the equivalence relations between Thurstonian covariance structure models for paired comparison data obtained under multiple judgment and discuss their implications on the general identification constraints and methods to check for parameter identifiability in restricted models.The author is indebted to Ulf Böckenholt and Albert Maydeu-Olivares for their significant comments and suggestions which led to considerable improvement in this article. 相似文献
59.
《孔丛子》六卷当出自“汉魏孔氏家学” ,其前三卷记孔子、子思言行 ,可能是辑先秦孔氏遗文。《孔丛子·记义》篇载有一大段孔子对《诗》的评论 ,其与上博简《孔子诗论》有着内在的关系 ,可以将它们视为同一个体系而相互参释和补充。《孔丛子》“诗论”与上博简《诗论》都反映了先秦儒家早期说诗的风格和内容 ,而与汉代形成的《诗序》传统不同。《孔丛子》“诗论”对朱熹的《诗经集传》有一定影响 ,在从汉代诗学向宋代诗学的转变过程中起了一定的作用。 相似文献
60.
The papers in this special issue of Clinical Child and Family Psychology Review provided an overview of what is known about children's exposure to domestic violence, and include indications of gaps in extant research. These gaps and research needs are summarized in this conclusion. Specifically, there is need for further research in several broad areas: definition and measurement of children's exposure to domestic violence; development of research methods and statistical designs that provide detailed information and provide for evidence of intervention effectiveness; impact of domestic violence on parenting and family functioning; the role of child factors and exposure to violence factors in predicting developmental risk and resilience; medical and health consequences of exposure to violence; and the nature of child-system interaction in response to domestic violence. Research needs in these areas are discussed in greater detail, and specific questions are raised for further development. 相似文献