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31.
探讨幼儿在准确性线索和共识线索冲突情境下对自然与社会领域知识的选择性信任特点。实验1探究幼儿在线索冲突情境下对自然领域知识的选择性信任,选取88名4~6岁幼儿,采用对物品命名的方法,结果发现4岁幼儿依据共识线索进行信任判断,而5~6岁幼儿依据准确性线索进行信任判断;实验2探究幼儿在线索冲突情境下对社会领域知识的选择性信任,选取94名4-6岁幼儿,采用对人格特质命名的方法,结果发现4岁幼儿依据共识线索进行信任判断,5岁幼儿对两类线索没有做出偏向性选择,6岁幼儿依据准确性线索进行信任判断。实验3采用被试内设计,探讨5岁幼儿对两个领域知识的选择性信任,验证了实验1和实验2的相关结果。结论:在线索冲突情境下幼儿对不同领域知识的选择性信任具有不同的年龄发展特点。  相似文献   
32.
In this paper, we discuss the weakness of current action languages for sensing actions with respect to modeling domains with multi-valued fluents. To address this problem, we propose a language with sensing actions and multi-valued fluents, called AMK, provide a transition function based semantics for the language, and demonstrate its use through several examples from the literature. We then define the entailment relationship between action theories and queries in AMK, denoted by ⊧AMK, and discuss some properties about AMK.  相似文献   
33.
This study investigated the responses of 14 giant pandas (Ailuropoda melanoleuca) to 5 enrichment items (3 manipulable objects, 2 feeding devices) that possess different properties affording varying behavioral opportunities. Enrichment items were quantitatively described by using 12 properties. Pandas displayed no preferences among the 5 enrichment treatments, all of which had similar positive effects on behavioral measures of well-being (behavioral diversity, stereotypy). However, each item promoted a distinct behavioral profile, readily mapped onto the enrichment's properties. These results suggest that it may be important to stimulate behavioral diversity but that specific behaviors or enrichment properties are not required. The unique behavioral topography seen with these enrichments also suggests that providing multiple enrichments with varying properties will maximize overall behavioral diversity.  相似文献   
34.
Twenty-five newborn infants were tested for auditory-oral matching behavior when presented with the consonant sound /m/ and the vowel sound /a/ - a precursor behavior to vocal imitation. Auditory-oral matching behavior by the infant was operationally defined as showing the mouth movement appropriate for producing the model sound just heard (mouth opening for /a/ and mouth clutching for /m/), even when the infant produced no sound herself. With this new dependent measure, the current study is the first to show matching behavior to consonant sounds in newborns: infants showed significantly more instances of mouth opening after /a/ models than after /m/ models, and more instances of mouth clutching after /m/ models than after /a/ models. The results are discussed in the context of theories of active intermodal mapping and innate releasing mechanisms.  相似文献   
35.
A problem with interpretations of differences in mathematic achievement between students from Asian countries and those from the United States is the seemingly implicit assumption of the cultural homogeneity of Asian societies. Researchers rarely measure the effects of variables within cultures that are hypothesized to be related to differences across cultures. In the present study, the authors examined the effects of socioeconomic status (SES) and quality of instruction on Chinese students' (1st, 3rd, and 5th grades) understanding of distance, time, and speed. The results indicated that (a) low SES in China can impede the development of children's mathematical cognition and (b) higher SES does not guarantee better performance. The implication is that the gap in mathematical performance between socioeconomically advantaged and disadvantaged children can be narrowed or even eliminated through instructional practices that focus on the systematic training of children's mathematical thinking.  相似文献   
36.
Rules of thumb for power in multiple regression research abound. Most such rules dictate the necessary sample size, but they are based only upon the number of predictor variables, usually ignoring other critical factors necessary to compute power accurately. Other guides to power in multiple regression typically use approximate rather than precise equations for the underlying distribution; entail complex preparatory computations; require interpolation with tabular presentation formats; run only under software such as Mathmatica or SAS that may not be immediately available to the user; or are sold to the user as parts of power computation packages. In contrast, the program we offer herein is immediately downloadable at no charge, runs under Windows, is interactive, self-explanatory, flexible to fit the user’s own regression problems, and is as accurate as single precision computation ordinarily permits.  相似文献   
37.
Study 1 was conducted to examine the contribution of the joint condition of supervisor close monitoring and the presence of creative coworkers to employees' creativity. In addition to replicating Study 1's results, Study 2 examined (a) the joint condition of supervisor developmental feedback and presence of creative coworkers and (b) whether creative personality moderated the contributions of the 2 joint conditions. Converging results from the 2 field studies demonstrated that when creative coworkers were present, the less supervisors engaged in close monitoring, the more employees exhibited creativity. Study 2 also found that the contribution of this joint condition was stronger for employees with less creative personalities and that when creative coworkers were present, the more supervisors provided developmental feedback, the more employees exhibited creativity.  相似文献   
38.
Serotonin (5-HT) modulates numerous processes in the central nervous system that are relevant to neuropsychiatric function and dysfunction. It exerts significant effects on anxiety, mood, impulsivity, sleep, ingestive behavior, reward systems, and psychosis. Serotonergic dysfunction has been implicated in several psychiatric conditions but efforts to more clearly understand the mechanisms of this influence have been hampered by the complexity of this system at the receptor level. There are at least 14 distinct receptors that mediate the effects of 5-HT as well as several enzymes that control its synthesis and metabolism. Pharmacologic agents that target specific receptors have provided clues regarding the function of these receptors in the human brain. 5-HT is also an important modulator of neural development and several groups have employed a genetic strategy relevant to behavior. Several inactivation mutations of specific 5-HT receptors have been generated producing interesting behavioral phenotypes related to anxiety, depression, drug abuse, psychosis, and cognition. In many cases, knockout mice have been used to confirm what has already been suspected based on pharmacologic studies. In other instances, mutations have demonstrated new functions of serotonergic genes in development and behavior.  相似文献   
39.
The authors investigated whether parents and students are consistent, over grade levels, in the importance they assign to school goals. Elementary and high school students (n = 178) and their parents (n = 130) completed a questionnaire addressing the personal importance of students' school goals, defined in terms of school success. Parent-child consistencies in the rating patterns of school goals over grade levels were more common than were inconsistencies. These developmental consistencies support the position that students' school goals are embedded within the parent-child relationship (J. Youniss, 1980; J. Youniss & J. Smollar, 1985) and are scaffolded within it (J. S. Bruner, 1975; L. S. Vygotsky, 1978). Potential sources of relational and phenotypic influences on school goals are discussed, as is the need for effective friendship management and school performance in high school.  相似文献   
40.
The authors investigate two competing hypotheses about how chronic vividness of imagery interacts with the vividness and salience of information in decision making. Results from four studies, covering a variety of decision domains, indicate that chronic imagery vividness rarely amplifies the effects of vivid and salient information. Imagery vividness may, in fact, attenuate the effects of vivid and salient information. This is because, relative to nonvivid imagers, vivid imagers rely less on information that appears obvious and rely more on information that seems less obvious. This tendency is so robust that vividness of imagery may amplify the effects of vivid information only when this information is the only information available in the decision field. The findings seem to reflect vivid imagers' tendency to totally immerse themselves in a decision problem and scrutinize the available information creatively.  相似文献   
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