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101.
缺失值是社会科学研究中非常普遍的现象。全息极大似然估计和多重插补是目前处理缺失值最有效的方法。计划缺失设计利用特殊的实验设计有意产生缺失值, 再用现代的缺失值处理方法来完成统计分析, 获得无偏的统计结果。计划缺失设计可用于横断面调查减少(或增加)问卷长度和纵向调查减少测量次数, 也可用于提高测量有效性。常用的计划缺失设计有三式设计和两种方法测量。  相似文献   
102.
Although theoretical results for several algorithms in many application domains were presented during the last decades, not all algorithms can be analyzed fully theoretically. Experimentation is necessary. The analysis of algorithms should follow the same principles and standards of other empirical sciences. This article focuses on stochastic search algorithms, such as evolutionary algorithms or particle swarm optimization. Stochastic search algorithms tackle hard real-world optimization problems, e.g., problems from chemical engineering, airfoil optimization, or bio-informatics, where classical methods from mathematical optimization fail. Nowadays statistical tools that are able to cope with problems like small sample sizes, non-normal distributions, noisy results, etc. are developed for the analysis of algorithms. Although there are adequate tools to discuss the statistical significance of experimental data, statistical significance is not scientifically meaningful per se. It is necessary to bridge the gap between the statistical significance of an experimental result and its scientific meaning. We will propose some ideas on how to accomplish this task based on Mayo’s learning model (NPT*).  相似文献   
103.
We consider the problems arising from using sequences of experiments to discover the causal structure among a set of variables, none of whom are known ahead of time to be an “outcome”. In particular, we present various approaches to resolve conflicts in the experimental results arising from sampling variability in the experiments. We provide a sufficient condition that allows for pooling of data from experiments with different joint distributions over the variables. Satisfaction of the condition allows for an independence test with greater sample size that may resolve some of the conflicts in the experimental results. The pooling condition has its own problems, but should—due to its generality—be informative to techniques for meta-analysis.  相似文献   
104.
We explore the immediate and longer term consequences of different types of instruction about a central topic in middle school science: the “Control of Variables Strategy” (CVS). CVS represents the procedural and conceptual basis for designing simple, unconfounded experiments, such that unambiguous causal inferences can be made. CVS appears to be what has been called a “developmentally-secondary” process, because even though infants and pre-schoolers can make simple causal inferences from data, middle school children do poorly at CVS unless they receive instruction on this important topic in the science curriculum. In this study, 72 third, fourth, and fifth-grade students were taught CVS via two instructional methods located at extreme points on the direct-to-discovery spectrum with respect to the amount of guidance, information, support, teacher control, and feedback provided during training. Our design included near- and far-transfer measures (at 1 week, 3 months and 3 years). There were two primary outcomes, both of which replicated and partially extended earlier work by Klahr and Nigam (2004) [Klahr, D., & Nigam, M. (2004). The equivalence of learning paths in early science instruction: Effects of direct instruction and discovery learning. Psychological Science, 15, 661–667] First, at each of the three grade levels, many more children learned CVS in the explicit condition than in the exploration condition. Second, but equally important, what students learned was a better predictor of far transfer than the way that they learned.  相似文献   
105.
John Symons 《Axiomathes》2008,18(1):67-89
Intuition serves a variety of roles in contemporary philosophy. This paper provides a historical discussion of the revival of intuition in the 1970s, untangling some of the ways that intuition has been used and offering some suggestions concerning its proper place in philosophical investigation. Contrary to some interpretations of the results of experimental philosophy, it is argued that generalized skepticism with respect to intuition is unwarranted. Intuition can continue to play an important role as part of a methodologically conservative stance towards philosophical investigation. I argue that methodological conservatism should be sharply distinguished from the process of evaluating individual propositions. Nevertheless, intuition is not always a reliable guide to truth and experimental philosophy can serve a vital ameliorative role in determining the scope and limits of our intuitive competence with respect to various areas of inquiry.
John SymonsEmail:
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106.
Recent and puzzling experimental results suggest that people’s judgments as to whether or not an action was performed intentionally are sensitive to moral considerations. In this paper, we outline these results and evaluate two accounts which purport to explain them. We then describe a recent experiment that allegedly vindicates one of these accounts and present our own findings to show that it fails to do so. Finally, we present additional data suggesting no such vindication could be in the offing and that, in fact, both accounts fail to explain the initial, puzzling results they were purported to explain.
Hagop SarkissianEmail:
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107.
108.
The order in which information is received alters the evaluation of causal hypotheses. Specifically, research suggests that the last piece of information oftentimes has the greatest impact on the evaluation and that the difference in subjective value between two pieces of information is an important factor influencing the magnitude of this recency effect. The present paper extends this line of work by exploring individual differences in this phenomenon via one's degree of handedness. Two hundred and five participants were given two hypothetical scenarios and related causal hypotheses accompanied by two pieces of additional information and asked to revise their belief in each hypothesis as information accumulated. Results confirmed predictions that 1) inconsistent/mixed-handers (those who use their non-dominant hand for at least some activities) show a larger effect with two pieces of inconsistent weak or strong information, and 2) neither mixed-handers nor consistent/strong-handers (those who use their dominant hand for almost all activities) show an effect with strong and weak pieces of consistent information. Mixed-handers' susceptibility to persuasive arguments and Ramachandran’s (1995; Ramachandran and Blakeslee, 1998) belief-updating theory centered around communication between the two halves of the brain and functional access to the right hemisphere are used to account for these data.  相似文献   
109.
Recent studies have demonstrated that establishing figure–ground organization influences other perceptual processes. Specifically, figures undergo perceptual processing earlier than ground regions (Lester, Hecht, & Vecera, 2009), and they are processed for longer durations relative to ground regions (Hecht & Vecera, 2011). One potential consequence of figures' extended processing is degraded temporal resolution compared to ground regions. To test this hypothesis, observers completed a modified flicker-fusion task while viewing either displays that contained well-defined figures and grounds or displays that were ambiguous. As evidenced by increased sensitivity for flickering targets on the ground regions, the current results support the claim that figures have poorer temporal resolution than ground regions.  相似文献   
110.
In the present study, we manipulated different types of information available in the parafovea during the reading of Chinese sentences and examined how native Korean readers who learned Chinese as a second language make use of the parafoveal information. Results clearly indicate that, only identical and orthographically similar previews facilitated processing of the target words when they were subsequently fixated. More critically, more parafoveal information was obtained by subjects with higher reading proficiency. These results suggest that, mainly low-level features of the parafoveal words are obtained by the non-native Chinese readers and less attentional resources are available for the readers with lower reading proficiency, thereby causing a reduction of the perceptual span.  相似文献   
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