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61.
An interesting case of the complex interaction between theory and experiment can be found in many experiments in quantum physics employing classical reasoning. It is expected that this practice would lead to quantitative inaccuracy, unless the measurements’ results were averaged. Whether or not this inaccuracy is significant depends critically on the details of the particular experimental situation. The example of Millikan's photoelectric experiment, in which he obtained a precise value of Planck's constant, provides a good case for illustrating the process of estimating the inaccuracy resulting from the classical‐quantum discrepancy. In the case of Millikan's experiment, it seems that a significant inaccuracy was avoided because of fortunate coincidences. In general, in the absence of a careful analysis, it is impossible to say whether the use of classical reasoning interferes with the accuracy of a quantum‐physical experiment.  相似文献   
62.
A rodent model of diencephalic amnesia, pyrithiamine-induced thiamine deficiency (PTD), was used to investigate diencephalic-hippocampal interactions. Acetylcholine (ACh) release, a marker of memory-related activation, was measured in the hippocampus of PTD-treated and control rats prior to, during, and after spontaneous alternation test. During behavioral testing, all animals displayed increases in ACh release. However, both the percent increase of ACh release during spontaneous alternation testing and the alternation scores were higher in control rats relative to PTD-treated rats. Thus, when rats are tested on a task with demands dependent on the hippocampus, it appears that the hippocampus is not fully activated after diencephalic damage.  相似文献   
63.
This paper uses an extension of the network algorithm originally introduced by Mehta and Patel to construct exact tail probabilities for testing the general hypothesis that item responses are distributed according to the Rasch model. By assuming that item difficulties are known, the algorithm is applicable to the statistical tests either given the maximum likelihood ability estimate or conditioned on the total score. A simulation study indicates that the network algorithm is an efficient tool for computing the significance level of a person fit statistic based on test lengths of 30 items or less.  相似文献   
64.
It has long been part of the item response theory (IRT) folklore that under the usual empirical Bayes unidimensional IRT modeling approach, the posterior distribution of examinee ability given test response is approximately normal for a long test. Under very general and nonrestrictive nonparametric assumptions, we make this claim rigorous for a broad class of latent models.This research was partially supported by Office of Naval Research Cognitive and Neural Sciences Grant N0014-J-90-1940, 442-1548, National Science Foundation Mathematics Grant NSF-DMS-91-01436, and the National Center for Supercomputing Applications. We wish to thank Kumar Joag-dev and Zhiliang Ying for enlightening suggestions concerning the proof of the basic result.The authors wish to thank Kumar Joag-Dev, Brian Junker, Bert Green, Paul Holland, Robert Mislevy, and especially Zhiliang Ying for their useful comments and discussions.  相似文献   
65.
The current study tested the ability of whines and child-directed speech to attract the attention of listeners involved in a story repetition task. Twenty non-parents and 17 parents were presented with two dull stories, each playing to a separate ear, and asked to repeat one of the stories verbatim. The story that participants were instructed to ignore was interrupted occasionally with the reader whining and using child-directed speech. While repeating the passage, participants were monitored for Galvanic skin response, heart rate, and blood pressure. Based on 4 measures, participants tuned in more to whining, and to a lesser extent child-directed speech, than neutral speech segments that served as a control. Participants, regardless of gender or parental status, made more mistakes when presented with the whine or child-directed speech, they recalled hearing those vocalizations, they recognized more words from the whining segment than the neutral control segment, and they exhibited higher Galvanic skin response during the presence of whines and child- directed speech than neutral speech segments. Whines and child-directed speech appear to be integral members of a suite of vocalizations designed to get the attention of attachment partners by playing to an auditory sensitivity among humans. Whines in particular may serve the function of eliciting care at a time when caregivers switch from primarily mothers to greater care from other caregivers.  相似文献   
66.
There is a relatively consistent negative relationship between adolescent depressive symptoms and educational achievement (e.g., grade point average [GPA]). However, the causal direction for this association is less certain due to the lack of longitudinal data with both indicators measured across at least 2 time periods and due to the lack of application of more sophisticated contemporary statistical techniques. We present multivariate results from a large longitudinal cohort-sequential study of high school students (N = 7,317) with measures of self-reported depressive symptoms and self-reported GPAs across multiple time points (following McArdle, 2009, and McArdle, Johnson, Hishinuma, Miyamoto, & Andrade, 2001) using an ethnically diverse sample from Hawai'i. Contemporary statistical techniques included bivariate dynamic structural equation modeling (DSEM), multigroup ethnic and gender DSEMs, ordinal scale measurement of key outcomes, and imputation for incomplete longitudinal data. The findings suggest that depressive symptoms affect subsequent academic achievement and not the other way around, especially for Native Hawaiians compared with female non-Hawaiians. We further discuss the scientific, applied, and methodological-statistical implications of the results, including the need for further theorizing and research on mediating variables. We also discuss the need for increased prevention, early intervention, screening, identification, and treatment of depressive symptoms and disorders. Finally, we argue for utilization of more contemporary methodological-statistical techniques, especially when violating parametric test assumptions.  相似文献   
67.
The aims of this article are (1) to propose a modified theory of consumption values (MTCV) for investigation of online gamer perceptions of the value of purchasable game items and (2) to apply the developed MTCV to multiple game genres and player age groups. To address these aims, 327 valid questionnaires were obtained and analyzed. The original theory of consumption values (TCV) was modified to apply to the specific characteristics of online games. The original TCV specifies five types of consumption values: functional value, social value, emotional value, conditional value, and epistemic value. After revising the TCV to apply to the examination of online games, we proposed that the MTCV be composed of character competency value, enjoyment value, visual authority value, and monetary value. The validity of the MTCV was proven by statistically analyzing the responses provided by the 327 valid questionnaires. To examine the second aim, experiments were conducted to examine the MTCV in three online game genres-massive multiplayer online role-playing games, first-person shooters games, and casual games. The second aim was also studied via questionnaires that examined the ages of online gamers. It was determined that massive multiplayer online role-playing games players regard visual authority value and monetary value as more important than do casual gamers. It was also determined that younger gamers tend to be more interested in visual authority, whereas older gamers tend to be more interested in character competency. This research provides a foundation for future studies to extend the MTCV to consider other user factors, such as cultural effects.  相似文献   
68.
The purpose of the current study was to examine the criterion validity of the Borderline Personality Features Scale for Children (BPFS-C) by assessing the performance of the self-report and a newly developed parent report version of the measure (BPFS-P) in detecting a borderline personality disorder (BPD) diagnosis in adolescent inpatients. This study also examined parent-child agreement and the internal consistency of the BPFS subscales. An inpatient sample of adolescents (n = 51) ranging from ages 12-18 completed the BPFS and were administered the Child Interview for DSM-IV Borderline Personality Disorder (CI-BPD) by trained clinical research staff. ROC analyses revealed that the BPFS-C has high accuracy (AUC = .931; Se = .856; Sp = .840) in discriminating adolescents with a diagnosis of BPD, as measured by the CI-BPD, while the BPFS-P has moderate accuracy (AUC = .795; Se = .733; Sp = .720). Parent-child agreement on total scores was significant (r = .687; p < .005). Cronbach's alphas suggested internal consistency for the four subscales of the BPFS. These findings support the criterion validity of this measure, particularly the self-report version, in adolescent inpatient settings.  相似文献   
69.
The Implicit Association Test (IAT) is the most widely used indirect measure of attitudes in social psychology. It has been suggested that artefacts such as salience asymmetries and familiarity can influence performance on the IAT. Chang and Mitchell (2009) proposed that the ease with which IAT stimuli are classified (classification fluency) is the common mechanism underlying both of these factors. In the current study, we investigated the effect of classification fluency on the IAT and trialled a measure-the split IAT-for dissociating between the effects of valence and salience in the IAT. Across six experiments, we examined the relationship between target classification fluency and salience asymmetries in the IAT. In the standard IAT, the more fluently classified target category was, all else being equal, compatible with pleasant attributes over unpleasant attributes. Furthermore, the more fluently classified target category was more easily classified with the more salient attribute category in the split IAT, independent of evaluative associations. This suggests that the more fluently classified category is also the more salient target category.  相似文献   
70.
This study examined relations of achievement goals of writers who are speakers of English as a foreign language (EFL), the frequency of their writing strategy use, and the quality of their writing from a multiple goals perspective. The goal profiles of 57 EFL college students with similar writing proficiency were based on rating items of an unpublished scale; Group 1 had strong mastery and strong performance-approach goals, and two groups included students with only one strong mastery (Group 2) or performance (Group 3) goal. Think-aloud protocols indicated that the participants adopted 21 strategies in an argumentative writing task, classified into five categories. Group 1 was found to use writing strategies of monitoring or evaluating, revising, and compensating significantly more often than the other two groups, and produced better essays. Strong mastery and performance-approach goals might be beneficial for EFL college writers.  相似文献   
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