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181.
For one‐way fixed effects ANOVA, it is well known that the conventional F test of the equality of means is not robust to unequal variances, and numerous methods have been proposed for dealing with heteroscedasticity. On the basis of extensive empirical evidence of Type I error control and power performance, Welch's procedure is frequently recommended as the major alternative to the ANOVA F test under variance heterogeneity. To enhance its practical usefulness, this paper considers an important aspect of Welch's method in determining the sample size necessary to achieve a given power. Simulation studies are conducted to compare two approximate power functions of Welch's test for their accuracy in sample size calculations over a wide variety of model configurations with heteroscedastic structures. The numerical investigations show that Levy's (1978a) approach is clearly more accurate than the formula of Luh and Guo (2011) for the range of model specifications considered here. Accordingly, computer programs are provided to implement the technique recommended by Levy for power calculation and sample size determination within the context of the one‐way heteroscedastic ANOVA model.  相似文献   
182.
The current research tested the concept of institutional agency (IA) and its implications for laypeople's attribution patterns related to economic behaviors and organizational responsibilities. The term “institutional agency” refers to a set of lay theories about whether or not an organization can have personhood and related mental properties, such as wishes, desires, intents, and responsibility. Through three cross‐cultural studies, we found that people do form certain beliefs about IA which are similar to the legal discourse of institutional responsibility. However, there are significant cultural differences in views of IA, and the concept is more mentally salient for Americans than for Chinese. In Study 1, we distinguished institutional from group agency by showing the cultural differences on attributions in the scenario with “individual vs. group agency” and the scenario with “individual vs. institutional agency.” In Study 2, we again demonstrated the stronger salience of IA for Americans than for Chinese by including the individual, group, and institutional agencies together in one scenario. In Study 3, we further demonstrated that the concept of IA is more salient for Americans by presenting three different agents in separate scenarios. The practical implications of these cultural differences for cross‐cultural understanding and the psychological effects of economic globalization are discussed.  相似文献   
183.
Unlike in English, there are no spaces between printed words in Chinese. In this study, we explored how inserting a space before or after a word affects the processing of that word in Chinese reading. Native Chinese readers' eye movements were monitored as they read sentences with different presentation conditions. The results show that inserting a space after a word facilitates its processing, but inserting a space before a word does not show this effect and inhibits the processing of that word in some cases. Our results are consistent with the prediction of a word segmentation and recognition model in Chinese Li et al., 2009, Cognit. Psychol., 58, 525. Additionally, we found that a space guides the initial landing position on the word: the initial landing position was further away from the space that inserted into the text, whether it was before or after a word.  相似文献   
184.
Families play an important role in the lives of individuals with mental illness. Coping with the strain of shifting roles and multiple challenges of caregiving can have a huge impact. Limited information exists regarding race-related differences in families’ caregiving experiences, their abilities to cope with the mental illness of a loved one, or their interactions with mental health service systems. This study examined race-related differences in the experiences of adults seeking to participate in the National Alliance on Mental Illness Family-to-Family Education Program due to mental illness of a loved one. Participants were 293 White and 107 African American family members who completed measures of problem- and emotion-focused coping, knowledge about mental illness, subjective illness burden, psychological distress, and family functioning. Multiple regression analyses were used to determine race-related differences. African American caregivers reported higher levels of negative caregiving experiences, less knowledge of mental illness, and higher levels of both problem-solving coping and emotion-focused coping, than White caregivers. Mental health programs serving African American families should consider targeting specific strategies to address caregiving challenges, support their use of existing coping mechanisms and support networks, and increase their knowledge of mental illness.  相似文献   
185.
This study investigated 4-year-old children’s knowledge of the structural constraints on ellipsis constructions in Mandarin Chinese, focusing on the structural difference between verb phrase (VP) ellipsis and null object constructions. In Mandarin Chinese, if the antecedent clause of a VP-ellipsis structure contains an adverbial modifier, this adverbial modifier must be recovered at the elided site in the second clause. However, if the antecedent clause of a null object construction contains an adverbial modifier, the reconstruction of this adverbial modifier at the elided site is not necessary. Two experiments were conducted to examine whether young Mandarin-speaking children are sensitive to this structural difference between the two ellipsis constructions. The results show that children exhibited adult-like performance in both experiments. This is evidence that young Mandarin-speaking children have knowledge of the structural difference between VP-ellipsis and null object constructions with regard to adverbial recovery. We interpreted the findings in conjunction with previous research as evidence that children’s knowledge of the structural constraints on ellipsis constructions is innately specified.  相似文献   
186.
腹膜透析是终末期肾脏病的有效替代治疗方法之一。2012年4月,河南省对包括慢性肾衰竭在内的六种疾病的新农合报销比例做出重大调整,腹透患者主要经济花费的透析液报销比例由原来的40%提高至80%。通过研究新农合制度调整前后豫北地区腹膜透析患者的临床资料,报告了制度调整后的患者透析充分性提高,贫血、营养状况较前好转,心血管疾病发生率下降,生存质量改善的现况,论证了老龄、糖尿病、营养不良、心血管疾病、透析不充分、较低的医疗保险支付比例是影响腹膜透析患者预后的重要因素,为腹膜透析患者的预后分析提供了理论依据。  相似文献   
187.
188.
选题是计算机化自适应测验(CAT)测试过程的关键环节,选题策略的目标是要达到较高的测量精度,同时也实现试题曝光率控制及其他测验目标的实现.本文根据选题策略的基本原理和衍生发展,将众多CAT选题策略分为五大选题策略系列:Fisher函数系列、K-LI函数系列、α分层系列、贝叶斯系列、b匹配系列;并根据测验目标(测验精度、试题曝光率控制、内容平衡、多条件约束)对这些选题策略进行了细分,并对CAT选题策略的选择思路进行归纳.  相似文献   
189.
在心理学领域,传统的多指标潜变量的测量模型大都采用反映性建构,各指标反映了潜在构念,构念是各指标的原因.但实际上有些构念应该采用形成性建构,各指标是原因,形成了潜在构念.建构方式的选择不仅要从理论来考虑,还要通过数据特征来决定.研究以公共服务动机(PSM)构念为例,通过公益投资游戏取得投资绩效和满意度效标,验证了先前研究提出的“一阶反映二阶形成”建构模式,并进一步检验了层级性建构方式的优势,有助于PSM理论框架与实证测量的统一.  相似文献   
190.
Research has indicated that highly trait-anxious (HTA) individuals exhibit a specific deficit in filtering threat-related distractors from visual–spatial working memory (WM). Prior demonstrations of impaired inhibition control in HTA individuals have mainly focused on tasks that required the inhibition of prepotent response tendencies. Studies on the suppression of emotionally neutral distractors from WM in trait anxiety have also been minimal. In this article, we present a study on the manifestation of general inefficient filtering of neutral distractors during visual–spatial WM maintenance stages in HTA individuals. Female participants performed a visual–spatial WM task while event-related potentials were recorded. They were made to remember the orientations of red rectangles within half of the screen and to ignore all salient green rectangles. As predicted, no significant main effect of group and no interaction between group and condition were found in the N2pc component, suggesting that group differences did not manifest in the initial process of object individuation. During the subsequent WM maintenance phase, HTA individuals were highly inefficient at filtering the irrelevant items from WM, as reflected not only by parallel late contralateral delay activity (CDA; 450 to 900 ms) amplitudes for the distractor condition and the four red items, but also by a smaller filtering efficiency score in the HTA group than in the low-trait-anxiety group. Extending previous studies, our findings verify a general filtering impairment in HTA individuals for task-irrelevant salient distractors during a WM maintenance phase.  相似文献   
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