关于长尾式差分放大电路静态分析中的一些问题

从长尾式差分放大电路的直流等效电路出发,利用戴文宁定理,分析了电路中基极偏流电阻及信号源内阻对静态工作点的影响.     

Children’s attributions about teachers’ intentions

Hostile attribution bias (HAB) has been shown to predict aggressive behavior, especially toward peers. The current study examined whether HAB is also related to conflict with teachers, an important predictor of academic and social success in school‐aged children. A total of 282 second to fourth grade boys in 74 classrooms completed a self‐report measure of HAB toward teachers, while their teachers assessed conflict in the teacher–student relationship. Results supported the presence of a positive relationship between HAB toward teachers and conflict with teachers. These findings suggest that HAB toward teachers may be an indicator of difficulties and, pending further research, a potential avenue for intervention to improve teacher–student relationships.     

Intergroup Socialization: The Influence of Parents’ Family Communication Patterns on Adult Children’s Racial Prejudice and Tolerance

The purpose of this study was to examine the influence of family communication environments on children’s intergroup socialization. Adult children (n = 200) reported on their parents’ conformity and conversation orientations and their own racial attitudes and intergroup orientations. Results evidenced ingroup bias, social dominance, and identification with parent as mediators of the positive relationship between conformity orientation and racial prejudice and the negative relationship between conformity orientation and racial tolerance. Results also revealed that children from consensual and protective families harbor the most racial prejudice and least racial tolerance. Future directions related to intergroup contact interventions, racially diverse families, and qualitative assessments of parent–child interactions are discussed.     

Smoking, discount rates, and returns to education

Individual time preference determines schooling enrolment. Moreover, smoking behavior in early ages has been shown to be highly related to time preference rates. Insofar as discount rates are uncorrelated to ability, predicting school enrolment by discount rates can get rid of the ability bias in an earnings regression. Accordingly, we use smoking at age 16 as an instrument for schooling. Doing this for Austrian cross-sectional data, we find no evidence of ability bias in a simple earnings regression; the results are more mixed if family background is also included.     

Bias and the limits of pooling for large collections

Modern retrieval test collections are built through a process called pooling in which only a sample of the entire document set is judged for each topic. The idea behind pooling is to find enough relevant documents such that when unjudged documents are assumed to be nonrelevant the resulting judgment set is sufficiently complete and unbiased. Yet a constant-size pool represents an increasingly small percentage of the document set as document sets grow larger, and at some point the assumption of approximately complete judgments must become invalid. This paper shows that the judgment sets produced by traditional pooling when the pools are too small relative to the total document set size can be biased in that they favor relevant documents that contain topic title words. This phenomenon is wholly dependent on the collection size and does not depend on the number of relevant documents for a given topic. We show that the AQUAINT test collection constructed in the recent TREC 2005 workshop exhibits this biased relevance set; it is likely that the test collections based on the much larger GOV2 document set also exhibit the bias. The paper concludes with suggested modifications to traditional pooling and evaluation methodology that may allow very large reusable test collections to be built.

生活背后的力量——从我国的民族分类看多元文化的“和而不同”

当前,倡导文化多元化发展的呼声日趋高涨.鉴于此,结合库恩提出的文化不可通约理论,从民族分类的角度出发探讨如何消除心理偏见对“和而不同”的文化追求的不良影响,以期为我国多民族文化的发展问题做一些反思性的铺垫.     

Attention biases and social-emotional development in preschool-aged children who have been exposed to domestic violence

BackgroundSchool-aged children and adolescents exposed to domestic violence (DV) disproportionality attend to threatening and sad cues in their environment. This bias in attention has been found to predict elevations in symptoms of psychopathology. Studies have yet to explore attention biases using eyetracking technology in preschool-aged children with DV exposure.ObjectiveThis study investigated whether preschool-aged children exposed to DV show vigilance to angry and sad faces versus happy faces and a target non-face stimulus relative to non-exposed children, and whether such vigilance relates to child social-emotional development.Participants and settingPreschool-aged children were recruited from a large, diverse, urban community. DV-exposed children were recruited from a dyadic, mother-child treatment group specifically designed for, and restricted to, mothers who have experienced domestic violence (DV-exposed group, n = 23). Children with no prior exposure to DV and their mothers were recruited within the same community (non-exposed group, n = 32).MethodsChildren completed an eye-tracking task to assess their attention to face stimuli and mothers rated their children's social-emotional development. Total duration of fixations were analyzed.ResultsResults showed that DV-exposed children have a significantly stronger attention bias away from sad faces (p = 0.03; d = 0.62) and neutral faces (p = 0.02; d = 0.70) relative to non-exposed children, and this attention bias away from sad and neutral faces is associated with child social-emotional problems. Contrary to our hypothesis, no bias towards anger was found for DV-exposed versus non-exposed children.ConclusionsThis study contributes to growing evidence that young children's negative attention biases influence functioning and have important implications for children's well-being and development.     

城市偏向与城乡收入差距的实证分析

城市偏向制度使政府在投资取向、财政分配、土地利用和其他政策的制定上均有利于城市,往往在城市和农村之间有着不合理的城市倾斜,导致我国城乡收入差距日益扩大．本文根据1978—2009年的时序数据,对城市偏向与城乡收入差距两者之间进行计量分析．通过建立向量自回归模型（VAR）并进行格兰杰（GRANGER）因果检验等,得出结论...     

Transition from web to mobile payment services: The triple effects of status quo inertia

Drawing from status quo bias theory and coping theory, this study examines how the inertial use of incumbent web payment (WP) services influences users’ intention to use new mobile payment (MP) services. By conducting an online survey (n = 491), this study reveals that inertia demonstrates triple effects on intention to use MP services: direct, bias, and moderating. The direct effect suggests that inertia directly decreases intention to use MP. The bias effect means that inertia leads to biased assessment of perceived value and perceived threat, thereby decreasing intention to use MP. The moderating effect denotes that inertia strengths the relationship between perceived controllability and intention to use MP. We expect that these findings can provide noteworthy insights for the intervention and prevention of inertia in the web-mobile payment transition context.     

Comparison of Self-Reported Sedentary Time on Weekdays with an Objective Measure (activPAL)

ABSTRACT

Self-reports are commonly used tools for obtaining sedentary behaviors. The aim of our study was to assess agreement between two self-reports of sedentary time and a gold standard sedentary time objective monitor. A worksite sample (n = 42) completed the Slovenian version of the Global Physical Activity Questionnaire (GPAQ), the Slovenian version of the Sedentary Behaviour Questionnaire (SBQ for weekdays) and wore an objective physical activity monitor (activPAL) for up to five consecutive working days. Results revealed that GPAQ and SBQ consistently underestimated the total sedentary time, with the mean bias of ?165 min/day and ?181 min/day, respectably. Wide limits of agreement showed poor precision and intraclass correlation revealed a low level of agreement. GPAQ and SBQ are not recommended to be used in studies seeking for relationships with health outcomes, nor in studies where detecting the behavioral change is of interest. Objective measurement should be the preferred choice when possible.