Discreteness Causes Bias in Percentage-Based Comparisons: A Case Study From Educational Testing

Discretizing continuous distributions can lead to bias in parameter estimates. We present a case study from educational testing that illustrates dramatic consequences of discreteness when discretizing partitions differ across distributions. The percentage of test takers who score above a certain cutoff score (percent above cutoff, or “PAC”) often describes overall performance on a test. Year-over-year changes in PAC, or ΔPAC, have gained prominence under recent U.S. education policies, with public schools facing sanctions if they fail to meet PAC targets. In this article, we describe how test score distributions act as continuous distributions that are discretized inconsistently over time. We show that this can propagate considerable bias to PAC trends, where positive ΔPACs appear negative, and vice versa, for a substantial number of actual tests. A simple model shows that this bias applies to any comparison of PAC statistics in which values for one distribution are discretized differently from values for the other.     

Penalties and payoffs: The short-term economic consequences of human capital acquisition for resettled refugees in the United States

The relationship between refugee investments in human capital and short-run economic outcomes may influence the extent to which refugees invest in human capital that is associated with positive future economic mobility. Using data from the Annual Survey of Refugees from 2016 and 2017 we assess the relationship between recent investments in human capital and hourly wages for employed refugees in the United States. Results suggest that recent job training has a positive effect on hourly wages. In contrast, enrollment in English classes and educational programmes have no short-term positive effects on hourly wages. When combined with the pressure resettled refugees experience to find employment quickly, these results suggest that the lack of short-term wage benefits from English language or educational courses may dissuade refugees from sufficiently investing in the amount of English language or education necessary to promote positive long-term economic mobility.     

Conditional correlation in asset return and GARCH intensity model

In an asset return series, there is a conditional asymmetric dependence between current return and past volatility depending on the current return’s sign. To take into account the conditional asymmetry, we introduce new models for asset return dynamics in which frequencies of the up and down movements of asset price have conditionally independent Poisson distributions with stochastic intensities. The intensities are assumed to be stochastic recurrence equations of the GARCH type to capture the volatility clustering and the leverage effect. We provide an important linkage between our model and existing GARCH, explain how to apply maximum likelihood estimation to determine the parameters in the intensity model and show empirical results with the S&P 500 index return series.     

A Time-Lag Analysis of the Relationships Among PISA Scores,Scientific Research Publication,and Economic Performance

Due to the poor performance of US students in international math and science tests, many authors worry that the US lead in science is in jeopardy. A recent study by Chen and Luoh (Soc Indic Res 96: 133–143, 2010) challenged this pessimistic view by delinking test performance and labor force quality. It was found that measures such as researchers per capita or scientific journal articles per capita can better account for economic performance. Because it takes time for education and R&;D to yield returns, this project replicated the preceding study using a time-lag structure. Although the results partly concur with previous findings, it is important to point out that GDP might depend on multiple variables acting together. Instead of solely focusing on reforming STEM education as partly measured by international test scores, improving the R&;D infrastructure and openness in trade could also be crucial to the future of the economy.     

Prediction of accrual closure date in multi-center clinical trials with discrete-time Poisson process models

In a phase III multi‐center cancer clinical trial or a large public health study, sample size is predetermined to achieve desired power, and study participants are enrolled from tens or hundreds of participating institutions. As the accrual is closing to the target size, the coordinating data center needs to project the accrual closure date on the basis of the observed accrual pattern and notify the participating sites several weeks in advance. In the past, projections were simply based on some crude assessment, and conservative measures were incorporated in order to achieve the target accrual size. This approach often resulted in excessive accrual size and subsequently unnecessary financial burden on the study sponsors. Here we proposed a discrete‐time Poisson process‐based method to estimate the accrual rate at time of projection and subsequently the trial closure date. To ensure that target size would be reached with high confidence, we also proposed a conservative method for the closure date projection. The proposed method was illustrated through the analysis of the accrual data of the National Surgical Adjuvant Breast and Bowel Project trial B‐38. The results showed that application of the proposed method could help to save considerable amount of expenditure in patient management without compromising the accrual goal in multi‐center clinical trials. Copyright © 2012 John Wiley & Sons, Ltd.     

Examining the Quality of Adolescent–Parent Relationships Among Chilean Families

The purpose of this study was to examine if adolescents’ reports of warm and harsh parenting practices by their mothers and fathers varied as a function of demographic, youth and their mothers or mother figures’ individual and family characteristics. Data are from 707 community-dwelling adolescents (mean age = 14, SD = 1.4) and their mothers or mother figures in Santiago, Chile. Having a warmer relationship with both parents was inversely associated with the adolescents’ age and positively associated with adolescents’ family involvement and parental monitoring. Both mothers’ and fathers’ harsh parenting were positively associated with adolescent externalizing behaviors and being male and inversely associated with youth autonomy and family involvement. These findings suggest that net of adolescent developmental emancipation and adolescent behavioral problems, positive relationships with parents, especially fathers, may be nurtured through parental monitoring and creation of an interactive family environment, and can help to foster positive developmental outcomes.     

“Female Virginity Complex” Untied: Young Chinese Women's Experience of Virginity Loss and Sexual Coercion

This article selects the critical moment of virginity loss in young Beijing women's lives to look at the meaning of sexual coercion in dating relationships. The authors observed that many young Chinese women presented their first experience of sex as containing some elements of sexual coercion that were being described as “minor,” do not involve obvious physical force, but are unpleasant and regretful experiences of virginity loss. This article contributes to a new understanding of virginity loss and sexual coercion in China and sheds light on the social transformation of sexuality from the Maoist era to the postsocialist era. Implications for social work practice and research in China are also discussed.     

Everyday health communication experiences of college students

OBJECTIVE: The authors examined college students' day-to-day health communication experiences. PARTICIPANTS: A convenience sample of 109 midwestern university students participated in the study. METHODS: The participants completed health communication diaries for 2 weeks, generating 2,185 records. Frequent health topics included nutrition and diet, minor health concerns, risky health practices, and body fitness. RESULTS: Approximately 27% of health communication experiences involved the proactive seeking of health-related information or advice. Interpersonal venues (face-to-face, telephone, and e-mail) were evident in about 75% of the records, which were dominated by exchanges with friends and family members. The authors found modest interactions of topic, channel, and purpose. CONCLUSIONS: Congruent with the uses and gratifications theory, the authors found that satisfaction with and perceived impact of health communication experiences varied by topic, channel, relationship, and purpose.     

What Makes Koreans Happy?: Exploration on the Structure of Happy Life among Korean Adults

The current study explored the perceptions of Korean people about what can make them happy and constructed a comprehensive measurement of happiness of Korean. A total of 61 Korean adults participated in Focused Group Interview (FGI), where they were asked three questions (e.g., What makes you happy? What could make you happier than now? In general, who is a happy person?). Participants’ responses were reviewed by the present investigators independently and 152 statements of happy life with 18 categories were derived from content-analysis. The list of 152 statements of happy life was administered to 517 Korean adults to assess the importance of each item for Koreans’ happy life through the objective rating scale (6-point Likert scale). Confirmatory factor analysis showed that most factors were unidimensional. The items with low reliability were deleted and some new items were added, resulting in the experimental form of the Happy Life Inventory with 156 items and 18 categories including a new category of religion. The preliminary form of the Happy Life Inventory and the Psychological Well-being scale were administered to a nationwide sample of 1503 Korean adults in order to assess their happiness through 6-point Likert scale. The responses from 877 participants were submitted to exploratory factor analysis. The items with low factor loadings were excluded and 98 items with 16 factors were included in the final version of the Happy Life Inventory. Confirmatory factor analysis of the responses from 611 subjects confirmed that the 16 factor model was appropriate and most categories had one underlying dimension with moderate to high reliabilities. Correlations between the Happy Life Inventory and the psychological well-being scale supported construct validity of the Happy Life Inventory. Suggestions for further research were discussed.     

Where You Lead,I Will Follow: Exploring Sibling Similarity in Brain and Behavior During Risky Decision Making

This exploratory study examined whether social learning increases similarity in adolescent siblings’ behavior and neural patterns during risky decision making. Participants included 86 adolescents (43 sibling dyads; younger siblings: M_age = 12.2 years; 22 females; older siblings: M_age = 14.6 years; 20 females) who completed questionnaires, and a decision‐making task during an fMRI scan. Younger siblings became more similar to their older siblings’ risky decision making after observing their older sibling take risks). Younger siblings who reported greater modeling of their older sibling, and less differentiation from them, showed increased neural similarity to their older siblings in the ventromedial prefrontal cortex, and the right anterior insula and ventral striatum, respectively. These findings highlight siblings as salient social agents in how adolescents process risky decision making.