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A Paradoxical Result in Estimating Regression Coefficients
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| Pengarang | : | Thaddeus Tarpey |
| Nama Majalah/Jurnal | : | The American Statistician |
| Volume / Edisi | : | 68 (No. 4) |
| Halaman | : | 271-276 |
| Abstrak | : | This article presents a counterintuitive result regarding the estimation of a regression slope coefficient. Paradoxically, the precision of the slope estimator can deteriorate when additional information is used to estimate its value. In a randomized experiment, the distribution of baseline variables should be identical across treatments due to randomization. The motivation for this article came from noting that the precision of slope estimators deteriorated when pooling baseline predictors across treatment groups. |
The Promise of Prediction Contests
| Pengarang | : | Phillip E. Pfeifer |
| Nama Majalah/Jurnal | : | The American Statistician |
| Volume / Edisi | : | 68 (No. 4) |
| Halaman | : | 264-270 |
| Abstrak | : | This article examines the prediction contest as a vehicle for aggregating the opinions of a crowd of experts. After proposing a general definition distinguishing prediction contests from other mechanisms for harnessing the wisdom of crowds, we focus on point-forecasting contests—contests in which forecasters submit point forecasts with a prize going to the entry closest to the quantity of interest. We first illustrate the incentive for forecasters to submit reports that exaggerate in the direction of their private information. Whereas this exaggeration raises a forecaster's mean squared error, it increases his or her chances of winning the contest. And in contrast to conventional wisdom, this nontruthful reporting usually improves the accuracy of the resulting crowd forecast. The source of this improvement is that exaggeration shifts weight away from public information (information known to all forecasters) and by so doing helps alleviate public knowledge bias. In the context of a simple theoretical model of overlapping information and forecaster behaviors, we present closed-form expressions for the mean squared error of the crowd forecasts which will help identify the situations in which point forecasting contests will be most useful. |
Race-based marginalization and private racial regard in Asian Americans: Self-esteem and nativity as moderators.
| Pengarang | : | Cheng, Hsiu-Lan; Zhang, Jing; Su, Jenny; Kim, Helen Youngju. |
| Nama Majalah/Jurnal | : | Asian American Journal of Psychology |
| Volume / Edisi | : | 11 (No. 3) |
| Halaman | : | 187-197 |
| Abstrak | : | In a sample of 881 Asian American college students, the present study examined self-esteem and nativity status (i.e., non–U.S.-born vs. U.S.-born) as moderators in the associations between race-based marginalization experiences (i.e., awareness of the perpetual foreigner stereotype and perceived racial discrimination) and private racial regard. Results indicated that there was a significant 3-way interaction between awareness of the perpetual foreigner stereotype, self-esteem, and nativity status, but there was not a significant 3-way interaction between perceived racial discrimination, self-esteem, and nativity status. Specifically, we found that self-esteem buffered the negative relationship between awareness of the perpetual foreigner stereotype and private racial regard for U.S.-born Asian Americans, but not non–U.S.-born Asian Americans. Among Asian American college students who were born in the United States, awareness of the perpetual foreigner stereotype and private racial regard were significantly and negatively correlated when self-esteem was low, but not when self-esteem was high. This pattern, however, was not found among Asian American college students who were born outside of the United States. The present findings suggest that self-esteem may be a particular important psychological resource that may serve as a protective factor to cancel out the negative link between awareness of the perpetual foreigner stereotype and private racial regard among U.S.-born Asian American individuals. |
The relationship between postmigration living difficulties, social support, and psychological distress of Burmese refugees in the United States.
| Pengarang | : | Li, Youming,Jia, Chen |
| Nama Majalah/Jurnal | : | Asian American Journal of Psychology |
| Volume / Edisi | : | 11 (No. 3) |
| Halaman | : | 179-186 |
| Abstrak | : | This study examines the relationship between postmigration living difficulties (PMLDs), social support, and the mental health of Chin-Burmese refugees resettled in the United States. Data were collected from 242 respondents by means of survey through convenience and snowball sampling methods. Respondents completed self-report measures of postmigration problems, social support, and psychological distress. The mean age of respondents was 35.45 years; 53.3% were male, 79.3% were married, and 69% were employed. The mean years of residency in the United States was 5.63. Across the whole sample, 34.3% reported symptoms of psychological distress. More than one third of respondents reported experiencing difficulties in access to health care and social services. The most reported PMLDs were difficulties pertaining to communication, accessing health care, and worries about family back home. The number of PMLDs (β = .39, p < .001) and perceived social support (β = −.16, p < .01) significantly predicted psychological distress. Experiencing serious PMLDs significantly increases the risk of psychological distress. These findings demonstrated the importance of implementing appropriate and timely mental health interventions to effectively meet the needs of refugees as they adjust to the cultural life in the United States. A lack of attention to their mental health needs can translate to inadequate mental health care. Implications for practice are discussed. |
Dissonant Conclusions When Testing the Validity of an Instrumental Variable
| Pengarang | : | Fan Yang |
| Nama Majalah/Jurnal | : | The American Statistician |
| Volume / Edisi | : | 68 (No. 4) |
| Halaman | : | 253-263 |
| Abstrak | : | An instrument or instrumental variable is often used in an effort to avoid selection bias in inference about the effects of treatments when treatment choice is based on thoughtful deliberation. Instruments are increasingly used in health outcomes research. An instrument is a haphazard push to accept one treatment or another, where the push can affect outcomes only to the extent that it alters the treatment received. There are two key assumptions here: (R) the push is haphazard or essentially random once adjustments have been made for observed covariates, (E) the push affects outcomes only by altering the treatment, the so-called “exclusion restriction.” These assumptions are often said to be untestable; however, that is untrue if testable means checking the compatibility of assumptions with other things we think we know. A test of this sort may result in a collection of claims that are individually plausible but mutually inconsistent, without clear indication as to which claim is culpable for the inconsistency. We discuss this subject in the context of our on-going study of the effects of delivery by cesarean section on the survival of extremely premature infants of 23–24 weeks gestational age. Supplementary materials for this article are available online. |
Intergenerational cultural conflict, assertiveness, and adjustment among Asian Americans.
| Pengarang | : | Pham, Savannah; Lui, P. Priscilla; Rollock, David. |
| Nama Majalah/Jurnal | : | Asian American Journal of Psychology |
| Volume / Edisi | : | 11 (No. 3) |
| Halaman | : | 168-178 |
| Abstrak | : | According to acculturation gap–distress theory, intergenerational cultural conflict stems from parent–offspring acculturation mismatch. Greater acculturation-based family conflict has been linked to poorer psychological adjustment among Asian American offspring, especially emerging adults. Whereas trait assertiveness often is shown to buffer the relation between interpersonal conflict and psychological distress among Euro Americans, it remains unknown how assertiveness contributes to Asian Americans’ psychological adjustment both directly and jointly with intergenerational cultural conflict. Considering Asian cultural values of filial piety and obedience, high levels of assertiveness—a set of intrapersonal characteristics that prioritizes individualistic needs over family harmony and group needs—may intensify the relations between intergenerational cultural conflict and adjustment outcomes. Asian American college students (N = 141, 58.2% women, Mage = 20.86) completed surveys assessing their levels of intergenerational cultural conflict, assertiveness, and three psychological adjustment outcomes (depression symptoms, negative affect, and subjective well-being). Intergenerational cultural conflict was positively associated with depression symptoms. Assertiveness was correlated with negative affect and depression symptoms negatively, and with subjective well-being positively. Contrary to hypothesis, assertiveness did not moderate the relations between intergenerational cultural conflict and psychological adjustment. Whereas trait assertiveness can be promotive of psychological adjustment outcomes among Asian Americans, it may not affect the degree to which intergenerational cultural conflict is linked to offspring adjustment outcomes. |
Are Nonprofit Antipoverty Organizations Located Where They Are Needed? A Spatial Analysis of the Greater Hartford Region
| Pengarang | : | Jun Yan |
| Nama Majalah/Jurnal | : | The American Statistician |
| Volume / Edisi | : | 68 (No. 4) |
| Halaman | : | 243-252 |
| Abstrak | : | The geographic distribution of nonprofit antipoverty organizations has important implications for economic development, social services, public health, and policy efforts. With counts of antipoverty nonprofits at the census tract level in Greater Hartford, Connecticut, we examine whether these organizations are located in areas with high levels of poverty with a spatial zero-inflated-Poisson model. Covariates that measure need, resources, urban structure, and demographic characteristics are incorporated into both the zero-inflation component and the Poisson component of the model. Variation not explained by the covariates is captured by the combination of a spatial random effect and an unstructured random effect. Statistical inferences are done within the Bayesian framework. Model comparison with the conditional predictive ordinate suggests that the random effects and the zero-inflation are both important components in fitting the data. All three need measures—proportion of people below the poverty line, unemployment rate, and rental occupancy—are found to have significantly positive effect on the mean of the count, providing evidence that antipoverty nonprofits tend to locate where they are needed. The dataset and R/OpenBUGS code are available in supplementary materials online. |
Revisiting the bamboo ceiling: Perceptions from Asian Americans on experiencing workplace discrimination.
| Pengarang | : | Widiyanto, Priyo |
| Nama Majalah/Jurnal | : | Asian American Journal of Psychology |
| Volume / Edisi | : | 11 (No. 3) |
| Halaman | : | 158-167 |
| Abstrak | : | Although Asians comprise 6.2% of the overall U.S. labor market and are the fastest growing and most diverse racial group in the country, they are the least likely among all race/ethnic groups to become executive leaders, especially Asian women. Scholarship on the bamboo ceiling has emphasized the model minority myth as an impediment for Asian Americans to advance into executive-level management positions; however, there has also been a dearth of research on Asian Americans and their experiences with workplace discrimination. Using data from the second wave of the 2016 National Asian American Survey (n = 1,013), this study compares the responses of Asian Americans with other major race/ethnic groups, to include 10 Asian subgroups, to examine the prevalence of perceived discriminatory treatment in denied promotion decisions as a result of their race/ethnicity. The findings identify sources of heterogeneity and highlight higher degrees of perceived discrimination in denied promotion decisions, to include a disadvantage among females and a U.S.-born advantage, among several Asian ethnicities. |
An Introduction to Practical Sequential Inferences via Single-Arm Binary Response Studies Using the binseqtest R Package
| Pengarang | : | Jennifer L. Kirk |
| Nama Majalah/Jurnal | : | The American Statistician |
| Volume / Edisi | : | 68 (No. 4) |
| Halaman | : | 230-242 |
| Abstrak | : | We review sequential designs, including group sequential and two-stage designs, for testing or estimating a single binary parameter. We use this simple case to introduce ideas common to many sequential designs, which in this case can be explained without explicitly using stochastic processes. We focus on methods provided by our newly developed R package, binseqtest, which exactly bound the Type I error rate of tests and exactly maintain proper coverage of confidence intervals. Within this framework, we review some allowable practical adaptations of the sequential design. We explore issues such as the following: How should the design be modified if no assessment was made at one of the planned sequential stopping times? How should the parameter be estimated if the study needs to be stopped early? What reasons for stopping early are allowed? How should inferences be made when the study is stopped for crossing the boundary, but later information is collected about responses of subjects that had enrolled before the decision to stop but had not responded by that time? Answers to these questions are demonstrated using basic methods that are available in our binseqtest R package. Supplementary materials for this article are available online. |
Reference Class Forecasting: Resolving Its Challenge to Statistical Modeling
| Pengarang | : | Robert F. Bordley |
| Nama Majalah/Jurnal | : | The American Statistician |
| Volume / Edisi | : | 68 (No. 4) |
| Halaman | : | 221-229 |
| Abstrak | : | Statisticians generally consider statistical modeling superior (or at least a useful supplement) to experience-based intuition for estimating the outputs of a complex system. But recent psychological research has led to an enhancement of experience-based intuition known as reference class forecasting. The reference class forecasting approach has been championed as a superior alternative to statistical modeling and is already well-regarded in the planning community. This presents a challenge to statistical modeling. To address this challenge, this article uses a Bayesian approach for combining the reference class forecast and the model-based forecast. The Bayesian prior is informed by the reference class information. A likelihood function was constructed to reflect the model’s information. This approach was used to estimate healthcare costs under a voluntary employee benefit association (VEBA). The resulting Bayesian posterior forecast had lower variance (and lower forecast error) than either the model-based forecast or the reference-class forecast. |