Frequency domain bootstrap for ratio statistics under long-range dependence

A frequency domain bootstrap (FDB) is a common technique to apply Efron’s independent and identically distributed resampling technique (Efron, 1979) to periodogram ordinates – especially normalized periodogram ordinates – by using spectral density estimates. The FDB method is applicable to several classes of statistics, such as estimators of the normalized spectral mean, the autocorrelation (but not autocovariance), the normalized spectral density function, and Whittle parameters. While this FDB method has been extensively studied with respect to short-range dependent time processes, there is a dearth of research on its use with long-range dependent time processes. Therefore, we propose an FDB methodology for ratio statistics under long-range dependence, using semi- and nonparametric spectral density estimates as a normalizing factor. It is shown that the FDB approximation allows for valid distribution estimation for a broad class of stationary, long-range (or short-range) dependent linear processes, without any stringent assumptions on the distribution of the underlying process. The results of a large simulation study show that the FDB approximation using a semi- or nonparametric spectral density estimator is often robust for various values of a long-memory parameter reflecting magnitude of dependence. We apply the proposed procedure to two data examples.     

Values and happiness among Asian adolescents: a cross-national study

Despite policy efforts to increase adolescent happiness, their impact has been unsatisfactory. Their limited impact may be rooted from a discrepancy between values that adolescents pursued and those that the policies were based on. To provide policy implications, our study aims to identify prevailing values for South Korean, Japanese, and Chinese adolescents and to examine the relationship between the values and self-rated happiness (SRH). A cross-sectional study was conducted using survey data collected on approximately 2000 middle and high school students (7th to 12th school grade) from each country in 2008. Firstly, an explanatory factor analysis was conducted to identify salient adolescent values from each country. Subsequently, a multiple logistic regression analysis was conducted for each population group to examine the relationship between the identified values and adolescent SRH after controlling for sociodemographic characteristics. We found that benevolence and altruism were positively associated with adolescent SRH in all three population groups. Patriarchy was associated with SRH positively in Chinese yet inversely in Japanese. Success pursuit was inversely associated with SRH in Korean. Policy efforts based on values of communities or social harmony may benefit adolescents’ SRH in these three countries.     

Racial Identity–Related Differential Attributions of Inadequate Responses to Hurricane Katrina: A Social Identity Perspective

This study examines the attribution of responsibility for the problematic response to Hurricane Katrina in the fall of 2005. Based on social identity theory, the study compared the attribution with racism and non-racism factors (situational vs. dispositional attributions) between African American and European American students (n = 505). As hypothesized, African American identity was related to greater racism attribution, even after controlling for demographics, faith factors, and cognitive-emotional reactions to the hurricanes. European American identity was associated with more executive-responsibility attributions, but the effect vanished after adjusting other factors. The study underscores the importance of acknowledging group identity rather than an overarching American identity in exploring the race effect after a national collective trauma. The consequential implications for disaster planning, future research investigation, and social service delivery are discussed.     

Import competition and job displacement: A case study of Korean manufacturing industries

This paper investigates the impact of import competition on job displacement in Korean manufacturing industries. Using a regression model for the period of 1993–2003, the empirical results show that import competition raises the job displacement rate in the Korean manufacturing sector but the elasticity is negligible in its magnitude. Worker characteristics, such as gender, age, job tenure, and education level, proved to be significant in determining the displacement rate. Characteristics of displaced workers in high import-competing industries are also investigated based on the survey data. Workers who lost their jobs in these sectors were slightly older, less educated, and had longer job tenure than the workers in the other groups.     

All Politics is Not Local: National Forces in State Abortion Initiatives

Objective. Although research suggests that national forces can play a role in local and state elections, most of this work has only recently begun to examine the potential role of national forces in state or local ballot initiative or referenda elections. Methods. Our research addresses this gap in the literature by exploring the influence of national forces, such as the timing of elections, Supreme Court rulings, the activities of interest groups, and public opinion, on state direct legislation elections. We incorporate national forces into the morality politics framework and derive specific hypotheses. We then test these hypotheses by conducting a multivariate analysis of county–level voting patterns across 16 abortion–related direct legislation elections. Results. Our results confirm most of the hypotheses derived from the morality politics framework, including those concerning the role of national forces. Conclusions. Voting patterns on abortion tend to be influenced by the presence of presidential elections, Supreme Court rulings, interest–group activity, public opinion, partisanship, college education, and conservative religious forces. We discuss the implications of our findings for research on elections, abortion policy, and morality politics.     

Restricted minimax robust designs for misspecified regression models

The authors propose and explore new regression designs. Within a particular parametric class, these designs are minimax robust against bias caused by model misspecification while attaining reasonable levels of efficiency as well. The introduction of this restricted class of designs is motivated by a desire to avoid the mathematical and numerical intractability found in the unrestricted minimax theory. Robustness is provided against a family of model departures sufficiently broad that the minimax design measures are necessarily absolutely continuous. Examples of implementation involve approximate polynomial and second order multiple regression.     

Accuracy and bias in self-perception of performance: Narcissism matters in Korea as well

Debates regarding the nature of self-enhancement versus accurate self-assessment have been active among psychologists for decades. More recently, researchers have become interested in the panculturality of self-enhancement. Some researchers argue that self-enhancement is universal and present within all cultures. Others declare self-enhancement to be a Western tendency, with self-diminishment being the norm among East Asians. Importantly, the majority of such studies have not compared self-perceptions against objective external criteria, especially those with East Asians. Furthermore, the link between narcissism and self-enhancement has been largely overlooked within Korean samples. To address such gaps, we utilized scores on an objective test as a criterion to investigate the accuracy of Koreans’ self-assessments of performance, as well as how individual differences in narcissism are related to such assessments. A sample of Korean students (N = 146; 71 women) completed self-report measures of narcissism and self-esteem, and took a listening comprehension quiz. Estimated and actual scores were collected and used to compute self-enhancement scores. Results demonstrated that Koreans’ self-perceptions of performance on the quiz were quite accurate. As has been found in Western cultures, narcissism was related to self-enhancement.     

Wealth Accumulation Inequality: Does Investment Risk Tolerance and Equity Ownership Drive Wealth Accumulation?

This study examined the savings aspect of wealth accumulation by estimating differences in financial risk tolerance and equity ownership among individual investors. Data were obtained from a proprietary dataset that collected over 15,000 risk-tolerance attitude responses between late 2007 and early 2013. Two research methodologies were utilized: cluster analysis and ANCOVA. The cluster analysis identified four investor profiles: (a) young lower-income women, (b) young unmarried men, (c) young college-educated men, and (d) older men with high income and education. Results from the ANCOVA test indicated that each cluster had significantly different levels of equity ownership, controlling for financial risk tolerance. Results provide a framework and methodology for future research on issues related to wealth inequality, investment behavior, and risk attitudes. The ability to group individuals similarly can be an important tool for researchers, policy makers, social activists, financial advisers, financial counselors, and educators when analyzing the household and macroeconomic wealth profile of United States residents.     

Novel symptom questionnaire for the differential diagnosis of detrusor underactivity and bladder outlet obstruction in men

Objective: To develop a questionnaire for the differential diagnosis of detrusor underactivity (DUA) and bladder outlet obstruction (BOO) without performing invasive pressure flow studies.

Study design and methods: Symptoms of men with DUA were analyzed and compared with those of men with BOO using eight questions from the developing questionnaire. Patients with DUA have a bladder contractility index (PdetQmax+5xQmax) less than 100, whereas those with BOO have a BOO index (PdetQmax?2xQmax) greater than 40 in urodynamic studies (UDS). Men with detrusor overactivity in UDS and neurogenic issues were excluded from the analysis. One urologist reviewed patients’ medical records, and responded to eight questions without using information from UDS. Scores in the developing questionnaire were then compared to make a differential diagnosis between DUA and BOO.

Results: Overall, 318 men who underwent UDS were included. Symptoms were compared in patients diagnosed with DUA without BOO (n?=?165) and BOO without DUA (n?=?153). Questions 1, 2, 4, 5, 6, and 7 were significantly different between groups. The sensitivity and specificity of the questionnaire were 95.8% and 95.4%, respectively, for predicting DUA in patients with scores greater than 45 points (cutoff value).

Conclusions: Men with DUA and BOO may be distinguished using a developing questionnaire without invasive evaluation. Men with scores greater than 45 points would be expected to have DUA but not BOO.