Racial identity, racial discrimination, perceived stress, and psychological distress among African American young adults

This study examines the direct and indirect relationships among racial identity, racial discrimination, perceived stress, and psychological distress in a sample of 555 African American young adults. A prospective study design was used to assess the influence of two dimensions of racial identity attitudes (i.e., centrality and public regard) on other study variables to investigate the relationship between racial identity attitudes and psychological distress. The results show some evidence of a direct relationship between racial centrality and psychological distress, as well as evidence of indirect relationships for both centrality and public regard through the impact of racial discrimination and perceived stress. In addition, racial centrality was both a risk factor for experiencing discrimination and a protective factor in buffering the negative impact of discrimination on psychological distress. Results are discussed within the context of identifying multiple pathways to psychological well-being for African American young adults within the context of racial discrimination.     

A Longitudinal Study of Depressive Symptoms and Marijuana Use in a Sample of Inner‐City African Americans

The association between marijuana use and depressive symptoms was examined longitudinally in a sample of 622 African American youth, interviewed on six occasions, using hierarchical linear modeling (HLM). We considered whether depressive symptoms predicted changes in marijuana use and vice versa from high school through the transition into young adulthood. We also examined gender differences in these behaviors over time. The results indicated that depressive symptoms predicted later marijuana use only for males. Marijuana use did not predict later depressive symptoms for females or males. These findings are consistent with a unidirectional hypothesis indicating that marijuana use may play a role as mood regulator among young males, but not among females. Research findings also indicate that females with lower depressive symptoms use more marijuana than females who report high depressive symptoms. These findings did not change even after controlling for the effects of using other substances at previous stages, school achievement, and demographics factors. These results suggest that depressive symptoms may be an antecedent of marijuana use among African American males.     

Supplementing a survey with respondent Twitter data to measure e-cigarette information exposure

ABSTRACT

Social media data are increasingly used by researchers to gain insights on individuals’ behaviors and opinions. Platforms like Twitter provide access to individuals’ postings, networks of friends and followers, and the content to which they are exposed. This article presents the methods and results of an exploratory study to supplement survey data with respondents’ Twitter postings, networks of Twitter friends and followers, and information to which they were exposed about e-cigarettes. Twitter use is important to consider in e-cigarette research and other topics influenced by online information sharing and exposure. Further, Twitter metadata provide direct measures of user’s friends and followers as opposed to survey self-reports. We find that Twitter metadata provide similar information to survey questions on Twitter network size without inducing recall error or other measurement issues. Using sentiment coding and machine learning methods, we find Twitter can elucidate on topics difficult to measure via surveys such as online expressed opinions and network composition. We present and discuss models predicting whether respondents’ tweet positively about e-cigarettes using survey and Twitter data, finding the combined data to provide broader measures than either source alone.     

Assessing job self-efficacy and organizational commitment considering a mediating role of information asymmetry

This study establishes a model by drawing from key postulates and findings under information asymmetry to explain the formation of organization commitment and job self-efficacy. In the proposed model, organizational commitment and job self-efficacy are influenced indirectly by social support, knowledge creation, and information intensity via the mediation of decision-making quality and perceived opportunism. Knowledge creation is influenced directly by both social support and information intensity. Empirical testing of this model, by investigating personnel from firms in one of Taiwan's well-known industrial zones, confirms the applicability of information asymmetry in understanding employees’ organizational commitment and job self-efficacy. The test results indicate that all the model paths except one (linking perceived opportunism and job self-efficacy) are significant. Finally, the research provides managerial implications and limitations.     

Extreme probabilities for contingency tables under row and column independence with application to fisher's exact test

Theorerms are proved for the maxima and minima of IIR_i!/IIC_j!/T!II_yij ! over r× c contingcncy tables Y=(y_ij) with row sums R₁,…,R_r, column sums C₁,…,C_c, and grand total T. These results are imlplemented into the network algorithm of Mehta and Patel (1983) for computing the P-value of Fisher's exact test for unordered r×c contingency tables. The decrease in the amount of computing time can be substantial when the column sums are very different.     

The strengths and limitations of demography,and the works of W.D. Borrie

This lecture examines the nature of demography and how the work of W.D. Borrie relates to it. The principal topics are: the meaning of ‘demography’, changes in the discipline, the uniqueness of demography, population theories and ideologies, and the writings of W.D. Borrie.