Child gender and the transition to marriage

We estimate the effect of a child's gender on the mother's probability of marriage or remarriage using data from the PSID Marital History and Childbirth and Adoption History Files. We find that the birth of a son speeds the transition into marriage when the child is born before the mother's first marriage. A competing-risks analysis shows that the positive effect of a son is stronger for marriages to the child's biological father than for other marriages. We find no significant effect of child gender on the mother's remarriage probabilities when the children are born within a previous marriage. These results are consistent with a marital-search model in which sons, more than daughters, increase the value of marriage relative to single parenthood.     

The Association Between Perceived Spirituality, Religiosity, and Life Satisfaction: The Mediating Role of Self-Rated Health

This study examined the mediating role of self-perceived health between perceived spirituality, religiosity, and life satisfaction among a stratified, random sample of college students, while controlling for gender. Although both models displayed excellent fit criteria, the perceived spirituality and life satisfaction model was fully mediated by self-perceived health χ² (n=459, 4) = 1.64, p=0.80, CFI =0.99, TLI=0.99), and the perceived religiosity and life satisfaction model was partially mediated by self-perceived health χ² (n=459, 10) = 22.29, p=0.01 CFI = 0.99, TLI = 0.99). Both models were equal for men and women. Students who describe themselves as spiritual (or religious) are likely to report greater self-perceived health and greater self-perceived health likely influences life satisfaction for both men and women. Results preliminarily support the contention that life satisfaction is related to differing reported health status, whether physical or mental, and that life satisfaction may be influenced by religiosity and spirituality engagement. Implications for colleges and universities are discussed.     

Multi-objective multi-verse optimiser for integrated two-sided assembly sequence planning and line balancing

Research in assembly optimisation is presently inclined towards integrative measures. Several benefits of simultaneously optimised Assembly Sequence Planning (ASP) and Assembly Line Balancing (ALB) have been highlighted by researchers to have better solution quality, shorter time-to-market, and minimalised error during planning. Recently, several efforts have been made to realise integrated assembly optimisation. However, none of the published research considered the two-sided assembly line problem. This paper presents an integrated ASP and ALB optimisation in a two-sided assembly environment (2S-ASPLB), which is mainly adopted in automotive assembly process. In this study, the 2S-ASPLB problem was formulated and optimised using Multi-Objective Multi-Verse Optimiser (MOMVO) by considering line efficiency, reorientation penalty, and tool change as the optimisation objectives. The computational experiments were conducted in a few stages, beginning with the identification of the best decoding approach for 2S-ASPLB. Next, the best MOMVO coefficient was studied, followed by comparing MOMVO performance with well-established multi-objective optimisation algorithms. Finally, a case study problem was presented to demonstrate applicability of the proposed model and algorithm in real-life problem. The results indicated that the priority factor (PF) decoding approach had better performance compared with others. Meanwhile, in comparison with well-established algorithms, MOMVO performed better in convergence and solution distribution. The case study results indicated the applicability of proposed 2S-ASPLB model and algorithm to improve line efficiency in assembly line. The main contribution of the research is a new 2S-ASPLB model and optimisation scheme, which can assist manufacturer in designing better assembly layout.

     

Greenhouse gases and green roofs: carbon dioxide and methane fluxes in relation to substrate characteristics

Green roof systems have been increasingly implemented to enhance vegetation cover and associated ecosystem services in urban spaces, with primary goals being the reduction of peak surface runoff, enhanced water quality, and mitigation of urban heat island effects. Recently, green roofs have also received attention as a means to enhance carbon sequestration, but direct measurements of greenhouse gas fluxes from established green roof systems are largely lacking. Here we present observations of CO₂ and CH₄ fluxes from substrates of experimental extensive green roof units that varied in vegetation type (Sedum spp., and a native meadow species mix), substrate depth, substrate type (high vs. low organic matter content), and irrigation. We predicted that substrate CO₂ effluxes would be higher in high-organic-matter substrates and that systems with high organic matter would potentially act as CH₄ sources. Substrate fluxes were low compared to natural soils, with seasonal means ranging from an efflux of 0.1–0.4 µmol CO₂ m^-2.s^-1 and uptake of ~0.00–0.04 nmol CH₄ m^-2.s^-1, with higher fluxes late in the growing season. CO₂ fluxes showed large increases in response to irrigation and were higher from the high-organic-matter substrate and with increased substrate depth. The strength of the CH₄ sink increased in response to prior irrigation treatments, and CH₄ emissions were detected only on low-organic-matter substrates early in the growing season. No effects of vegetation type were detected for either CO₂ or CH₄ flux. Our results indicate that high levels of organic matter in green roof substrates may enhance aerobic soil respiration but are not associated with CH₄ emissions, which instead were only detected in low-organic-matter substrates.

     

Media exposure,threat processing,and mitigation behaviors in Gulf Coast residents facing the co-occurring threats of COVID-19 and hurricanes

The 2020 hurricane season threatened millions of Americans concurrently grappling with COVID-19. Processes guiding individual-level mitigation for these conceptually distinct threats, one novel and chronic (COVID-19), the other familiar and episodic (hurricanes), are unknown. Theories of health protective behaviors suggest that inputs from external stimuli (e.g., traditional and social media) lead to threat processing, including perceived efficacy (self- and response) and perceived threat (susceptibility and severity), guiding mitigation behavior. We surveyed a representative sample of Florida and Texas residents (N = 1846) between April 14, 2020 and April 27, 2020; many had previous hurricane exposure; all were previously assessed between September 8, 2017 and September 11, 2017. Using preregistered analyses, two generalized structural equation models tested direct and indirect effects of media exposure (traditional media, social media) on self-reported (1) COVID-19 mitigation (handwashing, mask-wearing, social distancing) and (2) hurricane mitigation (preparation behaviors), as mediated through perceived efficacy (self- and response) and perceived threat (susceptibility and severity). Self-efficacy and response efficacy were associated with social distancing (p = .002), handwashing, mask-wearing, and hurricane preparation (ps < 0.001). Perceived susceptibility was positively associated with social distancing (p = 0.017) and hurricane preparation (p < 0.001). Perceived severity was positively associated with social distancing (p < 0.001). Traditional media exhibited indirect effects on COVID-19 mitigation through increased response efficacy (ps < 0.05), and to a lesser extent self-efficacy (p < 0.05), and on hurricane preparation through increased self-efficacy and response efficacy and perceived susceptibility (ps < 0.05). Social media did not exhibit indirect effects on COVID-19 or hurricane mitigation. Communications targeting efficacy and susceptibility may encourage mitigation behavior; research should explore how social media campaigns can more effectively target threat processing, guiding protective actions.     

Religiosity,sexual behaviors,sexual motivations,and gender: A three-year longitudinal study

Longitudinal data are critical for examining associations of religiosity with sexual behaviors and motivations during college. We use hierarchical linear modeling on five semesters of data from a diverse sample of college students (N = 735) to examine within- and between-person associations between religious service attendance and importance of religion and sexual behaviors and motivations for and against sex and consider gender as a moderator. Between-person religiosity was associated with sexual behaviors and motivations whereas within-person religiosity was not. Students' sexual motivations co-varied across semesters with their religious service attendance and importance of religion. Our results indicated more restrictive associations between religiosity and sexual motivations for women than for men.     

Within- and between-person associations among internalizing and externalizing problems during middle childhood

Internalizing and externalizing problems are likely to co-occur in childhood and are related to concurrent and prospective mental health outcomes. We examined the longitudinal relations among internalizing and externalizing problems during middle childhood utilizing the Random Intercept – Cross Lagged Panel Model. We investigated three research questions: (1) how overall levels of internalizing and externalizing problems are related, (2) whether internalizing and externalizing problems predict each other longitudinally, and (3) whether girls and boys show different longitudinal associations among internalizing and externalizing problems. Mother-reported internalizing and externalizing problems were used through first to sixth grade (N = 1364). Results showed positive random intercepts and positive within-time correlations of internalizing and externalizing problems. Further, internalizing problems predicted externalizing problems at the within-person level. Although previous research mostly has shown a significant effect from externalizing problems to internalizing problems, the current study shows that when within- and between-person variance are disentangled, internalizing problems also may predict externalizing problems.     

Clocks and Trees: Isomorphic Dutch Auctions and Centipede Games

We report an experiment on effects of varying institutional format and dynamic structure of centipede games and Dutch auctions. Centipede games with a clock format unravel, as predicted by theory but not reported in previous literature on two‐player tree‐format centipede games. Dutch auctions with a tree format produce bids close to risk neutral Nash equilibrium bids, unlike previous literature on clock‐format Dutch auctions. Our data provide a new, expanded set of stylized facts which may provide a foundation for unified modeling of play in a class of games that includes centipede games and Dutch auctions.     

FINANCIAL INTEGRATION: A NEW METHODOLOGY AND AN ILLUSTRATION

This paper develops a simple methodology to test for asset integration, and applies it within and between American stock markets. Our technique relies on estimating and comparing expected risk‐free rates across assets. Expected risk‐free rates are allowed to vary freely over time, constrained only by the fact that they must be equal across (risk‐adjusted) assets in well‐integrated markets. Assets are allowed to have standard risk characteristics, and are constrained by the Fama and French factor model of covariances over short time periods. We find that internal integration in the S&P 500 market is never rejected and is not generally rejected in the NASDAQ. Integration between the NASDAQ and the S&P, however, is always rejected dramatically. (JEL: G14)