Note: A note on the production and inventory systems taking account of time value

This paper deals with the optimal inventory decisions taking account of time value by applying the concept of the present value method, and modifies the bounds for the optimal cycle time described in Chung et al. (Production Planning & Control, 1998, 9, 580–584). A modified algorithm to compute the optimal cycle time is developed to improve the paper of Chung et al. Finally, a numerical example is given to illustrate the algorithm discussed in this paper.     

Aggressive and Prosocial Peer Group Functioning: Effects on Children's Social,School, and Psychological Adjustment

This study examined the effects of aggressive and prosocial contexts of peer groups on children's socioemotional and school adjustment. Data on informal peer groups, social functioning, and different aspects of adjustment were collected from multiple sources in a sample of elementary school children (149 boys, 181 girls; M age = 10 years). Multilevel analyses indicated that group aggressive and prosocial orientations made direct contributions to children's social, school, and psychological functioning. Group contexts also moderated the individual‐level relations between social behavior and self‐perceptions; prosocial behavior was associated with social or scholastic self‐perceptions more evidently in low prosocial and high aggressive groups. The results suggest that the peer group is an important context for children's performance and adjustment in various domains.     

Risk‐Based Probabilistic Approach to Assess the Impact of False Mussel Invasions on Farmed Hard Clams

The purpose of this article is to provide a risk‐based predictive model to assess the impact of false mussel Mytilopsis sallei invasions on hard clam Meretrix lusoria farms in the southwestern region of Taiwan. The actual spread of invasive false mussel was predicted by using analytical models based on advection‐diffusion and gravity models. The proportion of hard clam colonized and infestation by false mussel were used to characterize risk estimates. A mortality model was parameterized to assess hard clam mortality risk characterized by false mussel density and infestation intensity. The published data were reanalyzed to parameterize a predictive threshold model described by a cumulative Weibull distribution function that can be used to estimate the exceeding thresholds of proportion of hard clam colonized and infestation. Results indicated that the infestation thresholds were 2–17 ind clam^?1 for adult hard clams, whereas 4 ind clam^?1 for nursery hard clams. The average colonization thresholds were estimated to be 81–89% for cultivated and nursery hard clam farms, respectively. Our results indicated that false mussel density and infestation, which caused 50% hard clam mortality, were estimated to be 2,812 ind m^?2 and 31 ind clam^?1, respectively. This study further indicated that hard clam farms that are close to the coastal area have at least 50% probability for 43% mortality caused by infestation. This study highlighted that a probabilistic risk‐based framework characterized by probability distributions and risk curves is an effective representation of scientific assessments for farmed hard clam in response to the nonnative false mussel invasion.     

Individual Disaster Assistance For Socially Vulnerable People: Lessons Learned From the Pohang Earthquake in the Republic of Korea

The Republic of Korea has been considered to be relatively safe from earthquake hazards because of the geological location of the Korean Peninsula, which has a low level of intraplate seismic activity. However, an earthquake with a moment magnitude of 5.4 struck the city of Pohang on November 15, 2017, causing 90 casualties and 52 million USD in property losses. During the recovery process after the earthquake, the Korean government provided individual disaster assistance to victims who reported their damages. However, the government disaster assistance could have been unfairly distributed among the socially vulnerable victims who essentially relied on that assistance. This study identifies whether the government disaster assistance was fairly distributed to socially vulnerable victims using a statistical model based on the data from the Pohang earthquake that occurred in 2017 in Korea. A conceptual model was constructed using a structural equation model (SEM) of three factors—social vulnerability, physical vulnerability, and the amount paid out in individual disaster assistance. Furthermore, interviews with and a survey of the victims were conducted to verify the problems identified by the conceptual model. This study found that socially vulnerable victims were less likely to take advantage of the government disaster assistance program.     

Cox regression for current status data with mismeasured covariates

Covariate measurement error problems have been extensively studied in the context of right‐censored data but less so for current status data. Motivated by the zebrafish basal cell carcinoma (BCC) study, where the occurrence time of BCC was only known to lie before or after a sacrifice time and where the covariate (Sonic hedgehog expression) was measured with error, the authors describe a semiparametric maximum likelihood method for analyzing current status data with mismeasured covariates under the proportional hazards model. They show that the estimator of the regression coefficient is asymptotically normal and efficient and that the profile likelihood ratio test is asymptotically Chi‐squared. They also provide an easily implemented algorithm for computing the estimators. They evaluate their method through simulation studies, and illustrate it with a real data example. The Canadian Journal of Statistics 39: 73–88; 2011 © 2011 Statistical Society of Canada     

Exploratory analysis of verbal aggression in romantic relationships among unmarried men and women: Predictive patterns by gender and race

This is an exploratory study that examined verbal aggression in romantic relationships among unmarried Black and White women and men as a function of gender and race. We employed an ecological approach to examine the receipt of verbal aggression separately for men and women at the levels of individual, relationship, and community. We also explored whether gender-specific correlates of verbal aggression interacted with race. Analyses were based on a sample of 212 women and 133 men in non-marital romantic relationships recruited from 21 U.S. cities for a larger study. Linear mixed-effects models revealed that factors related to experiencing verbal aggression differed substantially for unmarried women and men in romantic relationships. Interesting racial differences also emerged distinctly for women and men.     

Association between hand-grip strength and erectile dysfunction in older men

Abstract

Objectives: To evaluate the association between handgrip strength and erectile dysfunction (ED) in community-dwelling older men.

Methods: This cross-sectional study included 1771 participants of the Dong-gu Study. Handgrip strength was measured with a handheld dynamometer. ED was assessed with the Korean version of the International Index of Erectile Function (IIEF). ED was categorized as none to mild (IIEF-EF scores of 13–30) and moderate to severe (IIEF-EF scores of 0–12). Multivariable logistic regression was conducted with adjustment for potential confounders.

Results: The proportion of men with moderate to severe ED was 48.8%. The age-adjusted ED score increased with increasing quartile of handgrip strength (11.0, 12.4, 13.4, and 14.0 in the lowest, second, third, and highest quartiles, respectively). After adjustment for potential confounders, greater handgrip strength was associated with a lower risk of ED (odds ratio (OR): 0.82 per 5?kg; 95% confidence interval (CI): 0.74–0.90). In addition, a high level of moderate to vigorous physical activity was associated with a lower risk of ED (OR: 0.75; 95% CI: 0.61–0.93).

Conclusion: In this study, aging men with greater handgrip strength had a lower risk of ED. This result suggests that reduced physical functioning may contribute to ED.     

From passive assistance to capacity building: assessing the Child Development Fund in Hong Kong

Poverty was not a major issue in Hong Kong before the 1990s. After the Asian financial crisis, the government admitted that poverty was growing and demanded attention. While passive assistance was maintained, increasing emphasis was placed on capacity building to promote self-reliance. The Child Development Fund was introduced to combat intergenerational poverty by developing children's capacity and assets, especially through mentorship. On the basis of published data and interviews with social workers, the project should be considered a success, but it was not without problems. The contribution of social workers to the project was significant but received little government recognition.     

From Caregivers to Caretakers: The Impact of Family Roles on Ethnicity Among Children of Korean and Chinese Immigrant Families

Scholars have long examined the effects of family and community on ethnicity, but they have less to say on why some children may be more receptive to the positive influences of ethnic communities than siblings within the same family. As more immigrants struggle to adapt to the needs and demands of the new global economy, many families are turning to alternative caregiving arrangements that significantly impact the long-term ethnic identities of the second generation. The article considers how adult-age children of immigrants negotiate the emotional disconnects created by these varying contexts of care depending on their individual role within the family and how it shapes their views on ethnicity and culture in their own adult lives. The study focuses in-depth on fourteen semi-structured, in-person interviews with adult-age children of Asian immigrant families in the NY-NJ metropolitan area. Depending on their social status, children of immigrants are integrated into their families: as cultural brokers expected to mediate and care for their family members, as familial dependents who rely on their parents for traditional caregiving functions, or as autonomous caretakers who grow up detached from their parents. I argue that because of their intense engagement with family, cultural brokers describe their ethnic-centered experiences as evoking feelings of reciprocated empathy, whereas on the other end, autonomous caretakers associate their parents’ ancestral culture with ethnocentric exclusion. Depending on how they are able to negotiate the cultural divide, familial dependents generally view their parents’ culture and immigrant experiences through the hierarchical lens of emulation.