The predictability of stock returns - a nonparametric approach

This paper reexamines the predictability of stock returns with a nonparametric model. We first identify, through a set of diagnostic tests, five lagged predictive factors from a linear model. Using these factors, we predict one-month-ahead stock index returns with a nonparametric approach. We find that our nonparametricmodel. We first identify, through a set of diagnostic tests, five lagged predictive factors from a linear model. Using these factors, we predict on -month-ahead stock index returns with a nonparametric approach. We find that our nonparametric model can correctly predict about 74% of stock index return signs. With various ex ante trading rules based on nonparametric predictions and transaction cost schedules, we then compare the performance of "managed" portfolios with that of the buy and hold portfolios. We fmd that the managed portfolios are mean-variance dominant over the buy-and-hold strategies when no or low transaction costs are assumed. When high transaction costs are assumed instead, the mean-variance dominance diminishes However,the Sharpe index of risk-adjusted portfolio performanceindicates that the managed portfolios significantly outperform the buy-and-hold strategies even for the high-transaction cost scenario. We show that the difference in performance between the managed portfolios and the buy-and-hold strategies can be partially explained by the January effect or the small firm effect. In sum, this paper demonstrates the merits of using a nonparametric approach for predicting stock returns and testing market efficiency.     

Family policy in Korea

In Korea, family policy as a public policy gained interest in the 1980s, when the Ministry of Health and Social Affairs (since January 1995 the Ministry of Health and Welfare) renamed the Maternal and Child Bureau the Family Welfare Bureau. This paper first presents a brief overview of the traditional family system and values in Korea and examines changes in economic and social indicators, changes in family functions and roles, and changes in attitudes toward family that have occurred following industrialization and urbanization. The paper then briefly explains some of the problems Korean families face today. It next examines the Family Planning Program and its results. Finally, it turns to an examination and critique of the policies and programs administered by the Family Welfare Bureau.Yeonoak Baik is a Family Advocacy Therapist for the 8th U.S. Army c/o Commander, 43rd Surgical Hospital (MA), ATTN: EAMC-SH-FAP, Room D-108, Unit #15190, APO AP, 96271-0126. She works in Korea with U.S. military soldiers and their dependents. Her research interests include child welfare, single-parent families, and domestic violence. Her MSW was received from the School of Social Work, University of Michigan, Ann Arbor.Her research interests include children of divorced families, social welfare policy, and social work administration in Korea. She received her Ph.D. in Social Welfare at Seoul National University in Korea.     

Validation of the Chinese version of the Oswestry Disability Index

This study aimed to collect evidence on the structural and substantive validity, and test-retest reliability of the Chinese version of the Oswestry Disability Index (CODI). Seventy-nine patients suffering from chronic low back pain were assessed with the CODI. The results of explorative factor analysis primarily suggested a single-factor structure with nine out of 10 items (factor loading = 0.66-0.79). The sex life item was found to load on a different factor. The Cronbach's alpha of all 10 items was 0.81 (p<0.05). When the sex life item was removed from the analysis, the alpha value was increased to 0.89 (p<0.05). The test-retest reliability was estimated based on 56 participants who completed two administrations of CODI in 48 hours. The intraclass correlation coefficient (ICC) computed for the total CODI scores was 0.86 (95% C.I. = 0.81-0.91). The reliability estimated for the item scores using Kappa statistics ranged from a high of k=0.80 for the sitting item to a low of k=0.49 for the traveling item. Kappa statistics were not available for three items. The Chinese version of the Oswestry Disability Index demonstrated satisfactory validity and test-retest reliability, and so could be considered as an appropriate instrument for assessing chronic back pain-related disability in Chinese patients in Hong Kong. Further research should address the cross-cultural and measurement issues in regard to sex life in order to further improve the test content of the instrument.     

Scheduling Truck Arrivals at an Air Cargo Terminal

We consider the scheduling of truck arrivals at an air cargo terminal. By coordinating arrivals of cargo delivery trucks with outbound flight departure schedules, some of the shipments can be transferred directly to the departing flights, while others will be stored at the terminal's storage facility and incur extra handling and storage costs. The objective is to obtain a feasible schedule so as to minimize the total cost of operations. We formulate the problem as a time‐indexed integer program and show that, even with limited number of unloading docks at the terminal, the problem is non‐trivial (NP‐hard in the strong sense). Our solution method includes an exact solution procedure to determine an optimal unloading sequence for the shipments carried by each truck, together with a Lagrangian relaxation‐based heuristic for assigning trucks to truck docks and determining truck arrival times. We conducted computational experiments to test the performance of our solution method. Computational results show that our method can generate near‐optimal solutions efficiently. Our simulation results indicate that the scheduling approach proposed in this paper has the potential to generate significant cost savings over a first‐come, first‐served approach currently used at the air cargo terminal that we observed.     

Patterns of Advanced Manufacturing Technology Utilization and Manufacturing Capabilities

The objectives of this research are first to empirically replicate Advanced Manufacturing Technology (AMT) utilization taxonomies identified in foregoing research, second to investigate the relationship between patterns of AMT utilization and manufacturing capabilities attainment, and third to explore differences in context, and performance across AMT groups. Theories of performance frontiers and capability progression provide the basis for our hypotheses. Data were collected from 224 U.S. manufacturing plants in industries considered to have potential utilizations of AMTs. A cluster analysis of the data yields a solution that closely resembles a previous AMT utilization taxonomy, including four groups labeled, respectively, as Traditionalists, Generalists, High Investors, and Designers. Significant manufacturing capability differences across these four groups indicate that plants that utilize a broader scope of AMTs enjoy a greater breadth of manufacturing capabilities. The implied capability attainment pattern is consistent with cumulative capability theory. However, the results suggest that cost capability is not included in the capability mix when broad‐based AMT utilization is the enabler of capability gains. A post hoc exploration of the AMT groups indicates significant differences in performance across the groups. Collectively, the results extend prior research by providing added insights into the possible rationale and impact of AMT utilization patterns.     

Bowling Alone in Taiwan? Political Trust and Civic Participation of Taiwanese and Their Appraisal of Liberal Democracy and Personal Wellbeing

Social Indicators Research - Based on a nationwide survey dataset collected by Taiwan’s Executive Yuan (2017) (N?=?2737) and adopting structural equation modelling with...     

Serve or skip: the power of rejection in online bottleneck matching

We consider the online matching problem, where n server-vertices lie in a metric space and n request-vertices that arrive over time each must immediately be permanently assigned to a server-vertex. We focus on the egalitarian bottleneck objective, where the goal is to minimize the maximum distance between any request and its server. It has been shown that while there are effective algorithms for the utilitarian objective (minimizing total cost) in the resource augmentation setting where the offline adversary has half the resources, these are not effective for the egalitarian objective. Thus, we propose a new Serve-or-Skip (SoS) bicriteria analysis model, where the online algorithm may reject or skip up to a specified number of requests, and propose two greedy algorithms: GriNN(t) and \({{\textsc {Grin}}^*(t)}\). We show that the SoS model of resource augmentation analysis can essentially simulate the doubled-server-capacity model, and then examine the performance of GriNN(t) and \({\textsc {Grin}^*(t)}\).     

专业、科学、本土化:中国社会工作十年的三个迷思

在中央政府大力倡导建立一支庞大社工队伍的形势下,中国社会工作已渐渐进入政府不同的职能部门,社会工作岗位的建设亦日见增多。在快速增长的过程中,中国社会工作的发展已突破了很多原来的限制,如教材不足、师资不够等。但是在关于社会工作作为一个专业在中国的发展的讨论中,至少有三个问题仍然不断缠扰着中国社会工作学界:社会工作的专业性、科学性、本土化。中国社会工作的发展一定要扎根于中国复杂的国情,有机地结合本土和非本土社会工作的技术和文化价值基因。     

Drinking: Another glass ceiling? Social drinking and alcohol use among women in Korea

Korean society is experiencing a rapid increase in alcohol consumption among women. Research on women's alcohol use has focused mostly on problems and pathological symptoms associated with alcohol use. Focusing only on problems of alcohol use risks overlooking some important social phenomena where alcohol use is a medium. We examined the association between marital status, childcare responsibility, employment status and social drinking behaviour. Our aim was to examine how these factors influence women's alcohol consumption in order to provide an empirical explanation of how the traditional division of labour limits women's social drinking practices. Findings show that women are structurally excluded from social drinking behaviour due to domestic responsibilities (as a wife and a mother). In other words, social drinking has become another glass ceiling for women. Key Practitioner Message: ● Attention should be given to structural influences on women's alcohol use; ● It is important to consider gender inequality in both formal and informal domains.