Implementation of JIT purchasing: An integrated approach

This article addresses the necessity of integration between buyer and supplier for effective implementation of the JIT system. An integrated lot-splitting model of facilitating multiple shipments in small lots is developed and compared with the existing approach in a simple JIT environment, single-buyer-single-supplier, under deterministic conditions for a single product. It is shown that the optimal policy adopted by the integrated approach can provide a strong and consistent cost-minimizing effect for both buyer and supplier over the existing approach.     

Decomposition of the difference between two rates with hierarchical factors

A decomposition method for the difference between two rates when data are classified by two factors, one of which may be considered as a more direct factor than the other for the event under consideration, is presented in this paper. The two factors are treated as hierarchical and thus this method is conceptually different from the decomposition methods of Kitagawa (1955) and Das Gupta (1978), in which two factors are treated as symmetrical. Our method is shown to be a balanced version of the Cho-Retherford (1973) decomposition method. Analyses of neonatal mortality rates using our method are presented as an example.     

Pay-What-You-Want – Praxisrelevanz und Konsumentenverhalten

Pay-What-You-Want (PWYW) is a participative pricing mechanism which is characterized by the fact that consumers have maximum control over the price they pay. We discuss the business relevance of PWYW and extend the findings of Kim et al. (2009) using latent class regression. Two different classes can be identified and transaction prices are explained by psycho- and socio-demographics. The estimation of the parameters shows that the internal reference price is a good predictor for the prices in class 1, whereas in the 2nd class the level of fairness and satisfaction with the product positively affect the final transaction prices.     

On the dynamics of populations with two age groups

By restricting the number of age groups to two and by introducing continued fractions, the dynamics of populations with deterministically changing vital rates are completely specified at all times. Explicit expressions for the sequence of the product of population projection matrices are given. From these, relative age distribution and reproductive values to any desired accuracy are obtained as functions of the vital rates. Thus, the results given in this paper are stronger than any existing weak ergodic theorems.     

Defining Nations in Asia and Europe: A Comparative Analysis of Ethnic Return Migration Policy1

We argue that regional comparison of East Asian and European ethnic return migration policy offers important new perspectives on nationhood, nondiscrimination norms, and trans‐nationality. We find that despite international nondiscrimination norms, preferential ethnic return policy is common in both regions. These policies at least implicitly define the nation as existing across borders. However, there are significant regional differences. East Asian states use co‐ethnic preferences instrumentally for economic goals and also offer preferential treatment of co‐ethnic foreign investors. European states offer preferences to coethnics to protect these populations or express symbolic ties, sometimes at great expense. Thus, in Europe the state has an obligation to assist coethnics abroad, but in Asia, foreign coethnics assist the state.     

Generalizability of Gottman and Colleagues' Affective Process Models of Couples' Relationship Outcomes

The generalizability of Gottman et al's. (1998) affective process models was examined using a community-based sample of 85 married or cohabiting couples with at-risk backgrounds. Predictive associations between affective processes assessed at about age 21 years and relationship status and satisfaction approximately 2.5 years later were examined. The major findings of Gottman et al. failed to replicate. In particular, men's rejection of their partners' influence, the lack of men's deescalation of partners' negative affect, and women's negative start up were not predictive of relationship status. Further, differences in affective processes were found when comparing discussion sessions of the men's versus the women's chosen topics. The findings suggested that the validity and utility of the affective process models need further investigation.     

Investment in Shared Suppliers: Effect of Learning,Spillover, and Competition

We investigate the optimal strategies for firms to invest in their suppliers when the benefits of such investments can spillover to other firms who also source from the same suppliers. We consider two Bayesian firms that can invest in improving the quality of their shared supplier; the firms do not have complete information on the true quality of the supplier, but they update their beliefs based on the supplier's performance. We formulate the problem as an investment game and obtain Markov perfect equilibria characterized by the investment thresholds of both firms. The equilibrium investment strategies of the two firms are characterized by a region of preemption and a region of war of attrition. We also examine how the interplay between spillover, competition, and returns from the investment at shared suppliers affect the investment threshold and the time to the leader's investment, and identify the conditions under which competition delays or hastens the first investment in a shared supplier.     

Factors Associated With Substance Use Disorders Among Traumatized Homeless Youth

This study aimed to identify homeless youths’ lifestyle and trauma-related risk factors as well as protective factors associated with alcohol use disorder or no disorder and drug use disorder or no disorder. Youth receiving homeless services in Denver (n = 201), Austin (n = 200), and Los Angeles (n = 200; N = 601) completed quantitative interviews assessing demographic information, alcohol and drug use, homeless lifestyle risk factors, trauma-related risk factors, and protective factors. Findings showed differences in trauma-related risk factors between alcohol and drug use disorders, but not homeless lifestyle risks. Protective factors predicted substance use disorders beyond risk factors. Understanding trauma-related risk and protective factors associated with substance use disorders could improve interventions.