BOCOG's outsourcing contracts: The vendor's perspective

To date, most research on outsourcing is modeled from the client's perspective. In this paper, we approach the Beijing Organizing Committee for the Games of the XXIX Olympiad (BOCOG) outsourcing contracts from the vendors’ perspective. Since a vendor always has the option to accept or not accept an outsourcing contract, we use the theory of options to analyze the vendor's decision making, i.e., the trigger point, which coincides with the optimal profit level, of the vendor's decision to pursue an outsourcing contract. Numerical examples are presented to demonstrate the model and its potential benefits for vendors’ decision making.     

Some asymptotic properties of the circular median

In this article, the asymptotic distribution of the circular median is derived for symmetric distributions on the circle. Its asymptotic relative efficienty with respect to the mean direction and to an estimator proposed by Watson (1983) is then examined. Special attention is given to the cases where the underlying distribution is von Mises and contaminated von Mises. It is seen that the circular median can perform more efficiently than both estimators in presence of outliers.     

Does the transtheoretical model predict attrition in domestic violence treatment programs?

Attrition in intervention programs for domestically violent men is considered to be a serious and enduring problem. Researchers have found a number of sociodemographic variables that partially explain this phenomenon; however, models based on these variables have a limited predictive power. Scott (2004) argues that a firm theoretical base is needed in future investigations of the problem and suggests the use of the transtheoretical model of behavior change (TTM), which was found to predict dropout with accuracy in other areas of behavioral change. This study investigated the relationship between four TTM constructs (Stages of Change, Decisional Balance, Self-Efficacy, and Processes of Change) and premature termination with a sample of Canadian French-speaking men (N = 302) in five domestic violence treatment programs. Contrary to the initial hypotheses, the TTM constructs did not predict dropout. Discussion investigates how social desirability bias affects results being obtained by current TTM measures and whether more motivation to change at intake necessarily relates to involvement in treatment for longer periods of time.     

The Effect of Lead Time Uncertainty on Safety Stocks

The pressure to reduce inventory investments in supply chains has increased as competition expands and product variety grows. Managers are looking for areas they can improve to reduce inventories without hurting the level of service provided. Two areas that managers focus on are the reduction of the replenishment lead time from suppliers and the variability of this lead time. The normal approximation of lead time demand distribution indicates that both actions reduce inventories for cycle service levels above 50%. The normal approximation also indicates that reducing lead time variability tends to have a greater impact than reducing lead times, especially when lead time variability is large. We build on the work of Eppen and Martin (1988) to show that the conclusions from the normal approximation are flawed, especially in the range of service levels where most companies operate. We show the existence of a service‐level threshold greater than 50% below which reorder points increase with a decrease in lead time variability. Thus, for a firm operating just below this threshold, reducing lead times decreases reorder points, whereas reducing lead time variability increases reorder points. For firms operating at these service levels, decreasing lead time is the right lever if they want to cut inventories, not reducing lead time variability.     

Do you believe that others are more positional than you? Results from an empirical survey on positional concerns in France

We explore empirically the relevance of positional concerns in France. Unlike previous literature, we use two types of surveys, one addressed to a convenience sample, and the other to a random sample of French households living in the metropolitan area of Montpellier. Surveys are composed of a set of hypothetical questions related to several domains (income, education, vacation time, etc.). We also investigate whether individuals consider themselves more or less positional than others in society. Moreover, a set of variables that could potentially explain why people give positional answers is considered, such as being positional on a domain in which the individual excels. In addition to more conventional findings, we show that (i) the percentage of positional answers for each domain is about the same in the random and convenience samples, (ii) people consider others as more positional than themselves, and (iii) excelling in a given domain is not necessarily a good predictor of positional preferences in this domain.     

Does self-employment contribute to national happiness?

Recent studies showed that self-employment impacts individual happiness either positively or negatively. Rather than considering the happiness effects at the individual level, we assess whether self-employment effects spread and impact the domestic happiness beyond the involved individuals. We distinguish a direct effect of self-employment on life satisfaction and an indirect effect through the impact of self-employment on per capita income and the subsequent impact of income on life satisfaction. Using panel data analysis for 15 OECD countries over a period of 18 years, we investigate empirically whether countries with higher levels of self-employment are happier, by disentangling the two previously mentioned effects. We remedy the potential endogeneity problem when estimating the indirect effect by instrumenting the self-employment rate. The main finding is a significant and negative direct effect which is larger in magnitude than the indirect effect, resulting in an overall negative effect of self-employment on the domestic happiness.     

An omnibus test of goodness-of-fit for conditional distributions with applications to regression models

We introduce an omnibus goodness-of-fit test for statistical models for the conditional distribution of a random variable. In particular, this test is useful for assessing whether a regression model fits a data set on all its assumptions. The test is based on a generalization of the Cramér–von Mises statistic and involves a local polynomial estimator of the conditional distribution function. First, the uniform almost sure consistency of this estimator is established. Then, the asymptotic distribution of the test statistic is derived under the null hypothesis and under contiguous alternatives. The extension to the case where unknown parameters appear in the model is developed. A simulation study shows that the test has good power against some common departures encountered in regression models. Moreover, its power is comparable to that of other nonparametric tests designed to examine only specific departures.