An Alternative Theoretical Explanation and Empirical Insights into Overordering Behavior in Supply Chains*

The beer game and the supply line underweighting theory are central to our knowledge of decision making in dynamic environments such as supply chains. The core of these theories is that people are incapable of recognizing the pipeline inventory and this is the main cause of overordering and dysfunctional behavior. This article identifies lacunae in the theoretical and empirical foundations of extant literature and proposes an alternate explanation, a “correction model,” explaining why overreactions occur. We adopt a multi‐method research design, comprising a field case study and laboratory experiments, to ground our findings. [Submitted: July 19, 2010. Revisions received: December 8, 2010; March 14, 2011. Accepted: March 28, 2011.]     

Maternal Hurricane Exposure and Fetal Distress Risk

Logistic regression and spatial analytic techniques are used to model fetal distress risk as a function of maternal exposure to Hurricane Andrew. First, monthly time series compare the proportion of infants born distressed in hurricane affected and unaffected areas. Second, resident births are analyzed in Miami‐Dade and Broward counties, before, during, and after Hurricane Andrew. Third, resident births are analyzed in all Florida locales with 100,000 or more persons, comparing exposed and unexposed gravid females. Fourth, resident births are analyzed along Hurricane Andrew's path from southern Florida to northeast Mississippi. Results show that fetal distress risk increases significantly with maternal exposure to Hurricane Andrew in second and third trimesters, adjusting for known risk factors. Distress risk also correlates with the destructive path of Hurricane Andrew, with higher incidences of fetal distress found in areas of highest exposure intensity. Hurricane exposed African‐American mothers were more likely to birth distressed infants. The policy implications of in utero costs of natural disaster exposure are discussed.     

Redescending M-estimators

In finite sample studies redescending M-estimators outperform bounded M-estimators (see for example, Andrews et al. [1972. Robust Estimates of Location. Princeton University Press, Princeton]). Even though redescenders arise naturally out of the maximum likelihood approach if one uses very heavy-tailed models, the commonly used redescenders have been derived from purely heuristic considerations. Using a recent approach proposed by Shurygin, we study the optimality of redescending M-estimators. We show that redescending M-estimator can be designed by applying a global minimax criterion to locally robust estimators, namely maximizing over a class of densities the minimum variance sensitivity over a class of estimators. As a particular result, we prove that Smith's estimator, which is a compromise between Huber's skipped mean and Tukey's biweight, provides a guaranteed level of an estimator's variance sensitivity over the class of densities with a bounded variance.     

Legitimacy of tolerating limited environmental pollution? The case for natural attenuation

Degradations of environmental quality often pose severe harms or at least adverse effects to individuals and societies. Perceiving any environmental pollution thus appears to be connected with an implicit claim for its prompt and complete removal. For example, the oil-spill from the "Prestige" accident at the western Spanish shoreline is surely still in everyone's mind, where—in a somewhat Sysiphos-effort—a lot of helpers tried to remove the huge masses of oil mud, washed repeatedly ashore. However, alternative rehabilitation conceptions are also conceivable for certain pollution problems, which may be less unhealthy and possibly more efficient. Among them, taking advantage of natural occurring processes, which are grouped in this context as "natural attenuation" (NA), is an emerging and challenging but possibly also a questionable approach. NA as remediation strategy is, therefore, often discussed controversially among experts and actors as well as in the public (Teutsch/Rügner 2000). This is partly due to still open scientific or technical questions but also due to legitimacy problems of natural attenuation on ethical and juridical levels (Steffens et al. 2002; Heinz 2002). Therefore, a balanced view on adequate natural attenuation seems to be necessary. The following analysis will review NA as rehabilitation means from the normative perspective, giving some general statements—and thus orientation—for public policy making as well as for the administrative level.     

Robust binary regression

Robust procedures increase the reliability of the results of a data analysis. We studied such a robust procedure for binary regression models based on the criterion of least absolute deviation. The resulting estimating equation consists in a simple modification of the familiar maximum likelihood equation. This estimator is easy to compute with existing computational procedures and gives a high degree of protection.     

An Application of Partial Least Squares to the Construction of the Social Institutions and Gender Index (SIGI) and the Corruption Perception Index (CPI)

This paper discusses households’ food insecurity among low income, poor urban households in and around the City of Tshwane, South Africa’s capital city. Using systematic random sampling with sampling interval of three, primary data were collected from 900 selected households, though only data from 827 households were analyzed following a rigorous coherence tests. The survey was conducted in Attridgeville, Soshanguve, and Tembisa. In the process, the study employed the use of two-way analyses of variance to explain differences between actual and expected household food security perceptions and those of severe, moderate and mild food insecurity. A favourable (adverse) variance could be interpreted to imply that means for achieving household food security are lower (higher) than predicted or that food security is higher (lower) than expected given the same level of main determinants. The observed variance is partitioned into components attributable to different sources of variation. ANOVA provides a statistical test of whether or not the means of several groups experiencing favourable (adverse) variances are equal. The main findings are that variances in the population means of households’ experiences of food insecurity vary by income class of the head of household, engagement in formal or informal income sources and by categories of social grants received. Poorer households that depend largely on cash income for food purchases experience highest food security variances and those receiving state pension. As such, timely receipt of household income under conditions of unimpeded access to social grants will improve urban poor households’ food security. The level of educational attainment has a very strong impact on a household’s food security. Those with “no schooling” have the lowest level of food security. Experiencing high variances in access to child grants, and low incomes, younger female household heads experience the highest degree of variances in food security and should be particularly targeted in an effective food security policy plan. Negative food security variance among these categories of South Africans could be devastating.     

Comparing the transpirational and shading effects of two contrasting urban tree species

Urban Ecosystems - Urban trees are getting increasing attention as a tool to mitigate urban heat island effects. A more functional and quantitative view of transpirational and shading effect,...     

Quality of College Life (QCL) of Students: Further Validation of a Measure of Well-being

This paper reports a study designed to further validate a measure of quality of college life (QCL) of university students (Sirgy, Grzeskowiak, Rahtz, Soc Indic Res 80(2), 343–360, 2007). Two studies were conducted: a replication study and an extension study. The replication study involved surveys of 10 different college campuses in different countries. The results of the replication study provided additional nomological (predictive) validation support of the measure based on a theoretical model mapping out the antecedents and consequences of satisfaction with college life. With respect to the extension study, the focus was to further test the nomological validity of the QCL measure by arguing and empirically demonstrating that the consequence of QCL is life satisfaction. The extension study involved a survey of three college campuses in different countries. The results were also supportive of the nomological validity of the QCL measure.