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Nomadism has received surprisingly little attention in the ecological literature, and further work in this area is needed. The results of Woinarski’s reanalysis of our research findings are broadly similar to our own, and they support our original interpretation. However, his presentation is confusing and difficult to interpret.We used an information-theoretic approach to multimodel selection. We a priori defined plausible candidate models relating the variables described in our original paper or Woinarski’s reanalysis to the phenomenon of nomadism. We tested models that investigate nomadism as a function of nectivory, granivory, diet diversity, mixed diet, distance to body mass aggregation edge, mass, interactions between distance to edge and nectivory, distance to edge and mass, mass and nectivory, or mass and the interaction of edge and nectivory. There is consistency in our results across all sets of models, suggesting that mass, distance to body mass aggregation (scale breaks), and diet (nectivory) are all important factors in determining nomadism. In no case was nectivory or any other diet variable supported in a single-variable model. Given the same data and similar results, we and Woinarski reach fundamentally different conclusions. Woinarski views nomadism as an easily understandable result given knowledge of the proper single mechanistic variable, and he discounts interactions with structural features of the landscape and scaling. We conclude that nomadism is a fundamentally complex phenomenon without a single source of causation, and that it is the interaction of species, species attributes, and landscapes that is responsible for nomadic behavior. [ABSTRACT FROM AUTHOR]

The number of studies examining racial and socioeconomic disparities in the geographic distribution of environmental hazards and locally unwanted land uses has grown considerably over the past decade. Most studies have found statistically significant racial and socioeconomic disparities associated with hazardous sites. However there is considerable variation in the magnitude of racial and socioeconomic disparities found; indeed, some studies have found none. Uncertainties also exist about the underlying causes of the disparities. Many of these uncertainties can be attributed to the failure of the most widely used method for assessing environmental disparities to adequately account for proximity between the hazard under investigation and nearby residential populations. In this article, we identify the reasons for and consequences of this failure and demonstrate ways of overcoming these shortcomings by using alternate, distance-based methods. Through the application of such methods, we show how assessments about the magnitude and causes of racial and socioeconomic disparities in the distribution of hazardous sites are changed. In addition to research on environmental inequality, we discuss how distance-based methods can be usefully applied to other areas of demographic research that explore the effects of neighborhood context on a range of social outcomes. [ABSTRACT FROM AUTHOR]