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Little Choice (little + choice)
Selected AbstractsCoefficient shifts in geographical ecology: an empirical evaluation of spatial and non-spatial regressionECOGRAPHY, Issue 2 2009L. Mauricio Bini A major focus of geographical ecology and macroecology is to understand the causes of spatially structured ecological patterns. However, achieving this understanding can be complicated when using multiple regression, because the relative importance of explanatory variables, as measured by regression coefficients, can shift depending on whether spatially explicit or non-spatial modeling is used. However, the extent to which coefficients may shift and why shifts occur are unclear. Here, we analyze the relationship between environmental predictors and the geographical distribution of species richness, body size, range size and abundance in 97 multi-factorial data sets. Our goal was to compare standardized partial regression coefficients of non-spatial ordinary least squares regressions (i.e. models fitted using ordinary least squares without taking autocorrelation into account; "OLS models" hereafter) and eight spatial methods to evaluate the frequency of coefficient shifts and identify characteristics of data that might predict when shifts are likely. We generated three metrics of coefficient shifts and eight characteristics of the data sets as predictors of shifts. Typical of ecological data, spatial autocorrelation in the residuals of OLS models was found in most data sets. The spatial models varied in the extent to which they minimized residual spatial autocorrelation. Patterns of coefficient shifts also varied among methods and datasets, although the magnitudes of shifts tended to be small in all cases. We were unable to identify strong predictors of shifts, including the levels of autocorrelation in either explanatory variables or model residuals. Thus, changes in coefficients between spatial and non-spatial methods depend on the method used and are largely idiosyncratic, making it difficult to predict when or why shifts occur. We conclude that the ecological importance of regression coefficients cannot be evaluated with confidence irrespective of whether spatially explicit modelling is used or not. Researchers may have little choice but to be more explicit about the uncertainty of models and more cautious in their interpretation. [source] The role of food standards in international trade: evidence from Brazilian beef exports to the EU market,JOURNAL OF INTERNATIONAL DEVELOPMENT, Issue 6 2007Luciana Marques Vieira Abstract The study reviews the literature on global chain governance and food standards to allow for an assessment of Brazilian beef exports to the European Union. The empirical approach employed is based on company case studies. The results suggest that the Brazilian beef chain has little choice but to adapt to market changes as standards evolve. Costs of compliance for meeting international food standards reduce Brazil's comparative advantage. At the same time, changes in the nature of demand have created the need for a more integrated supply chain in order to enhance confidence in Brazil's beef production and processing abroad. Copyright © 2007 John Wiley & Sons, Ltd. [source] Counterfactuals and the Study of the American PresidencyPRESIDENTIAL STUDIES QUARTERLY, Issue 2 2002Jeffrey M. Chwieroth King (1993) argues that with the small number of presidents available for study, presidency scholars cannot construct reliable causal inferences by employing the presidency as the unit of observation. He goes on to suggest that presidency scholars should abandon such research designs and search for ways to increase their number of observations. This article evaluates King's methodological prescription by examining the utility of counterfactuals for presidency scholars. Relying on recent scholarship on counterfactuals, the author argues that presidency scholars may be able to produce reliable causal inferences while continuing to rely on the presidency as the unit of observation. He goes on to specify the conditions under which counterfactuals may be useful and illustrate the application of this method by examining Woodrow Wilson's failed effort to secure ratification of the Versailles Treaty. The author concludes that if presidency scholars' research dictates relying on the president as the unit of observation, then they are left with little choice but to rely on this method to test their theories with an adequate degree of certainty. [source] THE MYTH OF SELF-CREATIONBRITISH JOURNAL OF PSYCHOTHERAPY, Issue 3 2001Sue Gerhardt ABSTRACT This paper situates a case history in the context of an emerging theoretical perspective, influenced by attachment research, that gives increasing weight to early real interactions. It suggests that the developing individual often has little choice in the kind of relational strategies that their early interactions unconsciously set up. The case history explores how this might have been the case for Marian, and asks to what extent such a patient can subsequently choose to modify her way of relating to others, as an act of selfcreation. It suggests that to a large extent this is determined by her current social context and the vicissitudes of a jointly created therapeutic relationship. [source] | ||||||||||