Avian population dynamics and human induced change in an urban environment

The predominantly urban boroughs of Warrington and Halton straddle the river Mersey in northwest England. Since the 1970s there has been a major change in land-use associated with both innovative town design and the decline of manufacturing and chemical industries in the boroughs. Also, co-ordinated programmes have directly addressed air and water pollution. The breeding birds of the two boroughs were surveyed in 1978–84 and 2004–06 as part of the bird atlases of Cheshire and Wirral, based on tetrads (2 × 2 km squares). We divided the breeding species into eight guilds based on broad ecological characteristics of habitat or food, omitting the generalists and colonial species, and compared the change between our two atlases in the number of occupied tetrads in Halton and Warrington and in the rest of the county. Four of our eight guilds have fared significantly better within our study area: waterbirds (24 species), those feeding on invertebrates (16 species), woodland specialists (21 species) and the two species that decorate their nests with lichens. The remaining four guilds showed no difference between Halton and Warrington and the rest of Cheshire and Wirral: raptors (5 species) have increased throughout, while breeding waders (7 species), farmland seedeaters (7 species) and aerial insectivores (5 species) have declined throughout. We interpret these results in relation to improved quality of water and air and changing patterns of land-use in the urban greenspace, especially an increase in woodland cover and connectivity.     

Income management in Australia: A critical examination of the evidence

The introduction of income management – sometimes called welfare quarantining – for subgroups of Australian income security recipients within the Northern Territory, and subsequently a number of other trial sites, has provoked considerable contention. The present study critically examined the arguments and evidence presented in favour of income management with particular reference to the guidelines, methodology and findings of official evaluations conducted by the Commonwealth Government. We identified five key issues that do not seem to be adequately addressed by official evaluations: choice and control, the quality of decision making, consultation with local community members, structural disadvantage and economic cost. We used these concepts to develop a proposed alternative model for assessing the impact of income management on local communities.     

On the Existence of Monotone Pure‐Strategy Equilibria in Bayesian Games

We generalize Athey's (2001) and McAdams' (2003) results on the existence of monotone pure‐strategy equilibria in Bayesian games. We allow action spaces to be compact locally complete metric semilattices and type spaces to be partially ordered probability spaces. Our proof is based on contractibility rather than convexity of best‐reply sets. Several examples illustrate the scope of the result, including new applications to multi‐unit auctions with risk‐averse bidders.     

Consumer discrimination in the NBA: An examination of the effect of race on the value of basketball trading cards

In this research we use sport trading cards to examine consumer discrimination in the NBA. Using a Tobit analysis, we test whether the race of a player affects the value (price) of his NBA trading card. We find that a player's race does not affect the value of NBA trading cards. We conclude that some forms of consumer discrimination are declining in the NBA.     

A comparison study of nonparametric imputation methods

Consider estimation of a population mean of a response variable when the observations are missing at random with respect to the covariate. Two common approaches to imputing the missing values are the nonparametric regression weighting method and the Horvitz-Thompson (HT) inverse weighting approach. The regression approach includes the kernel regression imputation and the nearest neighbor imputation. The HT approach, employing inverse kernel-estimated weights, includes the basic estimator, the ratio estimator and the estimator using inverse kernel-weighted residuals. Asymptotic normality of the nearest neighbor imputation estimators is derived and compared to kernel regression imputation estimator under standard regularity conditions of the regression function and the missing pattern function. A comprehensive simulation study shows that the basic HT estimator is most sensitive to discontinuity in the missing data patterns, and the nearest neighbors estimators can be insensitive to missing data patterns unbalanced with respect to the distribution of the covariate. Empirical studies show that the nearest neighbor imputation method is most effective among these imputation methods for estimating a finite population mean and for classifying the species of the iris flower data.     

A Kantian-Style Critique of Person-in-Environment

This article provides a historical and philosophical analysis of the intellectual thought supporting ecological systems theory and the person-in-environment model. It offers a critique outlining both strengths and shortcomings by analyzing the claims to validity upon which the theory rests. These claims rest on an analogy with various theories empirically established in the natural sciences; as such, validity claims rest heavily upon the emphasis of humans' continuity with animals. Consequently, the claims' shortcomings arise from their inability to address adequately issues arising from qualities that make humans distinct from animals—such as language and its impact upon culture, history, human relationships, and our ability to construct our environment and thus do more than simply interact with the environment.