Understanding preferences for tree attributes: the relative effects of socio-economic and local environmental factors

Urban plant biodiversity is influenced by both the physical environment and attitudes and preferences of urban residents for specific plant types. Urban residents are assumed to be disconnected from their immediate environment, and cultural and societal factors have been emphasized over environmental factors in studies of landscaping choices. However, we postulate that local climatic and environmental factors can also affect preferences for plant attributes. Therefore, spatial and temporal patterns in urban tree biodiversity may be driven not only by the direct effect of environmental variables on plant function, but also by the effect of environmental variables on attitudes toward trees and associated choices about which types of trees to plant. Here, we tested the relative effects of socio-economic and local environmental factors on preferences toward tree attributes in five counties in southern California in and surrounding Los Angeles, based on 1,029 household surveys. We found that local environmental factors have as strong an effect on preferences for tree attributes as socio-economic factors. Specifically, people located in hotter climates (average maximum temperature 25.1 °C) were more likely to value shade trees than those located in cooler regions (23.1 °C). Additionally, people located in desert areas were less likely to consider trees to be important in their city compared with people located in naturally forested areas. Overall, our research demonstrates the inherent connections between local environmental factors and perceptions of nature, even in large modern cities. Accounting for these factors can contribute to the growing interest in understanding patterns of urban biodiversity.     

Durkheim and pierce on suicide and economic change

This paper is an attempt to build upon Pierce's important finding, a confirmation of Durkheim, that any form of economic disruption or change increases suicide. In this paper, certain aspects of Pierce's method are criticized. The analysis of an expanded and updated data set, using analytic techniques designed for time-series data, suggests that economic disruption per se is not as relevant to the suicide rate as are economic hardship and economic deterioration or improvement.     

Hopes and Fears: the Conflicting Effects of Risk Ambiguity

The Ellsberg Paradox documented the aversion to ambiguity in the probability of winning a prize. Using an original sample of 266 business owners and managers facing risks from climate change, this paper documents the presence of departures from rationality in both directions. Both ambiguity-seeking behavior and ambiguity-averse behavior are evident. People exhibit fear effects of ambiguity for small probabilities of suffering a loss and hope effects for large probabilities. Estimates of the crossover point from ambiguity aversion (fear) to ambiguity seeking (hope) place this value between 0.3 and 0.7 for the risk per decade lotteries considered, with empirical estimates indicating a crossover mean risk of about 0.5. Attitudes toward the degree of ambiguity also reverse at the crossover point.     

Discount rates and risky sexual behaviors among teenagers and young adults

This article examines the relationship between personal discount rates and sexual behaviors in a sample of teenagers and young adults. We find that higher discount rates (an indication of less willingness to forego current consumption for future consumption) are significantly associated with a range of sexual behaviors, including ever having sex, having sex before age 16 years, and past or current pregnancy. These associations are consistent with previous studies showing a link between discounting and other, non-sexual health behaviors. JEL Classification D80 · D90 · I10     

Strategic and Sincere Voting in a One‐Sided Election: The Canadian Federal Election of 1997*

Objective. We are interested in whether and how voters make strategic decisions in a race that is, according to the polls, expected to be very one sided. Looking specifically at the choices available to ideologically right‐of‐center voters in the 1997 Canadian federal election, we argue that strategic considerations will be filtered by voters' assessments of the competitiveness of the race both locally and nationally. Methods. We estimate logistic regression models measuring support for the two right‐of‐center Canadian political parties. Our models focus on the relationship between assessments of district‐ and national‐level party prospects on voting for the Progressive Conservative Party. Results. We find that voters who consider the race competitive emphasize district‐level data in their strategic calculations. However, those who consider the election to be all but over look more closely at national‐level concerns when deciding which right‐wing party to support. Conclusions. We conclude that earlier understandings of tactical voting should be updated to take into consideration the circumstances under which voters will use national‐level evaluations of relative party viability in casting their ballots.     

Altruism,the free rider problem and group size

This paper is a survey of recent theoretical work on the influence of group size, perceived effectiveness or noticeability of one's behavior on a group member's altruistic responses. Experiments on this problem are analyzed and evaluated, and problems for future research are outlined.This paper is a revised version of a paper originally presented at the March 1973 meetings of the Public Choice Society. In preparing this paper I have benefited from criticisms and suggestions made by a number of people and I wish to take this opportunity to thank them. Among them are John Bonin, Barry Groffman, Bob O'Gorman, Don Moon, George Reynolds and Harrison Wagner.