Socioeconomic and ecological perceptions and barriers to urban tree distribution and reforestation programs

Tree planting and reforestation initiatives in urban and peri-urban areas often use tree distribution or “giveaway” programs as a strategy to increase tree cover and subsequent benefits. However, the effectiveness of these programs in terms of increasing overall tree cover and providing benefits to low-income and disadvantaged communities has been little studied. We assess these programs by exploring community participation in, and barriers to, an urban tree distribution program in Fort Lauderdale, United States and the role socioeconomic background and tree functional types have on participation. We use a mixed-methods approach, panel data, choice experiments, and econometrics to quantitatively analyze respondent’s ranking of program options. High income, White respondents had the highest level of awareness and participation while low income, African Americans (AA) had the lowest level. Monetary rebates were perceived as positive and significant as the compensation value increased to US$8.00 - $12.00. Fruit-bearing and native tree functional types were more preferred than flowering or shade trees. Latinos, AA, and high income respondents preferred fruit trees, while White, high income preferred native trees. Overall, low income respondents perceived the greatest barriers towards participation. 20% of Broward County residents who participated in the survey were aware of the tree giveaway programs and 13% had previously participated. Findings indicate an adaptive governance mismatch between program objectives to equitably increase city tree cover via planting shade trees versus individual’s knowledge and preference for other tree types and functions. Results can be used for developing and evaluating reforestation initiatives to equitably increase tree cover and improve the governance of urban ecosystems.     

Modelling of socio-ecological connectivity. The rural-urban network in the surroundings of Madrid (Central Spain)

As most of Europe’s metropolitan landscapes grow, a change is occurring in their surrounding rural environment. The consequences thereof mainly involve losses of traditional land uses and changes in the socioecomic structures of the local population. The lack of coupling ‘urban society-countryside’ can be considered to constitute a driving force of this process. The present paper focuses upon the rural-urban network around the metropolis of Madrid (Central Spain). We developed a quantitative model to explain the socio-ecological rural-urban linkages, taking into account the influence of the metropolis in the network of neighbouring municipalities. The results show a rural landscape gradient ranging from silvo-pastoral to agricultural land uses and maintaining different interactions with the local socioeconomy. Urban-rural polarisation of the territory and accessibility to the metropolis are the main factors influencing the landscape dynamics. Territorial cohesion among municipalities and connectivity with the metropolis are factors determining the socio-ecological structure. The agricultural area presents good social cohesion, but a weak connection with the City. The silvo-pastoral landscape, on the contrary, maintains prominent links with the metropolis, but a non-significant interconnection between the small towns. The model tested constitutes a useful tool for analysing socio-ecological connectivity and for quantifying, designing and promoting territorial cohesion policies.     

Generalizing the Announced Price Increase Problem*

This paper generalizes the announced price increase problem to consider a variety of practical concerns arising out of applications ranging from foreign exchange fluctuations to upper limits on the purchase of discounted supermarket items. These include limitations on the amount that can be purchased at the old price and/or on the length of the grace period, within which buyers may take advantage of this lower price. These constraints give rise to 16 possible situations. For each situation purchasing and inventory decision rules are developed. A numerical example is discussed to highlight the main features of the models.     

Population aging and legal retirement age

This paper analyzes the effects of population aging on the preferred legal retirement age. What is revealed is the crucial role that the indirect ‘macro’ effects resulting from a change in the legal retirement age play in the optimal decision. Two social security systems are studied. Under a defined contribution scheme, aging lowers the preferred legal retirement age. However, under a defined pension scheme, the retirement age is delayed. This result shows the relevance of correctly choosing the parameter affected by the dependency ratio in the design of the social security programme.

An Experiment on Rational Insurance Decisions

We describe the results of an experiment on decision making in an insurance context. The experiment was designed to test for the underlying rationality of insurance consumers, where rationality is understood in usual economic terms. In particular, using expected utility as the preference function, we test for positive marginal utility, risk aversion, and decreasing absolute risk aversion, all of which are normal postulates for any microeconomic decision context under uncertainty or risk. We find that there the discrepancy from rational decision making increases with the sophistication of the rationality criteria, that irrationality concerning fair premium contracts is uncharacteristically high, and that the slope of absolute risk aversion seems to depend on the format of the insurance contract. This revised version was published online in June 2006 with corrections to the Cover Date.     

The effect of reparametrization on accelerated lifetime tests

Efficient reliability industrial experiments consist of submitting items to accelerated life tests. It is of interest to obtain measures of the realiability of the devices under the usual working conditions, represented here by the mean lifetime. A practical problem refers to the accuracy of interval estimation of the parameter of interest when the sample size is small or moderate. In this paper, we describe the effect of several reparametrizations on the accuracy of the interval estimation. We propose a reparametrization that leads to accuracy while allowing orthogonality between the parameters. The idea is to consider a logarithmic reparametrization on orthogonal parameters in order to have independent maximum likelihood estimates with good asymptotic normal approximation. The study is illustrated by a data set on an accelerated life test at pressurized containers of Kevlan/Epoxy 49.     

Analytical expressions for the average adjustment interval and mean squared deviation for bounded adjustment schemes

This paper presents analytical expressions for the average adjustment interval and the mean squared deviation from target of the “bounded adjustment” schemes of Box and Luceno (1997a) under the assumption that the disturbances are generated from a double-exponential distribution. The solutions obtained are very close to those computed numerically for normally distributed innovations. This not only demonstrates the robustness of the schemes to the distributional assumptions, but also provides new useful expressions for the average adjustment interval and mean squared deviation from target. Expressions for the characteristic and probability mass functions of the adjustment interval are also given.     

Testing multivariate uniformity: The distance‐to‐boundary method

Given a random sample taken on a compact domain S ? ^d, the authors propose a new method for testing the hypothesis of uniformity of the underlying distribution. The test statistic is based on the distance of every observation to the boundary of S. The proposed test has a number of interesting properties. In particular, it is feasible and particularly suitable for high dimensional data; it is distribution free for a wide range of choices of 5; it can be adapted to the case that the support of S is unknown; and it also allows for one‐sided versions. Moreover, the results suggest that, in some cases, this procedure does not suffer from the well‐known curse of dimensionality. The authors study the properties of this test from both a theoretical and practical point of view. In particular, an extensive Monte Carlo simulation study allows them to compare their methods with some alternative procedures. They conclude that the proposed test provides quite a satisfactory balance between power, computational simplicity, and adaptability to different dimensions and supports.