THE DYNAMICS OF REINTRODUCING, SUPPLEMENTING AND CONTROLLING ENDANGERED PREDATOR POPULATIONS

A dynamic model is developed to analyze the reintroduction of endangered predators. Non-convexities and the conditions under which reintroduction is sub-optimal are studied. Following reintroduction, costly population control should be initiated before marginal animals impose net costs, providing an economic interpretation to changes in the sign of the shadow price.Environmental Economics and Policy,

Matching and Challenge Gifts to Charity: Evidence from Laboratory and Natural Field Experiments

This study designs a natural field experiment linked to a controlled laboratory experiment to examine the effectiveness of matching gifts and challenge gifts, two popular strategies used to secure a portion of the $200 billion annually given to charities. We find evidence that challenge gifts positively influence contributions in the field, but matching gifts do not. Methodologically, we find important similarities and dissimilarities between behavior in the lab and the field. Overall, our results have clear implications for fundraisers and provide avenues for future empirical and theoretical work on charitable giving.fundraising, threshold public goods, charitable giving, field experiments

VOLUNTARY REVELATION OF THE DEMAND FOR PUBLIC GOODS USING A PROVISION POINT MECHANISM

public goods, voluntary contributions, provision point, experiments, information, group size, Resource /Energy Economics and Policy, H41, C92,

Comparing opportunity cost measures of forest conservation in Uganda; implications for assessing the distributional impacts of forest management approaches

Reducing deforestation and forest degradation will mean imposing restrictions on the use of forest resources by households that currently use natural forests to maintain their livelihoods. An emerging issue in forest monitoring is the need to assess social and economic impacts in forest user communities of alternative policy and management approaches. Implicit but often unrecognized in forest management strategies focused on integrating people into forest management is that communities are not homogeneous , implying an important degree of variation in the costs of forest use restrictions across households. Quantitative economic methods are essential to a robust measurement of the real socio-economic impacts of forest management and conservation programs, and to adequately design compensation packages to offset local costs. A key entry point to understanding the scope of impact in design of a forest management program, under conditions of local subsistence use, is assessing the minimum compensation necessary to incentivize forest conservation. Two principal valuation approaches exist, financial and economic. The latter measures both financial and social values; but which approach should we use? The selection of valuation approach can dramatically impact estimates of the compensation required to affect real change in forest conservation. Empirical evidence on the divergence of different value measures are presented for four case study forests under different governance arrangements in Uganda. A contingent valuation (CV) survey was administered alongside a market price (MP) method household survey for park-adjacent households. In the CV survey respondents were asked to state their minimum level of compensation required to forgo access to timber and non-timber forest products from their local protected area for a period of one year, whilst the MP survey estimated total annual household income from all sources e.g. agriculture, livestock and forest access. Data were collected from households in areas adjacent to the forests according to a stratified random sample (n=690). Distributional differences in forest income and welfare values are examined, to illustrate the strengths and weaknesses of different valuation approaches for estimating the benefits of forest use. We find that a range of complimentary conclusions can be drawn from the two techniques. Together, they provide contrasting information on the importance of forest income to heterogeneous rural households and they can help assess the potential effectiveness of alternative forest management strategies and governance arrangements

Matching and Challenge Gifts to Charity:Evidence from Laboratory and Natural Field Experiments

This study designs a natural field experiment linked to a controlled laboratory experiment to examine the effectiveness of matching gifts and challenge gifts, two popular strategies used to secure a portion of the $200 billion annually given to charities. We find evidence that challenge gifts positively influence contributions in the field, but matching gifts do not. Methodologically, we find important similarities and dissimilarities between behavior in the lab and the field. Overall, our results have clear implications for fundraisers and provide avenues for future empirical and theoretical work on charitable giving.

Social Preferences and Voting: An Exploration Using a Novel Preference Revealing Mechanism

Public referenda are frequently used to determine the provision of public goods. As public programs have distributional consequences, a compelling question is what role if any social preferences have on voting behavior. This paper explores this issue using laboratory experiments wherein voting outcomes lead to a known distribution of net benefits across participants. Preferences are elicited using a novel Random Price Voting Mechanism (RPVM), which is a more parsimonious mechanism than dichotomous choice referenda, but gives consistent results. Results suggest that social preferences, in particular a social efficiency motive, lead to economically meaningful deviations from self-interested voting choices and increase the likelihood that welfare-enhancing programs are implemented.Institutional and Behavioral Economics, Research Methods/ Statistical Methods, C91, C92, D64, D72, H41,

ANOMALIES IN VOTING: AN EXPERIMENTAL ANALYSIS USING A NEW, DEMAND REVEALING (RANDOM PRICE VOTING) MECHANISM

This study investigates the influence of social preferences on voting decisions using a new Random Price Voting Mechanism (RPVM), which is best thought of as a public goods voting extension of the Becker-DeGroot-Marshack mechanism for private goods. In particular, this mechanism is used to investigate experimentally whether voting decisions are affected by the distribution of net benefits associated with a proposed public program. Recent papers have shown that, in additional to selfishness, factors such as inequality aversion, maximin preferences, and efficiency may influence individual decisions. However, the effect of social preferences on voting, the predominant funding mechanism for public goods by legislatures and public referenda, has not been thoroughly examined. We first establish the presence of anomalous behavior in dichotomous voting, and introduce the RPVM as a more efficient mechanism to examine such anomalies. We show that it is demand revealing in the presence of social preferences and empirically consistent with dichotomous choice voting. Laboratory experiments involving 440 subjects show that when net benefits are homogeneously distributed, the new RPVM is demand-revealing in both willingness-to-pay (WTP) and willingness-to-accept (WTA) settings, for both gains and losses. When the voting outcome potentially results in a heterogeneous distribution of (net) benefits, a systematic wedge appears between individuals' controlled induced values and their revealed WTP or WTA. With induced gains, the best-off subjects under-report their WTP and WTA in comparison to their induced value. Worst-off subjects express WTP and WTA that exceed their induced value. With induced losses a mirror image is evident. Best-off subjects over-report their induced value while the worst-off subjects under-report. Theoretical and econometric results presented in the paper suggest that these differences are caused by a concern for social efficiency.Institutional and Behavioral Economics,

Measuring the Local Opportunity Costs of Conservation: A Provision Point Mechanism for Willingness-to-Accept

Protected areas are employed world-wide as a means of conserving biodiversity. Unfortunately, restricting access to such areas imposes opportunity costs on local people who have traditionally relied on access to obtain resources such as fuelwood and bushmeat. We use contingent valuation to estimate the local benefits forgone from loss of access to a number of protected area types in Uganda. Methodologically, we innovate by implementing a "provision point" mechanism to estimate Willingness to Accept compensation (WTA) for loss of access to protected areas. We show that the provision point reduces mean WTA by a significant degree

Characterization of a plasminogen activator and its inhibitor in human mesangial cells

Characterization of a plasminogen activator and its inhibitor in human mesangial cells. In the course of some pathological and experimental nephropathies, intraglomerular fibrin deposits develop, possibly as a consequence of inefficient fibrinolysis. In vitro human glomeruli exhibit fibrinolytic activity due to the synthesis of plasminogen activators (PAs) such as, tissue-type PA (t-PA) and urokinase-type PA (u-PA). Immunofluorescence studies have previously shown that t-PA is localized in the capillary tufts and u-PA in the visceral epithelial cells. We have now investigated the fibrinolytic activity of cultured human mesangial cells. Inhibitory activity towards u-PA or t-PA but not plasmin was found in both conditioned medium and cellular extracts. Analysis of the conditioned medium by zymography revealed a single band of PA-activity (Mr: 110 to 120 kDa). Immunoneutralization with anti-t-PA and antiplasminogen activator inhibitor (PAI-1) IgG but not anti-u-PA or anti-PAI-2 removed this band. Reverse fibrin autography demonstrated the presence of PAI-1 in both cellular extracts and in conditioned medium. Western Blot analysis showed that two bands (50 kD and 120 kD) were recognized by the anti-PAI-1 antibody. By ELISA t-PA and PAI-1 antigens were found to increase progressively with time in the culture medium but not in cellular extracts. Both t-PA and PAI-1, but not u-PA and PAI-2, were also detected by immunofluorescence studies. Thus human glomerular mesangial cells synthesize and secrete t-PA and PAI-1 in vitro. PAI-1 is produced in excess, therefore t-PA is only found in the form of a complex with PAI-1