Browsing by Subject "MODELS"

Now showing 1 - 3 of 3

Open Access
Free-ranging livestock threaten the long-term survival of giant pandas
(Biological Conservation, 2017-12-01) Li, Binbin V; Pimm, Stuart L; Li, Sheng; Zhao, Lianjun; Luo, Chunping
© 2017 Elsevier Ltd China has implemented forest policies and expanded protected areas to halt deforestation and protect giant panda habitats. These policies simultaneously encouraged local communities to raise livestock that then freely range in forests. This grazing had unintended consequences. As an alternative livelihood, it has become the most prevalent human disturbance across the panda's range. How do free-ranging livestock impact giant panda habitats and what are the implications for future conservation and policy on a larger scale? We use Wanglang National Nature Reserve as a case study. It has seen a nine-fold livestock increase during past 15 years. We combined bamboo survey plots, GPS collar tracking, long-term monitoring, and species distribution modelling incorporating species interaction to understand the impacts across spatial and temporal scales. Our results showed that livestock, especially horses, lead to a significant reduction of bamboo biomass and regeneration. The most intensively used areas by livestock are in the valleys, which are also the areas that pandas prefer. Adding livestock presence to predictive models of the giant panda's distribution yielded a higher accuracy and suggested livestock reduce panda habitat by 34%. Pandas were driven out of the areas intensively used by livestock. We recommend the nature reserve carefully implement a livestock ban and prioritise removing horses because they cause the greater harm. To give up livestock, local communities prefer long-term subsidies or jobs to a one-time payment. Thus, we recommend the government provide payments for ecosystem services that create jobs in forest stewardship or tourism while reducing the number of domestic animals.
Open Access
Household Charitable Giving at the Intersection of Gender, Marital Status, and Religion
(Nonprofit and Voluntary Sector Quarterly, 2018-02) Eagle, D; Keister, LA; Read, JG
© 2017, © The Author(s) 2017. Past research reveals mixed results regarding the relationship between gender and charitable giving. We show gender plays a significant role in giving but only when considered alongside marital status and religion. Using the 2006 Portraits of American Life Study, we model a household’s propensity to give and the amount given. We extend past research by disaggregating unmarried households to look at divorced, widowed, and never-married households, and by including multiple religion measures. Results indicate households headed by never-married females have lower giving levels compared with those headed by divorced and widowed women. In households headed by single males, these differences are largely absent. Religious attendance has a stronger association with giving in male-headed households. The respondent’s gender is also related to the amount married households report giving to charity. Future research on giving should consider both gender and marital status to more fully capture increasing diversity in American families.
Open Access
Preference Heterogeneity in the Structural Estimation of Efficient Pigovian Incentives for Insecticide Spraying to Reduce Malaria
(Environmental and Resource Economics, 2017-01-18) Brown, ZS; Kramer, RA
This paper bridges the theoretical and empirical literatures on the role of preference heterogeneity in characterizing externalities related to disease transmission. We use a theoretical structure similar to locational sorting models, which characterize equilibria in terms of marginal individuals who are indifferent between locations. In our case, the ‘locations’ are binary, consisting of whether or not to take a discrete preventative action. Individual heterogeneity arises in this structure due to variation in the costs and disutility associated with prevention. We demonstrate application of this approach in the context of participation in insecticide-based indoor residual spraying programs for malaria control in northern Uganda. We identify the parameters of our theoretical model using a stated preference choice experiment combined with estimates from published epidemiological studies. The model implies that Pigovian subsidies for participation in this context should decrease household malaria risk by 19–25%. Our approach can be applied to other bioeconomic externalities with spillovers from discrete preventative actions, including agricultural pest management and the control of pest infestations and invasive species.