The Economics of Commonly Owned Groundwater When User Demand Is Perfectly Inelastic

This paper provides a theoretical analysis of the common-pool resource dilemma in extracting nonrenewable groundwater resources when water demand is perfectly inelastic. It complements the existing theory of groundwater use, which assumes away the possibility of demand perfect inelasticity. Under perfectly inelastic water demand, the common-pool resource dilemma is by-passed if groundwater users are equally productive in water use. If they are not, a new type of inefficiency can arise due to the lack of a rationing mechanism on the basis of productivity. Our analysis suggests that groundwater management research should pay more attention to water demand elasticity and productivity heterogeneity.common-pool resources, groundwater extraction, groundwater management, groundwater use, irrigation water demand, optimal control, pumping externality, water demand elasticity, Resource /Energy Economics and Policy,

The Impact of Nonfarm Activities on Agricultural Productivity in Rural China

Although evidence abounds that the development of rural non-farm activities have increased rural household income and contributed to rural development, the underlying structure and mechanism of the linkage between agricultural productivity and non-farm activities is poorly understood. Using a unique panel dataset of Chinese villages, this article examines the mechanism by which non-farm activities influence agricultural productivity. I find that Chinese villages’ non-farm revenue has a significant positive effect on agricultural land productivity. Although non-farm activities do withdraw labor out of agriculture and therefore dampen land productivity, that negative effect is negligible in comparison with the land productivity improvement brought by nonfarm revenue-financed infrastructure capital investment.Rural non-farm activities, labor migration, agricultural productivity, infrastructure capital., Agricultural and Food Policy, Productivity Analysis, O13, Q18,

Fundamentals of the TianQin mission

This talk adds more detail to the proposed TianQin mission \cite{TQ}. The response of TianQin to a binary source is an important problem for the experiment. Here we present the detail of the response function of an equal-arm Michelson interferometer to the gravitation waves of a binary source with a circular orbit.Comment: To be published in the proceedings of the "XIIth International Conference on Gravitation, Astrophysics and Cosmology", (Moscow, Russia, 2015), World Scientific, Singapor

Pre-neutron-emission mass distributions for reaction 232^{232}Th(n, f) up to 60 MeV

The pre-neutron-emission mass distributions for reaction $^{232}$Th(n, f) up to 60 MeV are systematically studied with an empirical fission potential model. The energy dependences of the peaks and valleys of the pre-neutron-emission mass distributions are described by the exponential expressions based on the newly measured data. The energy dependence of evaporation neutrons before scission, which plays a crucial role for the reasonable description of the mass distribution, is also considered. Both the double-humped and triple-humped shape of the measured pre-neutron-emission mass distributions for reaction $^{232}$Th(n, f) are reasonably well reproduced at incident energies up to 60 MeV. The mass distributions at unmeasured energies and the critical energies at which the humped pre-neutron-emission mass distributions are transformed into each other are also predicted.Comment: 9 figur

Estimating the Spatial Distribution of Groundwater Demand In the Texas High Plains

Developing groundwater management plans requires a good understanding of the interdependence of groundwater hydrology and producer water use behavior. While state-of-the-art groundwater models require water demand data at highly disaggregated levels, the lack of producer water use data has held up the progress to meet that need. This paper proposes an econometric framework that links county-level crop acreage data to well-level hydrologic data to produce heterogeneous patterns of crop choice and irrigation practices within a county. Together with agronomic data on irrigation water requirements of various crops and irrigation practices, this model permits estimation of the water demand distribution within a county. We apply this model to a panel of 16 counties in the Southern Texas High Plains from 1972 to 2000. The results obtained not only are consistent with those from the traditional multinomial logit land use model, but also indicate the presence of large intra- and inter-county heterogeneity in producer water use behavior.Discrete Choice Model, Random-coefficients Discrete Choice Model, Crop Choice, BLP, Groundwater, Texas High Plains, Ogallala Aquifer, Crop Production/Industries, Resource /Energy Economics and Policy,

Adoption of Variability Detection and Variable Rate Application Technologies by Cotton Farmers in Southern United States

A nested logit model was used to analyze the 2009 Southern Cotton Precision Farming Survey to study the impact of farmer and farm characteristics on the adoption of Variability Detection Technologies (VDT) and the adoption of Variability Rate application Technology (VRT) conditioned on the type of the VDT chosen. The results showed that the farm size and exposure to extension activities are important factors affecting the choice of VDTs. The farmers adopting both soil and plant based VDTs are more likely to adopt VRT. The probability of adoption of VRTs was lower for Texas cotton farmers irrespective of the type of VDT adopted. In general, younger, more educated farmers who use computers for farming operations are more likely to adopt VRT when they choose soil based or both soil and plant based VDT.Precision Agriculture, Technology Adoption, Cotton, Crop Production/Industries, Farm Management, Research and Development/Tech Change/Emerging Technologies, O33, Q16,

Galaxy-galaxy weak-lensing measurement from SDSS: II. host halo properties of galaxy groups

As the second paper of a series on studying galaxy-galaxy lensing signals using the Sloan Digital Sky Survey Data Release 7 (SDSS DR7), we present our measurement and modelling of the lensing signals around groups of galaxies. We divide the groups into four halo mass bins, and measure the signals around four different halo-center tracers: brightest central galaxy (BCG), luminosity-weighted center, number-weighted center and X-ray peak position. For X-ray and SDSS DR7 cross identified groups, we further split the groups into low and high X-ray emission subsamples, both of which are assigned with two halo-center tracers, BCGs and X-ray peak positions. The galaxy-galaxy lensing signals show that BCGs, among the four candidates, are the best halo-center tracers. We model the lensing signals using a combination of four contributions: off-centered NFW host halo profile, sub-halo contribution, stellar contribution, and projected 2-halo term. We sample the posterior of 5 parameters i.e., halo mass, concentration, off-centering distance, sub halo mass, and fraction of subhalos via a MCMC package using the galaxy-galaxy lensing signals. After taking into account the sampling effects (e.g. Eddington bias), we found the best fit halo masses obtained from lensing signals are quite consistent with those obtained in the group catalog based on an abundance matching method, except in the lowest mass bin. Subject headings: (cosmology:) gravitational lensing, galaxies: clusters: generalComment: 12 pages, 7 figures, submitted to Ap