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991.
In hazard models, it is assumed that all heterogeneity is captured by a set of theoretically relevant covariates. In many applications however, there are ample reasons for unobserved heterogeneity due to omitted or unmeasured factors. If there is unmeasured frailty, the hazard will not only be a function of the covariates but also of the unmeasured frailty. This paper discusses the implications of unobserved heterogeneity on parameter estimates with application to the analysis of infant death on subsequent birth timing in Ghana and Kenya using DHS data. Using Lognormal Accelerated Failure Time models with and without frailty, we found that standard models that do not control for unobserved heterogeneity produced biased estimates by overstating the degree of positive dependence and underestimating the degree of negative dependence. The implications of the findings are discussed. 相似文献
992.
Abstract This paper presents a simple weighted goal programming model which can be used to predict the current allocation of agricultural enterprises in a particular geographical area. Moreover, it also shows how the approach proposed can be integrated into a multiobjective framework to measure the opportunity cost of maintaining the current situation in terms of several criteria relevant from a private and a public perspective. In this way, the opportunity cost of sustaining the current allocation of agricultural enterprises in the irrigated lands of Tauste (Spain) is assessed in terms of gross margin, employment, seasonal labour and water consumption. 相似文献
993.
J. C. Newby 《国际农业可持续发展杂志》2013,11(3):456-470
In the marginal, upland regions of the Philippines, soil erosion and poverty are significant problems. The Landcare Programme has sought to address these twin problems. We assess the economic impacts of the Landcare Programme in the Province of Bohol. We first explore whether the adoption of Landcare practices, particularly those of contour farming and tree planting, in a highly degraded landscape has resulted in improved livelihood outcomes for upland farming families. Second, we analyse the potential for the piecemeal adoption of these measures to deliver tangible benefits at the watershed scale. Finally, using a benefit–cost approach, these outcomes are compared with the costs of research and extension projects that have helped achieve them. We conclude that the net economic impact of the Landcare Programme in Bohol is positive, with the primary beneficiaries being the individual households that adopt the Landcare practices. These benefits are largely generated by productive opportunities that arise once the hillsides have been stabilized. Although the downstream impacts of land-use changes associated with the Landcare Programme are positive, they are of marginal economic importance. Hence, the focus and primary justification of the Landcare Programme should be on improving the productivity and livelihoods of upland farming households. 相似文献
994.
RAY C. FAIR 《Contemporary economic policy》2012,30(4):618-628
This paper uses a structural multi‐country macroeconometric model to estimate the size of the decrease in transfer payments (or tax expenditures) needed to stabilize the U.S. government debt/gross domestic product (GDP) ratio. It takes into account endogenous effects of changes in fiscal policy on the economy and in turn the effect of changes in the economy on the deficit. A base run is first obtained for the 2013:1–2022:4 period in which there are no major changes in U.S. fiscal policy. This results in an ever increasing debt/GDP ratio. Then transfer payments are decreased by an amount sufficient to stabilize the long‐run debt/GDP ratio. The results show that transfer payments need to be decreased by 2% of GDP from the base run, which over the 10 years is $3.2 trillion in 2005 dollars and $4.8 trillion in current dollars. The real output loss is 1.1% of baseline GDP. Monetary policy helps keep the loss down, but it is not powerful enough in the model to eliminate all of the loss. The estimates are robust to a base run with less inflation and to one with less expansion. (JEL E17) 相似文献
995.
ABSTRACTThis article investigates the impact of corporate governance on bank efficiency across a sample of 139 commercial banks from 17 countries of Central and Eastern Europe during the period 2005–2012. Data on governance characteristics are hand-collected from banks’ reports. The empirical findings indicate that implementing rigorous corporate governance structures is associated with higher costs for banks and a lower level of efficiency. However, during the crisis, a tight governance mechanism significantly increases banks’ cost and technical efficiencies. We also show that prudent risk management is associated with both higher cost and technical efficiency for more capitalized banks, while rigid supervisory boards are linked with greater technical efficiency for more capitalized banks. 相似文献
996.
We examined how and why trust between a subordinate and supervisor develops over time from the separate perspectives and experiences of both dyad partners. Integrating the literatures on trust, leader-member-exchange (LMX) and promotion regulatory focus (PRF), we test our model using longitudinal data from a Malaysian subsidiary of a U.S. headquartered corporation. Subordinate's trust in supervisor mediated between supervisor's PRF and subordinate's experience of LMX quality; supervisor's trust in subordinate mediated between subordinate's job performance and leader's experience of LMX quality. Findings are interpreted within the high power-distance, high collectivist, and high performance orientation of Malaysian culture. 相似文献
997.
Aimee Lee S. Houde Chris C. Wilson Bryan D. Neff 《Journal of Great Lakes research》2017,43(1):211-215
Economically and culturally important salmonid species often compete with Atlantic salmon (Salmo salar) released from stocking programs or that escaped during aquaculture production. Such competitive interactions may lower the individual fitness of these species by reducing survival and body growth. Here, we exposed juvenile brown trout (S. trutta), rainbow trout (Oncorhynchus mykiss), Chinook salmon (O. tshawytscha), and coho salmon (O. kisutch) to juvenile Atlantic salmon in artificial streams for 10 months. Survival and fitness-related traits of the four species were not negatively impacted by the presence of Atlantic salmon. The results suggest that brown trout and rainbow trout have better competitive abilities than Atlantic salmon, and that Chinook salmon and coho salmon have limited competitive interactions with Atlantic salmon. Although we discuss certain environmental conditions that can favor Atlantic salmon as a competitor at the juvenile life stage, Atlantic salmon may have little impact on the productivity of these four species. 相似文献
998.
This paper tests for beta-convergence and sigma-convergence in the corporate governance models, using a sample of corporate governance ratings for 198 European corporations listed on the FTSE Eurofirst 300 index. A piecewise linear regression is deployed to select a model and the Poisson pseudo-maximum likelihood estimator is also applied to estimate an exponential model. It concludes that there is statistical evidence of beta- and sigma-convergence within countries and the results suggest that institutional differences between countries are statistically relevant. 相似文献
999.
1000.