An investigation of transformation-based prediction interval for the Weibull median life

Statistical inference based on the Weibull distribution, a distribution widely used in reliability and survival analysis, is usually difficult as it often involves numerical computation and approximation. However, this distribution can be transformed to near-normality by a simple power transformation. Based on this transformation, a prediction interval (PI) for its median can be easily constructed through an inverse transformation. The procedure for selecting the best power transformation through minimizing Kullback-Leibler information is described. The property of this transformation-based PI is investigated. Simple correction factors are also proposed. It is shown that the transformation-based PI with corrections performs well, irrespective of the sample size and parameter values. Simulation results show that the new PI generally outperforms the existing PI. Numerical examples are given for illustration.     

信息不对称在农业保险中的表现极其防范

信息不对称严重阻碍了农业保险的健康发展，建议通过建立克服农业保险中信息不对称的有效体系，以促进我国农业保险的健康发展。     

相互制农业保险在我国的困境及适用性

相互制保险在农业保险领域有着明显的优势。然而,相互制保险管理制度上的缺陷及其与农业保险的矛盾制约着相互制农业保险的发展。目前,在我国合作意识不强、农村合作经济组织发育不健全的情况下,开展相互制农业保险还有一定困难。因此,要开展相互制农业保险,必须选择合适的范围和地区,并对相互制保险进行制度创新,为相互制农业保险提供财政补贴,建立再保险机制,加强引导,减少行政干预。     

中国寿险需求实证分析

本文对国内外的寿险需求分析研究进行了简单综述，在此基础上抽取全目30省市1998—2003年的数据．采取面板数据模型就收入、通货膨胀、社会保障、银行利率、死亡率等寿险需求影响因素与保费收入相关性作了Granger因果性检验分析。     

全球视野下中国保险业的发展趋势

中国保险市场是全球最重要的新兴保险市场之一,在经济全球化背景下,国际保险业发展的新趋势将对中国保险业的发展产生重大而深远的影响,中国保险业在经营理念、发展模式、扩张路径和运营模式等方面将发生深刻的变革。     

The Workout of Banking Crises: A Macroeconomic Perspective

This paper provides a macroeconomic perspective for governmentinterventions in banking crisis. Such crisis occur when a largenumber of banks fail to meet capital requirements or are insolvent.Using a macroeconomic model with financial intermediation, ouranalyis suggests that strict enforcement of capital-adequaterules suffices in prosperous periods. Capital requirements serveas an indicator for crises interventions in critical stateswhich may require interest rate intervention and restructuringof the banking industry. These policies can be reinforced byrandom bailouts and temporary financial relief, with a largepercentage of the costs being covered by current and futureowners of banks. (JEL D41, E4, G2)     

Modeling Conditional Yield Densities

Given the increasing interest in agricultural risk, many have sought improved methods to characterize conditional crop-yield densities. While most have postulated the Beta as a flexible alternative to the Normal, others have chosen nonparametric methods. Unfortunately, yield data tends not to be sufficiently abundant to invalidate many reasonable parametric models. This is problematic because conclusions from economic analyses, which require estimated conditional yield densities, tend not to be invariant to the modeling assumption. We propose a semiparametric estimator that, because of its theoretical properties and our simulation results, enables one to empirically proceed with a higher degree of confidence.     

Economic analysis of the impact of adopting herd health control programs on smallholder dairy farms in Central Thailand

The economic impact of adopting herd health programs for mastitis and reproduction by small-scale dairy producers of Central Thailand was assessed using a policy analysis matrix (PAM). Following a reduction in the incidence of bovine disease on adopter farms, an increase in private net profits is observed. More importantly the social costs of supporting dairy farmers is reduced; the PAM effective protection coefficient was reduced by 35% for mastitis program adopters and by 44% for reproductive program adopters, indicating improved social efficiency of dairy policy. Other indicators of efficiency and policy implications are discussed.     

Quality Competition and Social Welfare in Markets with Partial Coverage: New Results*

We use a vertical product differentiation model under partial market coverage to study the social welfare optimum and duopoly equilibrium when convex costs of quality provision are either fixed or variable in terms of production. We show the following new results. First, under fixed costs, the social planner charges a uniform price for the single variant that just covers costs of quality provision. Like the duopoly equilibrium, this socially optimal pricing entails a partially uncovered market, but a smaller share of the market is served compared with the duopoly equilibrium. Second, for the variable cost case, it is socially optimal to provide both high‐ and low‐quality variants, but market shares need not be equal. This differs from the result in fully covered markets. Third, in the duopoly equilibrium, the quality spread is too wide under variable costs relative to the social optimum. Under fixed costs, the duopoly produces two variants, but quality is too low relative to the social optimum, which has only one variant.