Information provision and consumer search behavior for products with asymmetric uncertainty

When selling multiple products with asymmetric uncertainty, should the seller disclose product information so that customers do not have to incur any cost to resolve their uncertainties; if so, which product should the seller choose? To address these questions, we consider a monopolist selling two substitutable products to a group of consumers. Each consumer has asymmetric uncertainty regarding the two products. A total of four different information provision structures are considered based on whether the seller discloses information about each product with the aim of determining which strategy provides the seller with the greatest revenue. We derive several interesting results. First, the optimal information provision strategy depends on the magnitude of uncertainty in relation to the product with lower uncertainty. Specifically, if the uncertainty regarding the product with lower uncertainty is sufficiently small, it is optimal for the seller to provide information about the product with higher uncertainty, otherwise, the seller should provide information about both products. Second, when only one product's information should be revealed, it is optimal for the seller to choose the product with higher uncertainty and charge a higher price. Third, withholding information on both products is never optimal for the seller. Finally, our main model is extended by examining the Mean-Preserving Spread setting, and the robustness of our main results is confirmed. Furthermore, we examine the situation in which a monopolist sells a single product with two main attributes. We find that each of the four information provision strategies can be optimal under various scenarios.     

Panel unit root tests under cross-sectional dependence

In this paper alternative approaches for testing the unit root hypothesis in panel data are considered. First, a robust version of the Dickey-Fuller t -statistic under contemporaneous correlated errors is suggested. Second, the GLS t -statistic is considered, which is based on the t -statistic of the transformed model. The asymptotic power of both tests is compared against a sequence of local alternatives. To adjust for short-run serial correlation of the errors, we propose a pre-whitening procedure that yields a test statistic with a standard normal limiting distribution as N and T tends to infinity. The test procedure is further generalized to accommodate individual specific intercepts or linear time trends. From our Monte Carlo simulations it turns out that the robust OLS t -statistic performs well with respect to size and power, whereas the GLS t -statistic may suffer from severe size distortions in small and moderate sample sizes. The tests are applied to test for a unit root in real exchange rates.     

改革以来中国农村发展地区差距分析

本文在扩展农业部门新古典经济增长模型的基础上,构建了基于农业生产率指数和农村地区劳动力就业结构的农村发展指标,以此来衡量农村发展水平及其变化状况.为了考察中国农村发展地区差距的变化趋势,我们采用面板数据单位根检验的不同方法对其收敛性进行了严格的计量检验.检验结果显示,在考虑了时间和省份特殊效应、序列相关等因素的影响后,中国各省农村发展差距以及东中西部地区农村发展的内部差距均存在条件性β收敛.     

中国房地产投资与经济增长的计量分析

近几年,中国房地产市场比较热,不断掀起投资的浪潮,中国的经济随之也较快地增长。但是金融危机席卷全球,对于2009年,中国的房地产投资与经济增长又如何呢？本文立足于现实情况,采集了15年的数据先对房地产投资和GDP进行组合预测,然后运用计量经济的相关知识对这十几年的数据进行定量分析,提出自己的见解,并展望未来。     

备考江苏省计算机等级考试（二级VFP）策略

以Visual FoxPro（VFP）程序设计为例,具体分析了江苏省计算机等级考试的特点和题型,在此基础上,阐述了考生备考的复习方略,考试技巧,以期对广大考生有所帮助。     

Flexible Fourier stationary test in purchasing power parity for African countries

This study applies stationary test with a Fourier function proposed by Enders and Lee (2004 Enders, W and Lee, J. 2004. Testing for a unit root with a nonlinear Fourier function, Tuscaloosa, AL, , USA: Working Paper, Department of Economics, Finance and Legal Studies, University of Alabama.  [Google Scholar], 2009 Enders, W and Lee, J. 2009. The flexible Fourier form and testing for unit roots: an example of the term structure of interest rates, Tuscaloosa, AL, , USA: Working Paper, Department of Economics, Finance and Legal Studies, University of Alabama.  [Google Scholar]) to test the validity of long run Purchasing Power Parity (PPP) to assess the nonstationary properties of the real exchange rate for 20 African countries. We find that our approximation has higher power to detect U shaped breaks and smooth breaks than linear method if the true data generating process of exchange rate is in fact a stationary nonlinear process. We examine the validity of PPP from the nonlinear point of view and provide robust evidence clearly indicate that PPP holds true for almost African countries. Our findings point out their exchange rate adjustment is mean reversion towards PPP equilibrium values in a nonlinear way.     

New evidence of regional income divergence in post-reform Russia

This article investigates regional income convergence in Russia during 2000–2008. We test the hypothesis in which income divergence across regions of the country should give place to income convergence as the country moves toward free market economy with strong market institutions. The study contributes to the existing literature by using the exponential smooth autoregressive Augmented Dickey–Fuller (ADF) unit root test in a panel setup, a novel econometric technique, which encompasses cross sectional dependence. Results show strong evidence of on-going regional income divergence in post-reform period.     

Did financial deregulation help consumers? Access to market-yield instruments

The maturity effect (ME) of futures prices postulated by Samuelson (1965) is re-examined using three nonparametric tests. The consistent entropy asymmetry test by Racine and Maasoumi (2007) indicates that variance is an appropriate risk or uncertainty measure for ME, and value-at-risk and expected shortfall are also adopted. The Kolmogorov–Smirnov dominance test and Wilcoxon rank sum and signed rank test are employed to rank the estimates of the three risk measures under a moving-window framework. The testing outcomes are contingent on futures type, testing method and risk measures. The testing outcomes show mild support for ME.     

Convergence,technological interdependence and spatial externalities: a spatial dynamic panel data analysis

This study adopts a spatial dynamic panel data approach and spatial quasi-maximum likelihood to re-estimate the speed of growth convergence in 91 countries based on technological interdependence and spatial externalities. We perform a conditional Lagrange multiplier test for spatial error dependence and find some differences to previous studies. First, the switch from a cross-sectional to a dynamic panel data framework enables the estimated rate of conditional convergence to be higher, more accurate and more appropriate for realistic and theoretical expectations. Second, the spatial Durbin model (SDM) is a general form of simplified model that considers spatial error correlation, and its likelihood ratio test for the theoretical model of ‘learning by doing’ effect provides further evidence. Finally, statistical tests find that spatial correlation not only occurs in each variable, but also appears in the error term. Thus, the SDM does not exist in the assumptions associated with the spatial error, which are not necessarily correct.     

Are house prices in South Africa really nonstationary? Evidence from SPSM-based panel KSS test with a Fourier function

This study applies the sequential panel selection method (SPSM) to investigate the time-series properties of provincial house prices for entire, large, medium and small middle-segments of South Africa. Quarterly time-series data were collected from nine provinces in South Africa for different house-size categories over the period of 1978.Q1 to 2012.Q4. Whereas other panel-based unit-root tests are joint tests of a unit root for all members of a panel and are incapable of determining the mix of integrated of order zero (I(0)) series and integrated of order one (I(1)) series in a panel setting, the SPSM proposed by Chortareas and Kapetanios (2009) can clearly identify how many and which series in the panel are stationary processes by classifying a whole panel into a group of stationary and nonstationary series. The empirical results from several panel-based, as well as standard pure time-series, unit-root tests, indicate that house prices for the nine provinces studied here are either stationary or nonstationary. However, results from the SPSM using the panel version of the Kapetanios et al. (KSS, 2003) test with a Fourier function unequivocally indicate that house prices are stationary for the nine provinces under study. Our test results have important economic and policy implications for South Africa.