Optimal regime switching and threshold effects

We consider a general control problem with two types of optimal regime switch. The first one concerns technological and/or institutional regimes indexed by a finite number of discrete parameter values, and the second features regimes relying on given threshold values for given state variables. We propose a general optimal control framework allowing to derive the first-order optimality conditions and in particular to characterize the geometry of the shadow prices at optimal switching times (if any). We apply this new optimal control material to address the problem of the optimal management of natural resources under ecological irreversibility, and with the possibility to switch to a backstop technology.     

混合地理加权回归模型的拟合及相关性检验

利用两步估计方法对混合地理加权回归模型进行拟合,运用Moran's检验方法探索误差项的空间相关性。     

电力系统抗差状态估计研究

状态估计能高效地估计出电力系统最佳的运行状态。测试并比较了基于原对偶内点法的加权最小绝对值估计与基于牛顿法求解的二次-线性准则、加权最小二乘估计的估计精度与计算效率,由测试结果可知,加权最小二乘估计虽有较高的计算效率,但估计精度偏差,而加权最小绝对值估计有着较高的估计精度,但较低的计算效率也限制了其工程应用。     

Gender wage gap studies: consistency and decomposition

This paper reviews the empirical literature on the gender wage gap, with particular attention given to the identification of the key parameters in human capital wage regression models. This is of great importance in the literature for two main reasons. First, the main explanatory variables in the wage model, i.e., measures of work experience and time-out-of-work, are endogenous. As a result, applying traditional estimators may lead to inconsistent parameter estimates. Second, empirical evidence on the gender wage gap hinges on estimates of the parameters of interest. Accordingly, their economic meaning may be limited by restrictive assumptions included in wage models. This challenges both researchers and policymakers who require precise measures of the gender wage gap in order to create and enforce efficient equality policies. This paper is a substantially revised version of the first chapter of my thesis. I am grateful to Christian Dustmann and Wendy Carlin for their great support and comments. I also thank Bernd Fitzenberger, colleagues at the Norwegian School of Economics and Business Administration and IZA, and three anonymous referees for their helpful comments and suggestions.     

The determinants of commercial banking profitability in low-, middle-, and high-income countries

Using a broad bank-level dataset and the GMM estimator technique described by Arellano and Bover (1995), this paper analyses how bank-specific characteristics, macroeconomic variables, and industry-specific factors affect the profitability of 10,165 commercial banks across 118 countries over the period from 1998 to 2012. Grouping the countries according to three income levels, we show that the determinants of bank profitability included in our model can explain existing profitability differences among commercial banks in low-, middle-, and high-income countries. The profitability determinants vary quite widely across the different levels of income in terms of significance, sign and size of the effect. The level of income has thus an important impact on the determinants of bank profitability.     

Forecasting economic time series with unconditional time-varying variance

The classical forecasting theory of stationary time series exploits the second-order structure (variance, autocovariance, and spectral density) of an observed process in order to construct some prediction intervals. However, some economic time series show a time-varying unconditional second-order structure. This article focuses on a simple and meaningful model allowing this nonstationary behaviour. We show that this model satisfactorily explains the nonstationary behaviour of several economic data sets, among which are the U.S. stock returns and exchange rates. The question of how to forecast these processes is addressed and evaluated on the data sets.     

Monetary and fiscal policy interactions in the post-war U.S.

A New Keynesian model allowing for an active monetary and passive fiscal policy (AMPF) regime and a passive monetary and active fiscal policy (PMAF) regime is estimated to fit various U.S. samples from 1955 to 2007. The results show that data in the pre-Volcker periods strongly prefer an AMPF regime, even with a prior centered in the PMAF region. The estimation, however, is not very informative about whether the Federal Reserve's reaction to inflation is greater than one in the pre-Volcker period, because much lower values can still preserve determinacy under passive fiscal policy. In addition, whether a PMAF regime can generate consumption growth following a government spending increase depends on the degree of price stickiness. An income tax cut can yield an unusual negative labor response if monetary policy aggressively stabilizes output growth.     

Forecast combinations under structural break uncertainty

This paper proposes two new weighting schemes that average forecasts based on different estimation windows in order to account for possible structural change. The first scheme weights the forecasts according to the values of reversed ordered CUSUM (ROC) test statistics, while the second weighting method simply assigns heavier weights to forecasts that use more recent information. Simulation results show that, when structural breaks are present, forecasts based on the first weighting scheme outperform those based on a procedure that simply uses ROC tests to choose and forecast from a single post-break estimation window. Combination forecasts based on our second weighting scheme outperform equally weighted combination forecasts. An empirical application based on a NAIRU Phillips curve model for the G7 countries illustrates these findings, and also shows that combination forecasts can outperform the random walk forecasting model.     

浅谈水利水电工程概预算的编制与应用

本文详细介绍了水利水电工程概预算编制依据、步骤、注意事项,探讨了水利水电工程概预算编制过程中常见问题的分析处理。     

Threshold cointegration and nonlinear adjustment between goods and services inflation in the United States

In this paper, we model the long-run relationship between goods and services inflation for the United States over the period 1968:1–2003:3. Our empirical methodology makes use of recent developments on threshold cointegration that consider the possibility of a nonlinear relationship between the two inflation series. According to our results, the null hypothesis of linear cointegration would be rejected in favor of a two-regime threshold cointegration model. Consequently, we could expect a cointegrating relationship only when the divergence between services inflation and goods inflation is above the threshold point estimate.