新基建发展对产业升级的影响机制研究

新基建作为现代化基础设施体系的重要组成部分，已经成为中国经济高质量发展的重要支撑。基于2015—2021年中国71个城市的面板数据，构建双向固定效应、中介效应和调节效应三种回归模型，实证检验新基建发展对城市产业结构水平的影响及内在机制。研究发现：新基建发展能促进产业高级化水平，改善不合理的产业结构状态，提升产业合理化水平；新基建通过发展物联网和激励城市研发创新两种间接路径对产业结构转型升级产生积极影响；新基建对产业结构水平的影响受到地方政府干预行为的调节作用，在地方政府合理的行政管理下，新基建对产业转型升级的积极作用更为明显；新基建发展对产业结构水平的提升作用具有区域异质性和城市规模异质性，在中西部地区和大城市地区的作用效果更为明显。     

Trade liberalization and wage inequality: Evidence from Korea

This paper investigates the heterogeneous income distribution effects of trade liberalization using Korean survey data from years of 2000–2015. Following the Stolper-Samuelson theorem most of previous research studying the effects of trade liberalization on wage differences focus on workers’ characteristics (e.g., skilled or unskilled) while heterogeneity within the same worker group has not been yet substantially investigated. To fill this gap, this paper provides empirical evidence of wage inequality across firms within the same group of workers caused by trade liberalization, potentially implied in the new-new trade models with firm heterogeneity. Employing a difference-in-differences (DID) specification, we find that the wages of unskilled workers in Korea have increased since its FTAs with more advanced countries, such as members of EU and the US, came into effect, while the effects on the wages of skilled workers are negative but not statistically significant. We also show that wage effects are heterogeneous across firms within unskilled and skilled worker groups, while the positive effects are statistically significant and largest for unskilled workers in medium-large sized firms. These findings are in line with both traditional and new-new trade models.     

Factor Heterogeneity,Factor Market Imperfection and Trade

This paper develops a tractable model of examining how factor heterogeneity and imperfect factor market interact for determining a pattern of trade. Institution plays a crucial role for the interaction. In my work, firm productivity is defined as a composition of factor productivity and technology. Thus, input selection should affect the pattern of Melitz’s intra-industry allocation due to the incurring transaction cost. For a simple model, I assume two factors (labor and capital) and two sectors, which are relatively less institution-dependent and relatively more institution-dependent. When the economy is open, effect of the transaction cost on income distribution is more drastic for an institutionally underdeveloped country. Depending on institutional quality, the economic openness reallocates resource across countries through job creation or job destruction. The job turnovers redistribute income between heterogeneous labors within countries. The income redistribution is catalyzed by international mobility of capital. As a result, income disparity is widened between the institutionally developed country and the institutionally underdeveloped country. This paper can contribute to the literature of institution and international trade.     

《难经》压力波参数初探

根据压力波理论，分析了《难经》脉状的参数，演绎了主要参数的特征曲线，这对推进中医切诊医术的现代化具有现实意义。     

Determinants of Current Account Imbalances in 16 OECD Countries: An Out-Of-Sample Perspective

We employ panel data as well as country-specific models to uncover empirically the determinants of current account imbalances. We find evidence of slope heterogeneity likely rendering the fixed-effect estimator inconsistent. Mean group estimation is followed to overcome the latter difficulty. Both estimation techniques are evaluated by means of in- and out-of-sample criteria. The mean group estimator outperforms the fixed-effect approach and, moreover, only three economic variables are found to impact on the current account balance significantly. These are the government budget balance, the domestic output gap and the changes of the terms of trade. We finally propose a parsimonious dynamic model of the current account, including only these variables and illustrate that it has similar predictive accuracy as country-specific benchmark models. JEL no. F32, C23, C53     

Contemporary Extensions of the Rasch Model

This paper will introduce, discuss and illustrate two contemporary extensions of theRasch model: the one parameter logistic model (Verhelst and Glas, 1995) and theMultidimensional Rasch model (Hoijtink et al., 1999). Using data with respect tothe measurement of schizotypy (Vollema and Hoijtink, 2000) the most importantfeatures of both models will be illustrated. For the one parameter logistic modelthese include: a (discrete) discrimination parameter for each item; a test for itembias; and, estimation of the location of a person on the (latent) trait that is beingmeasured. For the multidimensional Rasch model these include: specification ofthe model; and, model selection. All analyses presented in this paper can be executedusing either OPLM (Verhelst et al., 1995), TESTFACT (Wilson et al.,1984) or ConQuest (Wu et al., 1998). At the end of the paper some features ofmodels and software that have not been discussed will be summarized.     

Forecasting economic time series using flexible versus fixed specification and linear versus nonlinear econometric models

Nine macroeconomic variables are forecast in a real-time scenario using a variety of flexible specification, fixed specification, linear, and nonlinear econometric models. All models are allowed to evolve through time, and our analysis focuses on model selection and performance. In the context of real-time forecasts, flexible specification models (including linear autoregressive models with exogenous variables and nonlinear artificial neural networks) appear to offer a useful and viable alternative to less flexible fixed specification linear models for a subset of the economic variables which we examine, particularly at forecast horizons greater than 1-step ahead. We speculate that one reason for this result is that the economy is evolving (rather slowly) over time. This feature cannot easily be captured by fixed specification linear models, however, and manifests itself in the form of evolving coefficient estimates. We also provide additional evidence supporting the claim that models which ‘win’ based on one model selection criterion (say a squared error measure) do not necessarily win when an alternative selection criterion is used (say a confusion rate measure), thus highlighting the importance of the particular cost function which is used by forecasters and ‘end-users’ to evaluate their models. A wide variety of different model selection criteria and statistical tests are used to illustrate our findings.     

结构异质性对中国能源高质量发展的影响研究

基于结构异质性对能源高质量发展影响的理论分析,使用稀疏主成分分析方法测度中国能源高质量发展水平,构建中国和八大经济区域面板分位数回归模型,实证研究了结构异质性对中国能源高质量发展的影响。结果表明：2003—2020年中国能源高质量发展水平有所提升,但仍存在明显的区域发展不平衡问题,西部地区和北部沿海地区的能源高质量发展水平更高。产业结构与能源高质量发展水平呈负相关关系,能源消费结构、资本配置结构与能源高质量发展水平呈正相关关系。     

考虑社会责任的异质有限理性制造商产量博弈均衡复杂动力学分析

通过考虑消费者剩余,企业利润中引入承担社会责任参数,建立了具有异质性有限理性的古诺寡头博弈竞争模型,分析利润相关参数对系统博弈均衡稳定性的影响,并进行了数值模拟。研究表明单方有限理性系统比双方有限理性系统稳定。产品成本超过一定阈值应避免产量竞争,可以通过承担社会责任,提升产品价格来增加利润,但当企业承担社会责任增加时,系统稳定性降低。此时降低调整产量的速度,观察竞争对手产量调整速度,避免系统进入混沌状态,失去最优产量优势。