人民币汇率失衡及贸易壁垒对我国出口行业影响异质性研究

贸易摩擦、新冠疫情使我国经济贸易面临严峻挑战,人民币汇率波动及贸易壁垒将常态化地影响我国出口贸易.在加快形成以国内大循环为主体、国内国际双循环相互促进的新发展格局背景下,文章基于HS分类原则,选取WTO等机构的贸易数据,通过构建BEER模型测算了人民币汇率失衡程度;通过建立固定效应面板模型研究了人民币汇率失衡及贸易壁垒双因素对我国出口行业影响的异质性.研究表明:人民币汇率失衡对我国出口贸易整体上具有显著负向影响,非关税壁垒对我国出口贸易整体上具有显著正向影响;关税和非关税构成的贸易壁垒与人民币汇率失衡双因素对我国出口贸易具有显著抑制作用,并对不同出口行业的影响存在异质性;人民币汇率失衡与非关税壁垒双因素对大多行业均具有显著负向影响,人民币汇率失衡与关税壁垒双因素对不同行业影响的正负效应及程度大小有异质性.因此,建议通过运行逆周期因子等完善人民币汇率自我修正机制;通过引导出口企业了解使用外汇衍生品等促进外汇衍生品市场运行机制的健全;通过加强"海外仓"建设及深耕RCEP框架下的东盟十国市场等实施出口行业差异化贸易策略;通过提升自主科技创新能力等加快出口行业产业转型升级,推动双循环,实现我国出口贸易高质量发展.     

Towards Uniformly Efficient Trend Estimation Under Weak/Strong Correlation and Non‐stationary Volatility

In this paper, we consider the deterministic trend model where the error process is allowed to be weakly or strongly correlated and subject to non‐stationary volatility. Extant estimators of the trend coefficient are analysed. We find that under heteroskedasticity, the Cochrane–Orcutt‐type estimator (with some initial condition) could be less efficient than Ordinary Least Squares (OLS) when the process is highly persistent, whereas it is asymptotically equivalent to OLS when the process is less persistent. An efficient non‐parametrically weighted Cochrane–Orcutt‐type estimator is then proposed. The efficiency is uniform over weak or strong serial correlation and non‐stationary volatility of unknown form. The feasible estimator relies on non‐parametric estimation of the volatility function, and the asymptotic theory is provided. We use the data‐dependent smoothing bandwidth that can automatically adjust for the strength of non‐stationarity in volatilities. The implementation does not require pretesting persistence of the process or specification of non‐stationary volatility. Finite‐sample evaluation via simulations and an empirical application demonstrates the good performance of proposed estimators.     

高频数据瞬时波动率核估计的窗宽选择及算法研究

在瞬时波动率的各种估计量中，非参数估计量因其能准确地度量瞬时波动率，一直是学者们的研究热点。然而，这类估计量在实际应用中都面临着最优窗宽的确定问题。由于最优窗宽中往往携带一些难以估计的未知参数，使得在实际应用过程中确定最优窗宽的具体数值存在困难。本文以瞬时波动率的核估计量为例，借鉴非参数回归分析中窗宽选择的思想，构建了一种能从数据中准确计算出最优窗宽具体值的算法。理论的分析和数值上的验证表明：文中所构建的算法具有良好的稳定性、适应性和收敛速度。算法的提出为瞬时波动率的后续应用研究铺平道路。     

我国野生动植物进出口管理中存在的问题及解决途径

随着社会主义市场经济的发展，我国加入WTO后野生动植物进出口管理面临着一些新的挑战，存在的各种问题也越来越突出，已不能适应当前行政管理改革的要求。只有正确认识这些问题，从加强法制建设和改进行政管理两个方面采取积极的应对之策，才能促进我国野生动植物进出口管理的健康发展。     

寻求就业增长点

在扩大内需的过程中保障就业位置的增加 ,使就业增长速度与经济增长速度保持同步 ,这是我国目前经济工作面临的重要问题。为此 ,作者提出了增加就业位置和就业机会的几点看法。     

LOG-PERIODOGRAM ESTIMATION OF LONG MEMORY VOLATILITY DEPENDENCIES WITH CONDITIONALLY HEAVY TAILED RETURNS

Many recent papers have used semiparametric methods, especially the log-periodogram regression, to detect and estimate long memory in the volatility of asset returns. In these papers, the volatility is proxied by measures such as squared, log-squared, and absolute returns. While the evidence for the existence of long memory is strong using any of these measures, the actual long memory parameter estimates can be sensitive to which measure is used. In Monte-Carlo simulations, I find that if the data is conditionally leptokurtic, the log-periodogram regression estimator using squared returns has a large downward bias, which is avoided by using other volatility measures. In United States stock return data, I find that squared returns give much lower estimates of the long memory parameter than the alternative volatility measures, which is consistent with the simulation results. I conclude that researchers should avoid using the squared returns in the semiparametric estimation of long memory volatility dependencies.     

Refined Inference on Long Memory in Realized Volatility

There is an emerging consensus in empirical finance that realized volatility series typically display long range dependence with a memory parameter (d) around 0.4 (Andersen et al., 2001; Martens et al., 2004). The present article provides some illustrative analysis of how long memory may arise from the accumulative process underlying realized volatility. The article also uses results in Lieberman and Phillips (2004, 2005) to refine statistical inference about d by higher order theory. Standard asymptotic theory has an O(n^-1/2) error rate for error rejection probabilities, and the theory used here refines the approximation to an error rate of o(n^-1/2). The new formula is independent of unknown parameters, is simple to calculate and user-friendly. The method is applied to test whether the reported long memory parameter estimates of Andersen et al. (2001) and Martens et al. (2004) differ significantly from the lower boundary (d = 0.5) of nonstationary long memory, and generally confirms earlier findings.     

中韩出口产品的竞争程度分析

中国的出口将对周边国家包括韩国带来深远影响。中国和韩国的产品出口是否存在竞争关系,如何衡量中韩产品出口的竞争程度,是我们试图研究的主要问题。我们通过按技术构成对产品进行分类,并借鉴关志雄和Lall等人计算产品附加值的方法,比较分析了中国和韩国自20世纪80年代后期以来出口商品的结构变化。结果表明:中国和韩国的产业竞争程度并非表面显现的那么高,中国和韩国可以在国际分工的不同生产环节实现优势互补。     

HEAVY-TAILED-DISTRIBUTED THRESHOLD STOCHASTIC VOLATILITY MODELS IN FINANCIAL TIME SERIES

To capture mean and variance asymmetries and time‐varying volatility in financial time series, we generalize the threshold stochastic volatility (THSV) model and incorporate a heavy‐tailed error distribution. Unlike existing stochastic volatility models, this model simultaneously accounts for uncertainty in the unobserved threshold value and in the time‐delay parameter. Self‐exciting and exogenous threshold variables are considered to investigate the impact of a number of market news variables on volatility changes. Adopting a Bayesian approach, we use Markov chain Monte Carlo methods to estimate all unknown parameters and latent variables. A simulation experiment demonstrates good estimation performance for reasonable sample sizes. In a study of two international financial market indices, we consider two variants of the generalized THSV model, with US market news as the threshold variable. Finally, we compare models using Bayesian forecasting in a value‐at‐risk (VaR) study. The results show that our proposed model can generate more accurate VaR forecasts than can standard models.     

关于舟山外语复合型人才的开发与培养

在对舟山市外向型企业人才调研的基础上,就我国加入WTO后,根据舟山实际情况,探讨研究本市企业外语复合型人才开发与培养的问题,并对担负语言培训任务的浙江海洋学院外语专业的课程设置和课堂教学提出了改革意见,以求该专业毕业生尽快适应今后社会的需要。