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.     

Learning from a lot: Empirical Bayes for high‐dimensional model‐based prediction

Empirical Bayes is a versatile approach to “learn from a lot” in two ways: first, from a large number of variables and, second, from a potentially large amount of prior information, for example, stored in public repositories. We review applications of a variety of empirical Bayes methods to several well‐known model‐based prediction methods, including penalized regression, linear discriminant analysis, and Bayesian models with sparse or dense priors. We discuss “formal” empirical Bayes methods that maximize the marginal likelihood but also more informal approaches based on other data summaries. We contrast empirical Bayes to cross‐validation and full Bayes and discuss hybrid approaches. To study the relation between the quality of an empirical Bayes estimator and p, the number of variables, we consider a simple empirical Bayes estimator in a linear model setting. We argue that empirical Bayes is particularly useful when the prior contains multiple parameters, which model a priori information on variables termed “co‐data”. In particular, we present two novel examples that allow for co‐data: first, a Bayesian spike‐and‐slab setting that facilitates inclusion of multiple co‐data sources and types and, second, a hybrid empirical Bayes–full Bayes ridge regression approach for estimation of the posterior predictive interval.     

Inference and optimal design of multiple constant-stress testing for generalized half-normal distribution under type-II progressive censoring

The generalized half-normal (GHN) distribution and progressive type-II censoring are considered in this article for studying some statistical inferences of constant-stress accelerated life testing. The EM algorithm is considered to calculate the maximum likelihood estimates. Fisher information matrix is formed depending on the missing information law and it is utilized for structuring the asymptomatic confidence intervals. Further, interval estimation is discussed through bootstrap intervals. The Tierney and Kadane method, importance sampling procedure and Metropolis-Hastings algorithm are utilized to compute Bayesian estimates. Furthermore, predictive estimates for censored data and the related prediction intervals are obtained. We consider three optimality criteria to find out the optimal stress level. A real data set is used to illustrate the importance of GHN distribution as an alternative lifetime model for well-known distributions. Finally, a simulation study is provided with discussion.     

现代俄语口语中省略词的使用

口语是语言变化、发展的重要环节。口语中的诸多表现手段缺少不了省略词的使用，而省略词的使用恰恰迎合了现代各种语言发展、变化的一个共同趋势，即简化趋势。本文从四个方面对现代俄语口语中省略词的使用情况进行了详细阐述，揭示了其在使用过程中所产生的语义、语法、词汇、修辞等方面的特点。     

文言文的英译技巧--林语堂译《浮生六记》与马丁·路德翻译细则之碰撞

从分析林译《浮生六记》与马丁·路德的翻译细则的碰撞入手 ,指出了新世纪的中国译学应是求同性与存异性的统一 ,既要广泛地批判吸收世界各国的译学传统 ,同时又要积极保持并展示自己文化的独立性与深度     

经贸英语在中国加入WTO后的新趋势

经贸英语对我国的经济和对外贸易业务起了相当重要的作用。中国加入WTO后和在西部大开发的进程中,同世界各国的外贸业务更加频繁,国际贸易业务知识已渗入日常的商务活动之中,外贸活动对英语能力的要求必将刺激经贸荚语的进一步发展和普及。外贸函电中电子商务的普遍应用,商务活动中的信息高速公路,电脑购物、电子货币和智能卡等,使得经贸英语出现许多新的特点和新的优势。本文对这些特点和优势进行了探讨。     

重庆市都市区人中就业现状及变化趋势

都市区作为重庆经济的核心区域,随着经济的快速发展以及城市化进程的加快,正对人口产生巨大的聚集效应,而人口就业将成为一个十分突出的问题。因此,准确把握劳动力供求变动趋势十分重要。为此通过模型运算,对2000-2020年的都市区劳动年龄人口和劳动力的供求变动趋势进行了预测分析。     

中国旅游开发投融资实践及走向

中国旅游业正成为国民经济新兴产业,中国旅游业正经历由亚洲旅游大国向2020年成为世界旅游强国转变的艰难跨越。这一跨越需要巨大的旅游投资来推动和实现。     

"20世纪文艺复兴"的重要篇章--两次大战期间的美国小说思潮述评

两次世界大战期间的美国小说,成就尤显卓著.它作为综合体现美利坚民族文化意识的最重要文学样式,充分显示了美国文学的现代性、多样性和独创性,并从不同的侧面,反映了发达的资本主义社会背景下的各种冲突和矛盾,刻印着社会心理嬗变的轨迹.     

大跃进时期的“赶超”思潮

“大跃进”运动是探索中国社会主义道路中所经历的一场带有全局性失误的经济建设运动。当时，“赶超”思潮成为一股不可忽视的势头，逐渐由理性走向非理性，进而偏离常规的轨道。实践中，“赶超”之风愈演愈烈，最终走向极端。这场运动影响深远，教训深刻，时刻提醒人们不能重蹈覆辙，为我国在经济建设上提供了前车之鉴。尤其是对当前经济建设具有重要启示。