半平面上有限级随机Dirichlet级数的增长性

证明了右半平面上有限级随机Dirichlet级数的增长性几乎必然与其在每条水平直线上的增长性相同。     

Subsampling Variance Estimation for Non-stationary Spatial Lattice Data

ABSTRACT.  Most proposed subsampling and resampling methods in the literature assume stationary data. In many empirical applications, however, the hypothesis of stationarity can easily be rejected. In this paper, we demonstrate that moment and variance estimators based on the subsampling methodology can also be employed for different types of non-stationarity data. Consistency of estimators are demonstrated under mild moment and mixing conditions. Rates of convergence are provided, giving guidance for the appropriate choice of subshape size. Results from a small simulation study on finite-sample properties are also reported.     

The number of records within a random interval of the current record value

LetX ₁,X ₂, … be a sequence of i.i.d. random variables with some continuous distribution functionF. LetX(n) be then-th record value associated with this sequence and μ _n ⁻ , μ _n ⁺ be the variables that count the number of record values belonging to the random intervals(f−(X(n)), X(n)), (X(n), f+(X(n))), wheref−, f+ are two continuous functions satisfyingf−(x)<x, f+(x)>x. Properties of μ _n ⁻ , μ _n ⁺ are studied in the present paper. Some statistical applications connected with these variables are also provided.     

Consistent deconvolution in density estimation

Suppose we have n observations from X = Y + Z, where Z is a noise component with known distribution, and Y has an unknown density f. When the characteristic function of Z is nonzero almost everywhere, we show that it is possible to construct a density estimate f_n such that for all f, Iim_n| |=0.     

Complete consistency for the estimator of nonparametric regression models based on extended negatively dependent errors

In this paper, we provide some exponential inequalities for extended negatively dependent (END) random variables. By using these exponential inequalities and the truncated method, we investigate the complete consistency for the estimator of nonparametric regression model based on END errors. As an application, the complete consistency for the nearest neighbour estimator is obtained.     

A multilevel model with autoregressive components for the analysis of tribal art prices

In this paper, we introduce a multilevel model specification with time-series components for the analysis of prices of artworks sold at auctions. Since auction data do not constitute a panel or a time series but are composed of repeated cross-sections, they require a specification with items at the first level nested in time-points. Our approach combines the flexibility of mixed effect models together with the predicting performance of time series as it allows to model the time dynamics directly. Model estimation is obtained by means of maximum likelihood through the expectation–maximization algorithm. The model is motivated by the analysis of the first database ethnic artworks sold in the most important auctions worldwide. The results show that the proposed specification improves considerably over classical proposals both in terms of fit and prediction.     

建构主义教学理念和教学模式

在新的教育背景下,建构主义理论综合了教育家们的研究成果,建立了完整的知识观、学习观、教学观和基本原则,设计了富有代表性的建构主义教学法的四个模式,并在各科的教学实践中被广泛学习和应用。     

父母的婚姻教育匹配与子女学业表现

本研究基于2015年中国教育追踪调查（CEPS）数据,以父母婚姻教育匹配构建的“新型家庭文化资本”为视角,探讨不同婚配模式下“共同养育联盟”的水平与新型家庭文化资本被激活的效率对子女学业表现影响的作用路径。研究表明,与低等教育同质婚家庭的子女相比,向上婚以及高等教育同质婚家庭的子女学业表现更好。其二,父母婚姻教育匹配对子女学业表现的影响存在教育差距效应,随着父母间教育跨层级的增加,向上婚家庭中子女学业表现的优势递增,向下婚家庭中子女学业表现的劣势进一步扩大。其三,父母婚姻教育匹配模式对学业的影响因子女性别而异,向上婚和高等教育同质婚减弱了男孩的学习劣势,向下婚扩大了男孩的学习劣势。最后,家庭中的共同养育联盟对子女学业表现的影响发挥了部分中介作用。向上婚家庭的父亲与母亲在教养分工中建立了更互补的关系,共同养育联盟水平较高,更有效地激活了新型家庭文化资本,促进子女的学业表现。“强强联合”的婚姻教育匹配虽然成为不平等再生产的“温床”,但是,通过建立高水平的共同养育联盟这一中介路径提高新型家庭文化资本被激活的效率,则可能减缓教育不平等的代际传递。     

Impact of the tariff concessions of the RCEP agreement on the structure and evolution mechanism of manufacturing trade networks

In the world’s largest free trade area, the Regional Comprehensive Economic Partnership (RCEP) agreement will gradually eliminate tariffs on over 90% of member countries’ goods over the next 36 years. We construct a tariff policy effects evaluation framework based on the complex network theory. In this framework, the standard Global Trade Analysis Project (GTAP) model is recursively extended to generate forecasted data of bilateral trade. Based on this, we model the RCEP manufacturing trade networks and analyze the response of its core–periphery structure to the tariff concessions. Then, we evaluate policy effects on the evolution of trade patterns based on motif analysis. Finally, we construct separable temporal exponential family random graph models (STERGM) to explore the influence path and degree of the new tariff agreement on the evolutionary mechanisms of trade networks.     

Effect of systematic sampling on arima models

Given a general homogeneous non-stationary autoregressive integrated moving average process ARIMA(p,d,q), the corresponding model for the subseries obtained by a systematic sampling is derived. The article then shows that the sampled subseries approaches approximately to an integrated moving average process IMA(d,l), l≤(d-l), regardless of the autoregressive and moving average structures in the original series. In particular, the sampled subseries from an ARIMA (p,l,q) process approaches approximately to a simple random walk model.