局部平稳部分线性面板数据模型的统计推断

部分线性模型是一类非常重要的半参数回归模型,由于它既含有参数部分又含有非参数部分,与常规的线性模型相比具有更强的适应性和解释能力。文章研究带有局部平稳协变量的固定效应部分线性面板数据模型的统计推断。首先提出一个两阶段估计方法得到模型中未知参数和非参数函数的估计,并证明估计量的渐近性质,然后运用不变原理构造出非参数函数的一致置信带,最后通过数值模拟研究和实例分析验证了该方法的有效性。     

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.     

Who cares? A lack of self‐care for women in the non‐profit/non‐governmental sector

In this article I examine the lack of self‐care regimes for women working in the non‐profit/non‐governmental sector. While I draw on ethnographic research conducted in the Malaysian context of women's organizations, the issue of self‐care for activists and feminist activists is a global one that crosses borders and boundaries. I explore the gendered nature of care and care professions to demonstrate how women are predominantly affected in these working environments. To date, there has been little scholarship on self‐care and care in non‐profit/non‐governmental working environments. Using interviews with women working in the sector, I argue that women's emotional, mental and physical health comes at a cost in these hectic workplaces. This article contributes to the literature on gender, work and care in women's organizations by taking seriously women's concerns working in these spaces, where they experience self‐neglect and institutional barriers in care regimes.     

Uniform consistency rate of kNN regression estimation for functional time series data

In this paper, we investigate the k-nearest neighbours (kNN) estimation of nonparametric regression model for strong mixing functional time series data. More precisely, we establish the uniform almost complete convergence rate of the kNN estimator under some mild conditions. Furthermore, a simulation study and an empirical application to the real data analysis of sea surface temperature (SST) are carried out to illustrate the finite sample performances and the usefulness of the kNN approach.     

虎鲨对温度、pH值的耐受性研究

本文报道了在LRH-250E型培养箱中对平均尾重0.2g和1.2g的虎鲨进行温度耐受性试验,并对均重1.2g的虎鲨做了pH耐受性研究。结果表明:尾重O.2g的虎鲨在驯化温度为20℃时,水温突变引起的致死高温为41℃,致死低温为14℃;尾重1.2g虎鲨在驯化温度为24℃时,水温突变引起的致死高温是42℃,致死低温为14.5℃。尾重1.2g虎鲨能够耐受的pH值其上限是11.51,下限是2.52。     

改革所有制结构 促进山西产业结构调整

公有制经济比例过大 ,非公有制经济比例过小是山西所有制结构存在的主要问题 ,它对山西产业结构的调整有着一定的制约作用。发展非公有制经济 ,适度压缩国有经济比例 ,是促进山西产业结构调整的重要举措之一。     

英语习语中的非言语交际表达

从跨文化交际的角度对英语习语中的非言语交际行为及其特征进行探讨研究,认为英语习语在非言语交际中具有民族性和修辞性的特征,通过身体动作、面部表情、颜色、服装容饰等非言语行为的表达,强调和加强了言语内容,使得习语更加形象、生动、传神。     

载体催化元件恒温检测甲烷浓度的研究

基于载体催化元件检测甲烷浓度的基本原理,提出了采用载体催化元件和参比元件组成惠斯登测量电桥,运用温度自动控制系统达到恒定甲烷无焰燃烧温度,实现甲烷浓度的测量。扩展了采用载体催化元件测量甲烷浓度时的测量范围,减轻了催化剂的高温烧结和挥发现象,延长了载体催化元件的使用寿命。并建立了相应的温度自动控制和甲烷浓度测量的数学模型。     

从WTO规则析我国农业国内支持制度的完善

WTO相关协议允许各国采用一定的农业国内支持措施，尤其是《农产品协定》的绿箱条款更指明了农业国内支持的方向。我国在入世协议中也对农业国内支持作了承诺。为此，要发展农业，应在遵守上述WTO规则的基础上逐步完善我国现行的农业国内支持制度。     

测定小惯性热电偶时间常数新法

研究了用电加热法解决用于动态气流温度测量的小惯性热电偶时间常数的实验测定问题。提出采取在稳定气流场中用电加热热电偶然后迅速切断电源的方法 ,获取较为理想的负温度阶跃 ,进而由热电偶的阶跃响应曲线求得时间常数。设计了相应的设备 ,并进行了实验测定 ,获得了较好的结果。