Approximation of density functions by orthogonal series with grouped data

Summary Letg(x) andf(x) be continuous density function on (a, b) and let {ϕ_j} be a complete orthonormal sequence of functions onL ₂(g), which is the set of squared integrable functions weighted byg on (a, b). Suppose that over (a, b). Given a grouped sample of sizen fromf(x), the paper investigates the asymptotic properties of the restricted maximum likelihood estimator of density, obtained by setting all but the firstm of the ϑ_j’s equal to0. Practical suggestions are given for performing estimation via the use of Fourier and Legendre polynomial series. Research partially supported by: CNR grant, n. 93. 00837. CT10.     

A hybrid ARIMA and support vector machines model in stock price forecasting

Traditionally, the autoregressive integrated moving average (ARIMA) model has been one of the most widely used linear models in time series forecasting. However, the ARIMA model cannot easily capture the nonlinear patterns. Support vector machines (SVMs), a novel neural network technique, have been successfully applied in solving nonlinear regression estimation problems. Therefore, this investigation proposes a hybrid methodology that exploits the unique strength of the ARIMA model and the SVMs model in forecasting stock prices problems. Real data sets of stock prices were used to examine the forecasting accuracy of the proposed model. The results of computational tests are very promising.     

网络时代的适时财务监控与公司治理

网络技术应用的普及使传统财务监控的变革已成为公司治理和财务管理的热点话题,本文简要揭示新概念——适时财务监控与公司治理的关系,剖析了公司不同管理层次的适时财务监控的实时需求,从公司治理的基本需要对公司价值流再造、公司信息系统变革和适时财务监控机制重构等三个方面进行了初步研究,为网络适时财务监控在公司治理实务中的应用提供了一个基本框架。     

高校体育社团社会责任对成员组织公民行为的影响——心理契约、组织认同的序列中介作用

为考察高校体育社团社会责任对社团成员组织公民行为的影响,以及心理契约和组织认同在它们之间的多重中介作用,采用问卷法对高校体育社团成员进行调查的结果发现:高校体育社团社会责任能够正向预测组织公民行为,心理契约与组织认同在社会责任与组织公民行为中间起中介作用。高校体育社团社会责任通过4条路径影响组织公民行为:直接作用,心理契约、组织认同的中介作用,心理契约和组织认同的序列中介作用。构建的多重中介模型在一定程度上解释了高校体育社团社会责任对社团成员组织公民行为的影响机制。研究结果表明,高校体育社团重视社会责任有助于提高社团成员心理契约和组织认同,进而提高社团成员组织公民行为。     

习近平新时代中国特色社会主义思想认同机制研究

促进人民群众对习近平新时代中国特色社会主义思想的认同,是当前重大理论和实践问题.而构建动力机制、健全引导机制、完善保障机制有利于强化对习近平新时代中国特色社会主义思想的认同.构建动力机制,需要以实现中华民族伟大复兴的中国梦激发认同的情感动力,以让人民群众有更多获得感、幸福感、安全感增强认同的利益动力,以理论的科学性增加认同的思想动力;健全引导机制,需要以理论研究为支撑,完善教育机制;以正确舆论为导向,强化宣传机制;以阵地建设为平台,健全导向机制;完善保障机制,需要壮大经济基础,突出利益认同;健全民主政治,增强政治认同;坚持文化自信,强化价值认同;夯实民生基础,巩固社会认同;推进绿色发展,提升生态认同.     

基于时间学的思想政治教育时间规律新探

随着即时网络时代的到来，思想政治教育学要实现现代转型，探究者必须紧跟时代行进的步履，发扬探赜索隐、钩深致远的精神，深入揭示和科学应用思想政治教育新规律尤其是时间规律。基于时间学，从社会背景条件、教育对象、教育者、管理者角度去考察，思想政治教育时间规律群大致包括思想政治教育一定要适合时代发展状况规律、思想政治品德形成发展的时间规律、对人们进行思想政治教育的时间规律和思想政治教育时间管理规律等四大类型的一级时间规律。其中，每一类型的一级规律包含诸多二级规律或曰子规律。自觉把握和科学应用这些规律，有助于推动思想政治教育不断从实然状态向应然状态、从必然王国向自由王国飞跃。     

利用伪随机信号系统辨识钻柱系统

用白噪声信号作为输入信号对钻柱系统脉冲响应进行辨识。研究了伪随机信号的特征及伪随机信号产生的方法,得出了用伪随机信号代替白噪声信号辨识钻柱系统脉冲响应的结论。结合输入信号和输出信号,利用钻柱系统的脉冲响应,讨论了钻柱的临界转速、钻柱共振、钻柱与井壁之间的相互作用、所钻地层岩性等钻井工程问题。     

Parameter Estimation of Autoregressive Models Using the Iteratively Robust Filtered Fast-τ Method

Utilizing time series modeling entails estimating the model parameters and dispersion. Classical estimators for autocorrelated observations are sensitive to presence of different types of outliers and lead to bias estimation and misinterpretation. It is important to present robust methods for parameters estimation which are not influenced by contaminations. In this article, an estimation method entitled Iteratively Robust Filtered Fast? τ(IRFFT) is proposed for general autoregressive models. In comparison to other commonly accepted methods, this method is more efficient and has lower sensitivity to contaminations due to having desirable robustness properties. This has been demonstrated by applying MSE, influence function, and breakdown point criteria.     

An Individual Mixed‐Evaluation Method for Career Intervention

Economic issues linked to career counseling are a cause for concern to policy makers in developed countries because they expect career practitioners to provide evidence of the efficiency of career counseling interventions. The aim of this study was to test an individual evaluation method mixing time series (outcomes) and life narrative (processes). The method used 5 items related to 1 client's career decision self‐efficacy and studied the evolution of those items throughout the intervention of 1 career counselor (43 days). Changepoint analysis helped in identifying the changes that have to be taken into account for time series and which are contextualized in the client's verbatim analysis. This mixed method highlighted that the career counselor's intervention increased the client's career decision self‐efficacy. Practitioners could use the methodology proposed in this article to evaluate their interventions. They could also report their practice to clients, employers, and decision makers.     

Trend smoothness achieved by penalized least squares with the smoothing parameter chosen by optimality criteria

This work presents a study about the smoothness attained by the methods more frequently used to choose the smoothing parameter in the context of splines: Cross Validation, Generalized Cross Validation, and corrected Akaike and Bayesian Information Criteria, implemented with Penalized Least Squares. It is concluded that the amount of smoothness strongly depends on the length of the series and on the type of underlying trend, while the presence of seasonality even though statistically significant is less relevant. The intrinsic variability of the series is not statistically significant and its effect is taken into account only through the smoothing parameter.