城市用水量随机梯度回归分析

城市生活用水量的预测在城市水资源利用和节约用水规划管理中起着非常重要的作用。采用随机梯度回归方法建立城市生活用水量预测模型，并利用天津市近年来的用水量数据进行验证，同时与支持向量机方法进行比较，结果表明随机梯度回归的预测精度较高，为城市管理部门在采取切实可行的政策和制定科学的水资源规划方面提供可靠依据。     

女排队员防守起球率与运动素质多元回归分析

在女排运动中,运动员的运动素质指标与防守起球率有着直接的关系。人们通常认为800米跑、立定三级跳远、仰卧起坐、3米折返跑、思维灵敏性、运动知觉和适竞感7项指标与防守起球率有一定的相关性。但它们与防守起球率的回归结果表明:800米跑与防守起球率相关关系不显著;而思维灵敏性、仰卧起坐、3米折返跑、适竞感4项对防守起球率的影响显著,立定三级跳远、运动知觉却相对较弱。     

Are football referees really biased and inconsistent?: evidence on the incidence of disciplinary sanction in the English Premier League

Summary.  The paper presents a statistical analysis of patterns in the incidence of disciplinary sanction (yellow and red cards) that were taken against players in the English Premier League over the period 1996–2003. Several questions concerning sources of inconsistency and bias in refereeing standards are examined. Evidence is found to support a time consistency hypothesis, that the average incidence of disciplinary sanction is predominantly stable over time. However, a refereeing consistency hypothesis, that the incidence of disciplinary sanction does not vary between referees, is rejected. The tendency for away teams to incur more disciplinary points than home teams cannot be attributed to the home advantage effect on match results and appears to be due to a refereeing bias favouring the home team.     

Evaluation of statistical protocols for quality control of ecosystem carbon dioxide fluxes

Summary.  The process of quality control of micrometeorological and carbon dioxide (CO₂) flux data can be subjective and may lack repeatability, which would undermine the results of many studies. Multivariate statistical methods and time series analysis were used together and independently to detect and replace outliers in CO₂ flux data derived from a Bowen ratio energy balance system. The results were compared with those produced by five experts who applied the current and potentially subjective protocol. All protocols were tested on the same set of three 5-day periods, when measurements were conducted in an abandoned agricultural field. The concordance of the protocols was evaluated by using the experts' opinion (mean ± 1.96 standard deviations) as a reference interval (the Bland–Altman method). Analysing the 15 days together, the statistical protocol that combined multivariate distance, multiple linear regression and time series analysis showed a concordance of 93% on a 20-min flux basis and 87% on a daily basis (only 2 days fell outside the reference interval), and the overall flux differed only by 1.7% (3.2 g CO₂ m⁻²). An automated version of this or a similar statistical protocol could be used as a standard way of filling gaps and processing data from Bowen ratio energy balance and other techniques (e.g. eddy covariance). This would enforce objectivity in comparisons of CO₂ flux data that are generated by different research groups and streamline the protocols for quality control.     

Chain ratio and regression type estimators for median estimation in survey sampling

In this paper, we consider chain ratio and regression type estimators for estimating median in survey sampling. We find expressions for the variance of the chain-ratio and chain-regression type estimators considered in the present investigation. The optimum values of the first phase and second phase sample sizes are also obtained for the fixed cost of survey. The relative efficiency of chain-ratio and chain-regression type estimators have been studied in comparison to ratio and regression type estimators of median proposed by Singh, Joarder and Tracy (2001).     

作业基础预算体系研究

综合运用管理会计、管理经济学、数量经济学等有关理论,通过构建需求函数,求出利润最大化下的产品最优销量组合,消除了传统销售预测的人为估计的局限,并结合作业成本法(Activity-BasedCosting,ABC),建立完整、科学的作业基础预算体系。     

论FDI对我国的税收贡献

对外开放、吸引外资是我国的一项长期基本国策,也是各国应对经济全球化、增强本国经济实力所纷纷采取的策略。外商直接投资(FDI)对我国税收增长具有重要的影响。本文以我国1994—2006年的数据为样本,试图运用回归模型分析其对我国税收规模的影响,以此得出我国吸引外资总量与税收总量之间的关系,并提出进一步提高FDI对我国的税收贡献的建议。     

Subject-specific odds ratios in binomial GLMMs with continuous response

In a regression context, the dichotomization of a continuous outcome variable is often motivated by the need to express results in terms of the odds ratio, as a measure of association between the response and one or more risk factors. Starting from the recent work of Moser and Coombs (Stat Med 23:1843–1860, 2004) in this article we explore in a mixed model framework the possibility of obtaining odds ratio estimates from a regression linear model without the need of dichotomizing the response variable. It is shown that the odds ratio estimators derived from a linear mixed model outperform those from a binomial generalized linear mixed model, especially when the data exhibit high levels of heterogeneity.     

Classification and similarity analysis of fundamental frequency patterns in infant spoken language acquisition

Fundamental frequency (F0) patterns, which indicate the vibration frequency of vocal cords, reflect the developmental changes in infant spoken language. In previous studies of developmental psychology, however, F0 patterns were manually classified into subjectively specified categories. Furthermore, since F0 has sequential missing and indicates a mean nonstationarity, classification that employs subsequent partition and conventional discriminant analysis based on stationary and local stationary processes is considered inadequate. Consequently, we propose a classification method based on discriminant analysis of time series data with mean nonstationarity and sequential missing, and a measurement technique for investigating the configuration similarities for classification. Using our proposed procedures, we analyse a longitudinal database of recorded conversations between infants and parents over a five-year period. Various F0 patterns were automatically classified into appropriate pattern groups, and the classification similarities calculated. These similarities gradually decreased with infant’s monthly age until a large change occurred around 20 months. The results suggest that our proposed methods are useful for analysing large-scale data and can contribute to studies of infant spoken language acquisition.     

Goodness-of-fit tests for parametric models in censored regression

The authors propose a goodness-of-fit test for parametric regression models when the response variable is right-censored. Their test compares an estimation of the error distribution based on parametric residuals to another estimation relying on nonparametric residuals. They call on a bootstrap mechanism in order to approximate the critical values of tests based on Kolmogorov-Smirnov and Cramér-von Mises type statistics. They also present the results of Monte Carlo simulations and use data from a study about quasars to illustrate their work.