“动态镜头”、“运动镜头”、“运动摄像”及相关概念辨析

在关于电视画面运动的讨论中,有好几个概念都存在彼此牵连、界定不清的问题。为了廓清思路,更好地指导实践,可从拍摄的角度起用一个新概念——“固定拍摄”,以便与传统的“运动摄像”概念形成呼应;从后期剪辑的角度,则可以起用一对新概念——“静态镜头”和“动态镜头”,以适应观众对画面的把握方式;同时,对传统的一对概念“固定镜头”和“运动镜头”相应地需要进行更准确的定位和把握。最后,对与“运动摄像”相关的一系列容易让人误解的传统概念、术语也进行了更为细致的辨别。     

Conditional moving linear regression: Modeling the recruitment process for ALLHAT

Effective recruitment is a prerequisite for successful execution of a clinical trial. ALLHAT, a large hypertension treatment trial (N = 42,418), provided an opportunity to evaluate adaptive modeling of recruitment processes using conditional moving linear regression. Our statistical modeling of recruitment, comparing Brownian and fractional Brownian motion, indicates that fractional Brownian motion combined with moving linear regression is better than classic Brownian motion in terms of higher conditional probability of achieving a global recruitment goal in 4-week ahead projections. Further research is needed to evaluate how recruitment modeling can assist clinical trialists in planning and executing clinical trials.     

Buffon's needle and the estimation of migration distances

A procedure is suggested for estimating migration distances from data on the proportion of migrants crossing regional boundaries. The method makes use of Buffon's needle, a problem in geometrical probability from the eighteenth century that was originally used as an empirical means of estimating π. The procedure is described for various scenarios that differ in their assumptions about region shape, the spatial distribution of population, and the distribution of migration distances. An application to migration distances in the United States is given, and additional attention is given to the estimation of intraregional migration distances.     

Asymptotic behaviour of a test statistic for detection of change in mean of vectors

The paper gives an asymptotic distribution of a test statistic for detecting a change in a mean of random vectors with dependent components. The studied test statistic has a form of a maximum of a square Euclidean norms of vectors with components being standardized partial cumulative sums of deviations from means. The limit distribution was obtained using a result of Piterbarg [1994. High deviations for multidimensional stationary Gaussian processes with independent components. In: Zolotarev, V.M. (Ed.), Stability Problems for Stochastic Models, pp. 197–210].     

空间格义背后的举意与旁观——《日用家当》中“家宅”的心理几何图解

在爱丽丝·沃克的短篇小说《日用家当》中,家宅被赋予了一定的格义属性,这可以被视为19世纪女性主义文学批评语境中的心理现象学介入。家宅格义背后的心理图解划清了个体＂生存空间＂的原型与流变,洋溢着深切的心理几何假设内涵。作者借助不同人物对于家宅的写实性解读,提供了一个富有曲面内涵的边缘记忆空间,揭示了主体的物我元一思想已然深植于家宅意象当中,并以拓扑图腾的同胚形式得以彰显。家宅的心理几何图解立体地刻画了个体在生存空间日渐缩限时的困顿与挣扎,更是直指个体守护本我世界时的一种精神重估,而这正是该部文学作品所隐含的原生代性旨归所在。     

Smooth estimation of a monotone density

We investigate the interplay of smoothness and monotonicity assumptions when estimating a density from a sample of observations. The nonparametric maximum likelihood estimator of a decreasing density on the positive half line attains a rate of convergence of [Formula: See Text] at a fixed point t if the density has a negative derivative at t. The same rate is obtained by a kernel estimator of bandwidth [Formula: See Text], but the limit distributions are different. If the density is both differentiable at t and known to be monotone, then a third estimator is obtained by isotonization of a kernel estimator. We show that this again attains the rate of convergence [Formula: See Text], and compare the limit distributions of the three types of estimators. It is shown that both isotonization and smoothing lead to a more concentrated limit distribution and we study the dependence on the proportionality constant in the bandwidth. We also show that isotonization does not change the limit behaviour of a kernel estimator with a bandwidth larger than [Formula: See Text], in the case that the density is known to have more than one derivative.     

Opportunities of the minimum Anderson–Darling estimator as a variant of the maximum likelihood method

We reveal that the minimum Anderson–Darling (MAD) estimator is a variant of the maximum likelihood method. Furthermore, it is shown that the MAD estimator offers excellent opportunities for parameter estimation if there is no explicit formulation for the distribution model. The computation time for the MAD estimator with approximated cumulative distribution function is much shorter than that of the classical maximum likelihood method with approximated probability density function. Additionally, we research the performance of the MAD estimator for the generalized Pareto distribution and demonstrate a further advantage of the MAD estimator with an issue of seismic hazard analysis.     

A two-sample parametric group sequential procedure for monitoring clinical trials

A group sequential procedure is presented which allows for staggered entry of patients, random loss to followup, and utilizes the flexible boundary approach of Lan and DeMets. The proposed procedure assumes that response times are nearly exponentially distributed. An example as well as simulation studies comparing the performance of the proposed procedure with the group sequential logrank are also presented.     

"三大板块":现代中国文学史的重构

文学的运动形态、理论形态和创作形态应似重构现代中国文学史的“三大板块”;在文学史的结构网络中文学运动形态可视为“史线”、理论形态视为“史魂”,而文学创作形态则是“史体”。