服务企业的报刊媒体评价研究

本文构建了广告投放与消费者电话反应之间的几何滞后分布的动态计量经济模型,并利用实测数据对不同报刊媒体的短期广告效果进行了评价.研究结果显示,所建立的模型可以较好地对同一类广告媒体进行评价和预测;消费者电话反应具有广告的短期刺激-反应特征,以报刊的发行量作为报刊选择的标准可能导致偏差;报刊广告的保留率很低,以报刊广告为主的企业可以考虑每天或隔天作为广告投放的频率.     

C326. Ergodicity for time series and spatial processes

A statistic is presented for testing a three state observed Markov chain for independence. The test procedure is compared with the traditional X ² test. Examples are given in which the proposed test has better power than the X ² test.     

几何曲面VB动态生成方法浅探

探讨了利用VisualBASIC实现几何曲面计算机动态形成的方法。     

The resource constrained multi-item inventory problem with price discount: a geometric programming approach

In this paper we present a geometric programming approach for determining the inventory policy for multiple items having price discount and a limit on the total average inventory of all the items. An example is solved to illustrate the method.     

On Summarizing Group Exposures in Risk Assessment: Is an Arithmetic Mean or a Geometric Mean More Appropriate?

Since substantial bias can result from assigning some type of mean exposure to a group, risk assessments based on epidemiological data should avoid the grouping of data whenever possible. However, ungrouped data are frequently unavailable, and the question arises as to whether an arithmetic or geometric mean is the most appropriate summary measure of exposure. It is argued in this paper that one should use the type of mean for which the total risk that would result if every member of the population was exposed to the mean level is as close as possible to the actual total population risk. Using this criterion an arithmetic mean is always preferred over a geometric mean whenever the dose response is convex. In each of several data sets examined in this paper for which the dose response was not convex, an arithmetic mean was still preferred based on this criterion.     

PROPERLY RESCALED COMPONENTS OF SMOOTH TESTS OF FIT ARE DIAGNOSTIC

The paper illustrates a typical pitfall associated with a conventional interpretation of components of smooth tests of fit, for example the first nonzero components of the smooth tests for Poissonity, exponentiality, normality and the geometric distribution. In order to achieve a directed diagnosis concerning the kind of departure from a hypothesised model, an appropriate rescaling of components is necessary.     

The Maximum of Independent Geometric Random Variables as the Time for Genomic Evolution

□ We calculate the asymptotics of the moments as well as the limiting distribution (after the appropriate normalization) of the maximum of independent, not identically distributed, geometric random variables. In many cases, the limit distribution turns out to be the standard Gumbel. The motivation comes from a variant of the genomic evolutionary model proposed by Wilf and Ewens^{[ 15} Wilf , H.S. , Ewens , W.J . There's plenty of time for evolution . Proc. Nat. Acad. Sci. 2010 , 107 ( 52 ), 22454 – 22456 , doi: 10.1073/pnas.1016207107. [Crossref], [PubMed] , [Google Scholar] ^] as an answer to the criticism of the Darwinian theory of evolution stating that the time required for the appropriate mutations is huge.

A byproduct of our analysis is the asymptotics of the moments as well as the limiting distribution (after the appropriate normalization) of the maximum of independent, not identically distributed, exponential random variables.     

Characterizations of generalized mixtures of geometric and exponential distributions based on upper record values

Let X _{U (1)} < X _{U (2)} < … < X _{U ( n )} < … be the sequence of the upper record values from a population with common distribution function F. In this paper, we first give a theorem to characterize the generalized mixtures of geometric distribution by the relation between E[(X _{U ( n +1)}–X _{U ( n )})²|X _{U ( n )} = x] and the function of the failure rate of the distribution, for any positive integer n. Secondly, we also use the same relation to characterize the generalized mixtures of exponential distribution. The characterizing relations were motivated by the work of Balakrishnan and Balasubramanian (1995). Received: March 31, 1999; revised version: November 22, 1999     

Bayesian estimation of parameters of mixed geometric failure models from Type I group censored sample

The estimation problem of the parameters of a mixed geometric lifetime model, using Bayesian approach and Type I group censored sample, will be investigated in the case of two subpopulations. The Bayes estimates are derived for squared error, minimum expected, general entropy and linex loss functions under informative and diffuse priors. A practical example given by Nelson (W.B. Nelson, Hazard plotting methods for analysis of the life data with different failure models, J. Qual. Technol. 2 (1970), pp. 126–149) is considered. A simulation study is carried out along with risk.     

A new discrete distrlbution,with applications to survival,dispersal and dispersion

We describe a new discrete probability distribution with several useful properties for the analysis and modelling of survival processes and dispersion. First, the model can be used to describe survival processes with monotonically decreasing, constant, or increasing hazard functions, simply by tuning one parameter. Also, the model can describe counts that are overdispersed (contagious) or underdispersed, since the variance can exceed, equal, or be less than the mean. All of these properties are demonstrated both theoretically and with ecological examples, using ad-hoc parameter estimation techniques. Finally, the equations are tractable compared with, say, the negative binomial, and easily incorporated into larger models.