医院信息系统的安全管理维护

针对医院网络信息系统中易出现的各种安全方面的问题,提出了一系列的解决方法。     

植物单宁的性质及应用

文章综述了植物单宁的性质及其在医药卫生、食品工业、化妆品、革鞣等领域的广泛应用.     

How quickly is temporary market inefficiency removed?

I provide evidence on the length of time it takes for arbitrageurs to exploit attractive investment opportunities. A unique data set from the Internet sports betting market allows me to focus on the speed of investor response in an environment that is not affected by the joint hypothesis problem. The market does not instantly converge to an efficient level after mispricing occurs, but the adjustment process is rapid. Arbitrageurs remove many of these opportunities within minutes of them being created and the majority are gone within an hour. Arbitrage opportunities that are more difficult to find last for longer.     

State-dependent pricing, inflation, and welfare in search economies

We investigate the welfare effects of inflation in economies with search frictions and menu costs. We first analyze an economy where there is no transaction demand for money balances: Money is a mere unit of account. We determine a condition under which strictly positive inflation is desirable. We relate this condition to a standard efficiency condition for search economies. Second, we consider a related economy in which there is a transaction role for money. In the absence of menu costs, the Friedman rule is optimal. In the presence of menu costs, the optimal inflation rate is negative for our numerical examples provided menu costs are small. A deviation from the Friedman rule can be optimal depending on the extent of the search externalities.     

应收账款保理的经济学

一、引言 保理公司是专门负责应收账款管理的金融机构。如果保理商选择购买一个企业的应收账款，它将按应收账款发票面值的一定折扣预先支付给企业一定的资金。@近来有些文献试图检验企业保理决策背后的动机：Mian＆Mian提供了一个综合的实证检验，     

Saddlepoint approximations to the mean and variance of the extended hypergeometric distribution

Conditional inference on 2 x 2 tables with fixed margins and unequal probabilities is based on the extended hypergeometric distribution. If the support of the distribution is large, exact calculation of the conditional mean and variance of the table entry may be computationally demanding. This paper proposes a single‐saddlepoint approximation to the mean and variance. While the approximation achieves acceptable accuracy for ordinary practical purposes, an alternative saddlepoint approximation is provided that gives much closer to exact results. It improves the accuracy of current approximations to up to more than four powers of ten.     

“Panelizing” Repeated Cross Sections

This paper considers the implementation of a non-stationary, heterogeneous Markov model for the analysis of binary dependent variables in a time series of repeated cross-sectional (RCS) surveys. The model offers the opportunity to estimate entry and exit transition probabilities and to examine the effects of time-constant and time-varying covariates on the hazards. We show how maximum likelihood estimates of the parameters can be obtained by Fishers method-of-scoring and how to estimate both fixed and time-varying covariate effects. The model is exemplified with an analysis of the labor force participation decision of Dutch and West German women using ISSP (and other) data from 10 annual Dutch surveys conducted between 1987 and 1996 and 7 annual West German surveys conducted between 1988 and 1994. Some open problems concerning the application of the model are discussed.