一种适用于非齐次指数增长序列的直接型离散灰色模型

基于灰色模型的背景值表达式及非齐次指数增长序列的形式1,得到了一种一次累加序列与原始序列的关系,给出了系数确定方法,获得了适用于非齐次指数增长序列的直接型离散灰色模型,并给出了系数确定的方法。实例研究表明：本优化模型不仅具有可操作性,而且精度高,效果好。     

中国消费者信心影响因素实证分析

消费者信心是对消费者整体所表现出来的信心程度及其变动的一种测度。使用离散顺序选择模型对2009年第1季度中国大陆消费者信心指数的原始调查数据进行实证分析,结果显示：消费者对未来经济发展的信心受到其对未来就业、收入、生活和投资四个方面信心的显著影响。     

Symbolic computation for approximating distributions of some families of one and two-sample nonparametric test statistics

A conditional saddlepoint approximation was provided by Gatto and Jammalamadaka (1999) for computing the distribution function of many test statistics based on dependent quantities like multinomial frequencies, spacing frequencies, etc. The considerable complexity of the formulas involved can be bypassed by symbolic computation. This article illustrates the effectiveness of symbolic computation to evaluate the saddlepoint approximation for the likelihood ratio, the exponential score, and the Wald-Wolfowitz test statistics. The case of composite hypotheses is also discussed.     

一种有效计算离散Gabor展开的方法(英文)

定义了一种有限和无限序列的实数形式离散Ｇａｂｏｒ展开方式,这种展开方式使用了类似于广泛应用的复数形式Ｇａｂｏｒ展开方式。但前者由于仅涉及实数运算,结果不仅节省大量的运算,而且更便于硬件和软件的实现。另外,实数形式离散Ｇａｂｏｒ展开方式与复数形式离散Ｇａｂｏｒ展开方式有着非常简单的关系,所以前者可以取代后者的运算。     

Nonparametric Identification under Discrete Variation

This paper provides weak conditions under which there is nonparametric interval identification of local features of a structural function that depends on a discrete endogenous variable and is nonseparable in latent variates. The function delivers values of a discrete or continuous outcome and instruments may be discrete valued. Application of the analog principle leads to quantile regression based interval estimators of values and partial differences of structural functions. The results are used to investigate the nonparametric identifying power of the quarter‐of‐birth instruments used in Angrist and Krueger's 1991 study of the returns to schooling.     

Affirmative Action in Higher Education: How Do Admission and Financial Aid Rules Affect Future Earnings?

This paper addresses how changing the admission and financial aid rules at colleges affects future earnings. I estimate a structural model of the following decisions by individuals: where to submit applications, which school to attend, and what field to study. The model also includes decisions by schools as to which students to accept and how much financial aid to offer. Simulating how black educational choices would change were they to face the white admission and aid rules shows that race‐based advantages had little effect on earnings. However, removing race‐based advantages does affect black educational outcomes. In particular, removing advantages in admissions substantially decreases the number of black students at top‐tier schools, while removing advantages in financial aid causes a decrease in the number of blacks who attend college.     

离散型制造企业RFID应用策略研究

本文回顾了RFID在离散制造企业的应用研究成果,分析了应用中存在的主要问题和应用需求.在此基础上,提出了离散制造企业RFID应用的目标和原则,把RFID应用分为单元业务应用、部门级应用、企业整体优化应用和供应链应用四个层次.最后提出了企业的RFID应用策略,并以江淮乘用车关键件跟踪方案为例,验证了策略的合理性.     

Measuring the Implications of Sales and Consumer Inventory Behavior

Temporary price reductions (sales) are common for many goods and naturally result in large increases in the quantity sold. Demand estimation based on temporary price reductions may mismeasure the long‐run responsiveness to prices. In this paper we quantify the extent of the problem and assess its economic implications. We structurally estimate a dynamic model of consumer choice using two years of scanner data on the purchasing behavior of a panel of households. The results suggest that static demand estimates, which neglect dynamics, (i) overestimate own‐price elasticities by 30 percent, (ii) underestimate cross‐price elasticities by up to a factor of 5, and (iii) overestimate the substitution to the no‐purchase or outside option by over 200 percent. This suggests that policy analysis based on static elasticity estimates will underestimate price–cost margins and underpredict the effects of mergers.     

Quantifying Potential Human Health Impacts of Animal Antibiotic Use: Enrofloxacin and Macrolides in Chickens

Use of similar or identical antibiotics in both human and veterinary medicine has come under increasing scrutiny by regulators concerned that bacteria resistant to animal antibiotics will infect people and resist treatment with similar human antibiotics, leading to excess illnesses and deaths. Scientists, regulators, and interest groups in the United States and Europe have urged bans on nontherapeutic and some therapeutic uses of animal antibiotics to protect human health. Many regulators and public health experts have also expressed dissatisfaction with the perceived limitations of quantitative risk assessment and have proposed alternative qualitative and judgmental approaches ranging from "attributable fraction" estimates to risk management recommendations based on the precautionary principle or on expert judgments about the importance of classes of compounds in human medicine. This article presents a more traditional quantitative risk assessment of the likely human health impacts of continuing versus withdrawing use of fluoroquinolones and macrolides in production of broiler chickens in the United States. An analytic framework is developed and applied to available data. It indicates that withdrawing animal antibiotics can cause far more human illness-days than it would prevent: the estimated human BENEFIT:RISK health ratio for human health impacts of continued animal antibiotic use exceeds 1,000:1 in many cases. This conclusion is driven by a hypothesized causal sequence in which withdrawing animal antibiotic use increases illnesses rates in animals, microbial loads in servings from the affected animals, and hence human health risks. This potentially important aspect of human health risk assessment for animal antibiotics has not previously been quantified.