Change-point detection for expected shortfall in time series

Expected shortfall (ES) is a popular risk measure and plays an important role in risk and portfolio management. Recently, change-point detection of risk measures has been attracting much attention in finance. Based on the self-normalized CUSUM statistic in Fan, Glynn and Pelger (2018) and the Wild Binary Segmentation (WBS) algorithm in Fryzlewicz (2014), this paper proposes a variant WBS procedure to detect and estimate change points of ES in time series. The strengthened Schwarz information criterion is also introduced to determine the number of change points. Monte Carlo simulation studies are conducted to assess the finite-sample performance of our variant WBS procedure about ES in time series. An empirical application is given to illustrate the usefulness of our procedure.     

Krazy Kimmy's: A Case in Fraud Examination

This two‐part case allows for maximum student engagement through preparation, in‐class discussion, and through a Part B case that is part of the Teaching Note. Through this case, students work to identify possible fraud schemes, plan an investigation, and perform horizontal analysis calculations. Students will learn about the concept of ethical hacking, red flag identification, internal control weaknesses, and investigation considerations for fraud schemes. Further, in‐class planning for next steps and investigation can occur, providing an opportunity for group work and in‐depth learning. This case offers flexibility for instructors in that it can be covered over one class or multiple classes, or can be assigned as an independent or group assignment. This teaching note provides an overview of the case along with guidance for teaching this case.     

Another view on optimal design for estimating the point of extremum in quadratic regression

In this paper we illustrate how certain design problems can be simplified by reparametrization of the response function. This alternative viewpoint provides further insights than the more traditional approaches, like minimax, Bayesian or sequential techniques. It will also improve a practitioner’s understanding of more general situations and their “classical” treatment.     

随机存货决策中的安全库存研究

在有短缺成本下 ,讨论了再定购点的确定 ,着重分析了安全库存的一种简易计算。     

Domestic Support and Border Measures for Processed Horticultural Products

In horticultural markets, trade barriers often apply to the processed products whereas domestic support applies to farm-produced raw commodities. Here we assess the effects of such trade barriers and domestic support by simulating the effects of policy reform on global processing tomato markets, which are faced with modest processed product tariffs and high domestic support in the European Union (EU). Both protection and EU subsidy drive down world welfare, but we find that reducing import tariffs for tomato products would yield greater effects on markets and larger welfare impacts outside Europe than would reductions in EU domestic support.     

Intra-Industry Reactions to Stock Split Announcements

We examine whether favorable information conveyed by stock split announcements transfers to nonsplitting firms within the same industry. On average, nonsplitting firms' shareholders experience positive and significant abnormal returns at the stock split announcements of their industry counterparts. In addition, industrywide and firm-specific characteristics are important determinants in explaining nonsplitting firms' stock returns. These firms' earnings increase significantly, and the earnings changes are positively related to the stock price reactions. Finally, we find no evidence that investors revise the value of nonsplitting firms because they anticipate a decline in earnings volatility.     

Incentives for voluntary disclosure

Rule l0b-5 of the 1934 Securities and Exchange Act allows investors to sue firms for misrepresentation or omission. Since firms are principal–agent contracts between owners – contract designers – and privately informed managers, owners are the ultimate firms’ voluntary disclosure strategists. We analyze voluntary disclosure equilibrium in a game with two types of owners: expected liquidating dividends motivated (VMO) and expected price motivated (PMO). We find that Rule l0b-5: (i) does not deter misrepresentation and may suppress voluntary disclosure or, (ii) induces some firms to adopt a partial disclosure policy of disclosing only bad news or only good news.     

Designs for estimating an extremal point of quadratic regression models in a hyperball

This paper is devoted to studying optimal designs for estimating an extremal point of a multivariate quadratic regression model in the unit hyperball. The problem of estimating an extremal point is reduced to that of estimating certain parameters of a corresponding nonlinear (in parameters) regression model. For this reduced problem truncated locally D-optimal designs are found in an explicit form. The result is a generalization of the results of Fedorov and Müller (1997) for onedimensional quadratic regression function in the unit segment. Received February 2002     

论检验直接成本和间接成本的平衡及平衡点的经济意义

分析了工业企业外购物品检验成本的两个组成部分:检验过程直接投入的要素成本和检验结果失准诱发的问接成本,并分析论证了二者的习性、平衡条件以及平衡点的计算方法及应用。     

VMI模式下最优订货点的仿真研究

通过VMI模式下订货流程的模拟,根据客户订货前置期的历史统计数据或分布函数,利用Arena软件求解配送中心最优订货点。研究表明,仿真分析能获得比常规数学方法更科学合理的最优订货点。