Do Arbitragers Exploit the January Effect?

The January effect has been well documented since the 1970s. This study examines whether the January effect still exists and if it does, whether arbitrageurs exploit it. We find that the January effect is still persistently significant. Furthermore, we find that arbitrageurs appear to exploit the January effect, especially in good market years when the number of losing firms is limited and are therefore more easily identifiable. We also find that the January effect tends to be higher for losing stocks with high arbitrage costs relative to those with low arbitrage costs.     

Online Auction Fraud: Ethical Perspective

Internet fraud is an issue that increasingly concerns regulators, consumers, firms, and business ethics researchers. In this article, we examine one common form of internet fraud, the practice of shill bidding (when a seller in an auction enters a bid on his or her own item). The significant incidence of shill bidding on eBay (in spite of the fact that it is illegal just as it is in live auctions) exemplifies the current ineffectiveness of regulatory means as well as the lack of effective societal mechanisms to prevent online fraud. Further, the proliferation of shill bidding along with other types of internet fraud may have broader implications. If unethical behavior such as shill bidding becomes too widespread on the internet, regulators and other societal forces may deem it necessary to institute controls that will impact the entire online marketplace as well as the future development and regulation of business activities on the internet. Our results indicate that shill bidding is perpetrated on eBay significantly more often than 0.1% rate of fraud estimated by the firm. This suggests that regulators, users, and others stakeholders may become concerned enough to act. The impact of those responses on the internet of the future may affect a broad array of users beyond the unethical sellers on eBay. Alex Nikitkov is an Assistant Professor of Accounting at Brock University in St. Catharines, Ontario, Canada Darlene Bay is an Assistant Professor of Accounting at Brock University in St. Catharines, Ontario, Canada     

Consumer motivations and concerns in online auctions: an exploratory study

This investigates the reasons behind the dramatic growth of Internet auction companies such as eBay, exploring into why so many consumers have been motivated to turn to online auctions to purchase and sell goods. It is found that the ability to purchase items at lower prices than from retail stores is the primary motivation, along with having access to previously unobtainable items. Concerns mainly relate to potential fraudulent transactions, although the negative feedback system is found to be vital in the reduction of fears over fraud. Interaction with other auction users is found to be important for practical reasons such as information seeking, rather than for enjoyment. The main conclusion is that the benefits of using Internet auctions far outweigh the risks involved.     

The Inefficiency of First and Second Price Auctions in Dynamic Stochastic Environments

First and second price auctions are optimal mechanisms for resource allocation in many situations and are used widely. However, unlike the static once-and-for-all situations for which auctions are efficient, in dynamic stochastic environments these standard auctions cannot necessarily support optimal allocations. The potential inefficiency of auctions is demonstrated by example. A computer server is modeled as a non-interruptible M/M/1 system, with heterogeneous users. The optimal allocation of jobs is derived, and it is shown that this allocation cannot be supported as either a first-price or a second-price auction equilibrium.     

How Seller and Product Characteristics Impact Promotion on eBay

This study draws on signaling theory to test whether seller and product characteristics impact the use of display-type versus informational-type promotion on eBay. The authors predict that display-type promotion is used by less-experienced sellers who cannot promote on the basis of their own seller ratings. The authors predict that experienced sellers, on the other hand, prefer informational promotion since their high ratings make seller-provided statements more credible. In addition to seller characteristics, the authors predict that product characteristics, such as price and product condition, also impact promotion. It is expected that higher prices drive greater investments in display-type promotions overall, even if such promotion is less effective. Finally, it is hypothesized that the better the condition of the product, the greater the use of informational promotion since this kind of disclosure is especially influential. The hypotheses were tested using a large data set of auction data from eBay and received excellent support. Implications and directions for future research are discussed.     

eBay as the “Terminator”: Determining User Suspension From Feedback Ratings

Good reputations are won and lost by individuals and companies in various forms on the Internet. eBay has the earliest and most well-known formal ecommerce reputation system and “terminates” members who do not play by the rules. We examine a dataset of 102,035 Not-A-Registered-User (NARU) eBay account feedback ratings from eight different countries. Careful investigation of feedback density over time reveals that threshold values for termination can be detected from feedback history. Several modeling approaches are studied and the Local Polynomial Regression Model (LPRM) is chosen for analysis because it is data driven and no prespecified parametric functional form is assumed. Analyzing US data, we find that large-volume sellers have a higher overall negative feedback compared to those of medium volume sellers. We use the second derivative of the LPRM to explicitly determine the threshold points, that is, the point where a seller's negative feedback increases significantly. These thresholds vary from as much as 18.5 weeks prior to termination (for Medium sellers), to as little as 8.5 weeks (for Large sellers). We find similar results in the other countries. These threshold points provide valuable information for buyers when choosing a seller. Our analysis suggests that eBay's termination policy appears to be correlated to fee revenue.     

基于因子分析的套利定价模型及实证研究

众所周知,建立套利定价模型的关键在于因素的筛选,计算量很大。而因子分析能将为数众多的原始指标变量经过分析综合为少数几个公共因子变量,从而大大减少计算的复杂度。本文利用因子分析的方法对11个因素进行筛选,确定四个能够很好地反映所有因素包含的信息但又互不相关的公共因子变量,并建立套利定价模型,实证检验说明,通过该方法进行因素筛选建立的套利定价模型具有较好的定价效果。     

中国概念股指期货跨市场套利研究——基于沪深300指数、H股指数、新华富时A50指数期货的实证分析

针对沪深300指数、H股指数、新华富时A50指数期货,给出确定投资比例、选择投资时机及度量投资风险的方法,对中国概念股指期货的跨市场套利机会进行研究,结论显示:中国沪深300股票指数与周边市场的中国概念股票指数之间存在着普遍关联性,并且这种关联性可以转化为套利机会.实证结果表明:当1∶0.836546作为A50股指期货与H股股指期货的持仓比时,可以得到最优套利结果.     

OPTION PRICING USING THE TERM STRUCTURE OF INTEREST RATES TO HEDGE SYSTEMATIC DISCONTINUITIES IN ASSET RETURNS1

This paper demonstrates the use of term-structure-related securities in the design of dynamic portfolio management strategies that hedge certain systematic jump risks in asset return. Option pricing formulas based on the absence of arbitrage opportunities in this context are also developed. the analysis is for the case where assets returns are driven by a finite number of Brownian motions and an m-variate point process. the inclusion of :the additional traded assets in the term structure makes it possible to hedge systematic jumps imbedded in the m variate point process.     

The Hierarchy of Internet Communication Effects: A New Paradigm for Understanding Internet Promotion

ABSTRACT

The applicability of the traditional marketing models to online marketplaces has been of great interest since the advent of the Internet. This study examines the applicability of the Hierarchy of Communication Effects model to the online auction environment through the use of proprietary archival data. The results provide support for a new model, which we call the Hierarchy of Internet Communications Effects, which is applicable to online environments. The Hierarchy of Internet Communications Effects is analogous to other hierarchical effects models from consumer behavior literature known as the learning hierarchies. We provide suggestions to promote products or services at different stages in the Hierarchy of Internet Communications Effects; several implications and limitations are discussed, and future research is suggested.     

指数期货套利交易策略设计

在期货市场上 ,指数期货是一种股票的避险工具。由于时间及其它因素 ,使得指数期货市场发生不平衡的现象 ,此一不平衡我们称之为套利空间。如何运用金融工程和信息技术来计算出其套利空间 ,为投资人赢得更多的利润 ,正是本研究的宗旨。本文针对指数期货的特性来寻找实时套利机会 ,明确地指出了买低卖高的方向及套利空间的大小 ,并给投资者设计了指数期货套利的交易策略。     

Effect of Buyer and Seller Experience on Buy It Now Pricing

ABSTRACT

Although auctions have been around for centuries, online auctions are still a relatively new phenomenon. This paper examines the phenomenon of online auctions, specifically on a pricing option known as “Buy It Now.” With this option, a buyer can purchase merchandise immediately at a stated price and truncate the auction process. Auction items sold with a Buy It Now price tend to be at a higher price than the high bid price for an identical item sold through an ascending-bid auction. In addition, Buy It Now prices tend to attract risk averse bidders while high bidders of ascending-bid auctions tend to be less risk averse or risk neutral bidders. On the other hand, we found more experienced sellers sell their items with a Buy It Now price while less experienced sellers sell their items through an ascending-bid process. Thus, experience and risk are factors in choosing a Buy It Now price for the seller and buyer.     

NO‐ARMAGEDDON MEASURE FOR ARBITRAGE‐FREE PRICING OF INDEX OPTIONS IN A CREDIT CRISIS

In this work, we consider three problems of the standard market approach to credit index options pricing: the definition of the index spread is not valid in general, the considered payoff leads to a pricing which is not always defined, and the candidate numeraire for defining a pricing measure is not strictly positive, which leads to a nonequivalent pricing measure. We give a solution to the three problems, based on modeling the flow of information through a suitable subfiltration. With this we consistently take into account the possibility of default of all names in the portfolio, that is neglected in the standard market approach. We show on market inputs that, while the pricing difference can be negligible in normal market conditions, it can become highly relevant in stressed market conditions, like the situation caused by the credit crunch.     

APPROXIMATE COMPLETENESS WITH MULTIPLE MARTINGALE MEASURES

We construct a financial market with countably many securities for which there are two equivalent martingale measures under which the market is approximately complete. Thus, approximate completeness does not in general guarantee unique consistent prices for nonmarketed claims. the construction also produces an economy with two agents and infinitely many traded goods which is in equilibrium but has no equilibrium when a new good (recognized by all as redundant) is tentatively traded.