There are two types of stock price manipulation examined in the theoretical literature: insider trading, which involves private information that is true and the public spreading of fraudulent false information. While there is a large empirical literature on insider trading, this is the first empirical article to examine the impact of false, fraudulent public information on stock prices and trading volume. We find that such false information, even after being denied by a credible source such as the SEC, generates both (...) abnormal returns and abnormal trading volume. We also find that the effects of the false information on security returns and volume can be persistent for at least 2 weeks. In addition, we show that perpetrators of false news attacks can make potentially large profits from such market manipulations. (shrink)

In a 2015 article entitled “The Irrelevance of Ethics,” MacIntyre argues that acquiring the moral virtues would undermine someone’s capacity to be a good trader in the financial system and, conversely, that a proper training in the virtues of good trading directly militates against the acquisition of the moral virtues. In this paper, we reconsider MacIntyre’s rather damning indictment of financial trading, arguing that his negative assessment is overstated. The financial system is in fact more internally diverse and dynamic, and (...) more reformable, than suggested by MacIntyre’s treatment. The challenge at the heart of MacIntyre’s claims can be crystallized in the question, “under which conditions, if any, can a person be an effective trader and simultaneously live a worthy human life?” We conclude that there are realistic possibilities of integrity and growth in moral virtue for those who work in the financial sector, at least for those operating in a work environment minimally permissive toward virtue, provided they possess characters of integrity and genuine aptitude for the skills and attitudes required in their professional tasks. (shrink)

This paper examines the role of speculative motives in the determination of commodity prices and specifically food related commodity prices. The motivation for this study is the considerable flow of funds into commodities, the widespread view that the process of financialization has led to greater levels of speculation and that speculation is the primary cause of regular spikes in food prices since the turn of the century. We consider two forms of short-term trading, a biasing influence and a correcting influence, (...) relative to the fundamental price. While both forms of short-term trading are relevant, they are small in terms of their influence on overall prices. We do however find some evidence of an increased role being played by Manipulators during the period most associated with financialization. (shrink)

We develop a framework for assessing security market quality, relating five elements of market design to three metrics of market integrity and two metrics of market efficiency. We empirically implement this integrity–efficiency MQ framework by testing a hypothesis that trade-based ramping manipulation at the close raises execution costs on 24 security markets worldwide. Estimating a simultaneous equations model of ramping incidence, spreads, and the probability of deploying real-time surveillance, we show that quoted bid-ask spreads are positively related to the incidence (...) of MTC across seven liquidity deciles. The magnitude is economically significant; improving market integrity by cutting MTC in half reduces spreads 6–11 %. Allowing direct market access in conjunction with RTS, conducting auctions at the close, and developing regulations that require surveillance, all reduce MTC and thereby lower spreads, assuring better market integrity and enhancing market efficiency. Introducing circuit breakers or prohibiting shorts poses integrity–efficiency tradeoffs. (shrink)