Rational herd behaviour and informationally efficient security prices have long been considered to be mutually exclusive but for exceptional cases. In this paper we describe the conditions on the underlying information structure that are necessary and sufficient for informational herding and contrarianism. In a standard sequential security trading model, subject to sufficient noise trading, peo...

This paper presents a computer simulated artificial stock market to examine market rationality issues. We construct economic agents with different degrees of irrationality to participate in the stock market. The agents replicate the irrational behaviors described in the psychology and finance literatures and determine the outcome of the market. The main focus of this study is to examine the two...

This paper introduces a new nonparametric test to identify jump arrival times in high frequency financial time series data. The asymptotic distribution of the test is derived. We demonstrate that the test is robust for different specifications of price processes and the presence of the microstructure noise. A Monte Carlo simulation is conducted which shows that the test has good size and power....

Many practitioners point out that the speculative profits of institutional traders are eroded by the difficulty in gauging the price impact of their trades. In this paper, we develop a model of strategic trading where speculators face such a dilemma because of incomplete information about time-varying market liquidity. Unlike the competitive market makers that they trade against, informed trade...

In this paper we simulate the behavior of a population of boundedly rational agents in a two good economy where all agents can spend their time budget for the production of one or both goods or trading. Agents update their strategies according to a simple imitation type learning rule with noise. It is shown that in several different setups both direct trade and trade via mediators who specializ...

We describe conditions on signal distributions that are necessary and sufficient for informational herding in a stylized model of sequential specialist security trading. Curiously, there can be persistent herding even with signals that satisfy the Monotone Likelihood Ratio Property. Price paths are strongly biased in the direction of the herd but prices are also very sensitive to movements agai...

We construct explicitly a bridge process whose distribution, in its own filtration, is the same as the difference of two independent Poisson processes with the same intensity and its time 1 value satisfies a specific constraint. This construction allows us to show the existence of Glosten-Milgrom equilibrium and its associated optimal trading strategy for the insider. In the equilibrium the ins...

Most stock markets are characterized by a number of parallel operating trading systems which interact intensively with each other. Usually, smaller trading platforms take the leading domestic main market as a benchmark in the price discovery process and for closing open trading positions. But what happens if the smaller trading systems suddenly have to act without this benchmark platform? We ex...

This paper documents that speed is crucially important for high-frequency trading strategies based on U.S. macroeconomic news releases. Using order-level data on the highly liquid S&P 500 ETF traded on NASDAQ from January 6, 2009 to December 12, 2011, we find that a delay of 300 ms or more significantly reduces returns of news-based trading strategies. This reduction is greater for high impact ...

Information technology plays a major role to support the process of securities trading. Tactical trading decisions can be implemented more efficiently by gaining access to alternative trading systems, which provide access to additional liquidity and potentially better execution prices. This paper explores the business value provided by to so-called dark pools of liquidity, which can be accessed...