Insider trading and risk aversion

This paper is a continuous time version of Holden and Subrahmanyam (Economics Letters 44 (1994) 181). The paper extends Kyle (Econometrica 53 (1985) 1315) by introducing risk aversion on the side of the monopolist informed trader and allows for the liquidity traders instantaneous demand to depend on cost of trading, as well as on the risk of the stock. The main result of the paper is that, in equilibrium, the price pressure decreases with time regardless of the elasticity of the liquidity demand function.     

Stock splits to profit insider trading: Lessons from an emerging market

Stock splits have long presented financial puzzles: Why are they undertaken? Why are they associated with abnormal returns? Abnormal returns, particularly those coming shortly before a split’s announcement date, should raise strong suspicions of insider trading, particularly in nations with weak regulatory structures. We examined the 718 split events in the emerging stock market of Vietnam from 2007 through 2011. We found evidence consistent with illegal insider trading, particularly in firms that were vulnerable to insider manipulation and, therefore, more likely to split their stocks. When vulnerable firms’ stocks did split, they provided significant excess short-term returns. Tellingly, the abnormal returns on those stocks prior to the split announcements were also extremely high, indeed higher than their abnormal post-announcement returns. Moreover, trading volume increased prior to the split announcement date. This suspicious pattern is what we would expect if insiders were trading on their knowledge. We propose that illegal insider trading in contexts where it is possible to escape serious penalty provides a previously undiscussed and cogent explanation for both stock splits and abnormal short-term returns.     

The price discovery role of day traders in futures market: Evidence from different types of day traders

Using proprietary account-level transaction data in the futures market where day traders are self-declared ex ante, this study investigates whether day traders enhance price discovery at the market level. From a natural classification of day traders, we find that heterogeneous day traders have differential effects on price discovery. Self-declared day traders, who benefit from low margin requirement, do not improve price discovery measured by information share. In contrast, non-declared traders, who are not self-declared as day traders, improve price discovery. Their positive impacts on price discovery are particularly significant during periods of high volatility and arrival of new information. Overall, a margin stimulating policy may encourage more day trading, but may also attract overconfident investors, especially inexperienced ones, and who do not enhance price discovery.     

The price of liquidity: CD rates charged by money market funds

We examine the cost of liquidity in rates on CDs purchased by money market funds (MMFs). We find no evidence that rates vary directly with the size of CDs. However, we do find that large MMFs receive higher rates on large CDs than small MMFs. This suggests banks pay for (potential) liquidity.     

Strategic trading and learning about liquidity

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 traders do not know the distribution of liquidity (“noise”) trades. Instead, they have to learn about liquidity from past prices and trading volume. This learning implies that strategic trades and market statistics such as informational efficiency are path-dependent on past market outcomes. Our paper also has normative implications for practitioners.     

Pricing of time-varying liquidity risk in Finnish stock market: new evidence

Using two recently developed illiquidity measures, we estimate a conditional version of liquidity-adjusted capital asset pricing model (LCAPM), which allows for a time-varying decomposition of the total illiquidity premium into a level component and three risk components. The total estimated annualized illiquidity premium for the Finnish equities during 1997–2015 is 1.13–1.90% depending on the illiquidity measure. Of the three systematic liquidity risk components, risk arising from hedging of wealth shocks is the most important followed by commonality in liquidity risk, whereas flight to liquidity risk is not significantly priced in the Finnish stock market. Our results show that the liquidity risk is time varying, therefore the models estimating the risk-return relationship should address the issue of conditionality.     

Insider trading with correlation between liquidity trading and a public signal

We analyse a Kyle-type continuous-time market model in which liquidity trading is correlated with a noisy public signal that is released continuously. We show that, in contrast to the previous literature, Kyle's λ, the price sensitivity to the order flow, can even be non-monotonic, depending on the correlation structure. We also show that the introduction of an additional public signal does not necessarily improve the informational efficiency of the market, depending on the correlation.     

Endogenous liquidity in credit derivatives

We study the determination of liquidity provision in the single-name credit default swap (CDS) market as measured by the number of distinct dealers providing quotes. We find that liquidity is concentrated among large obligors and those near the investment-grade/speculative-grade cutoff. Consistent with endogenous liquidity provision by informed financial institutions, more liquidity is associated with obligors for which there is a greater information flow from the CDS market to the stock market ahead of major credit events. Furthermore, the level of information heterogeneity plays an important role in how liquidity provision responds to transaction demand and how liquidity is priced into the CDS premium.     

Order-to-trade ratios and market liquidity

We study the impact on market liquidity of the introduction of a penalty for high order-to-trade ratios (OTRs), implemented by the Italian Stock Exchange to curtail high-frequency quote submission. We find that the fee is associated with a collapse in the quoted depth of the stocks that make up the bulk of trading in Italian equities and with an increase in price impacts of trading across the treated stocks. Spreads do not change, however. Stocks from a pan-European control sample show no such liquidity changes. Thus, the Italian OTR fee had the effect of making Italian stocks markets more shallow and less resilient. Large stocks are more severely affected than midcaps. We also find evidence of a limited decrease in turnover. Consolidated liquidity, constructed by aggregating across all electronic trading venues for these stocks, decreases just like that on the main exchange. Thus, liquidity was not simply diverted from the main exchange, it was reduced in aggregate.     

A market model with medium/long-term effects due to an insider

In this article, we consider a modification of the Karatzas–Pikovsky model of insider trading. Specifically, we suppose that the insider agent influences the long/medium-term evolution of Black–Scholes type model through the drift of the stochastic differential equation. We say that the insider agent is using a portfolio leading to a partial equilibrium if the following three properties are satisfied: (a) the portfolio used by the insider leads to a stock price which is a semimartingale under his/her own filtration and his/her own filtration enlarged with the final price; (b) the portfolio used by the insider is optimal in the sense that it maximises the logarithmic utility for the insider when his/her filtration is fixed; and (c) the optimal logarithmic utility in (b) is finite. We give sufficient conditions for the existence of a partial equilibrium and show in some explicit models how to apply these general results.     

Term premium dynamics in an emerging market: Risk,liquidity, and behavioral factors

This paper contributes to the fixed income research by identifying determinants of term premium in an emerging market’s treasury bond yields with particular attention on ambiguity. We use Nelson–Siegel yield curves generated from daily bond price quotes as input to construct a three-factor affine term structure model which decomposes observed yields into risk-neutral and term premium components. We also construct an ambiguity index using intraday FX return data following Brenner and Izhakian (2018). Our analyses suggest that a combination of factors representing market risk, credit risk, liquidity, ambiguity, and investor sentiments can explain majority of the variation in term premia. Explanatory power of credit risk measures are found to increase while those of volatility, ambiguity, and sentiment measures diminish with the maturity horizon. The results imply that ambiguity aversion of bond investors is a major determinant of the shape of the yield curve as it drives the premia for short end of the yield curve lower in line with the expectation of flight-to-safety behavior.     

Two months in the life of several gilt-edged market makers on the London Stock Exchange

We investigate the micro structure of the UK gilt market studying the behaviour of several gilt-edged market makers on the London Stock Exchange. Through a structural model of the price process we can test different microstructural hypotheses, concerning information asymmetries, transaction and inventory carrying costs, and market liquidity. Our results suggest that inventories do not alter the price process in the gilt market. Moreover, in contrast to customer orders, inter-dealer transactions possess an information content. Transaction costs in the inter-dealer market are also substantially smaller than those for external customers.     

Overconfidence among option traders

The investor overconfidence theory predicts a direct relationship between market‐wide turnover and lagged market return. However, previous research has examined this prediction in the equity market, we focus on trading in the options market. Controlling for stock market cross‐sectional volatility, stock idiosyncratic risk, and option market volatility, we find that option trading turnover is positively related to past stock market return. In addition, call option turnover and call to put ratio are also positively associated with the past stock market return. These findings are consistent with the overconfidence theory. We also find that overconfident investors trade more in the options market than in the equity market. We rule out explanations other than investor overconfidence, such as momentum trading and varying risk preferences, for our findings.     

Dynamic portfolio optimization with liquidity cost and market impact: a simulation-and-regression approach

We present a simulation-and-regression method for solving dynamic portfolio optimization problems in the presence of general transaction costs, liquidity costs and market impact. This method extends the classical least squares Monte Carlo algorithm to incorporate switching costs, corresponding to transaction costs and transient liquidity costs, as well as multiple endogenous state variables, namely the portfolio value and the asset prices subject to permanent market impact. To handle endogenous state variables, we adapt a control randomization approach to portfolio optimization problems and further improve the numerical accuracy of this technique for the case of discrete controls. We validate our modified numerical method by solving a realistic cash-and-stock portfolio with a power-law liquidity model. We identify the certainty equivalent losses associated with ignoring liquidity effects, and illustrate how our dynamic optimization method protects the investor's capital under illiquid market conditions. Lastly, we analyze, under different liquidity conditions, the sensitivities of certainty equivalent returns and optimal allocations with respect to trading volume, stock price volatility, initial investment amount, risk aversion level and investment horizon.     

Stock market liquidity and firm value

This paper investigates the relation between stock liquidity and firm performance. The study shows that firms with liquid stocks have better performance as measured by the firm market-to-book ratio. This result is robust to the inclusion of industry or firm fixed effects, a control for idiosyncratic risk, a control for endogenous liquidity using two-stage least squares, and the use of alternative measures of liquidity. To identify the causal effect of liquidity on firm performance, we study an exogenous shock to liquidity—the decimalization of stock trading—and show that the increase in liquidity around decimalization improves firm performance. The causes of liquidity's beneficial effect are investigated: Liquidity increases the information content of market prices and of performance-sensitive managerial compensation. Finally, momentum trading, analyst coverage, investor overreaction, and the effect of liquidity on discount rates or expected returns do not appear to drive the results.     

Measuring liquidity commonality in financial markets

This paper contributes to the literature by developing a new methodology, termed the beta index, for measuring liquidity commonality in financial markets which is derived from the dynamics of liquidity co-movements. We show that computing the beta index is a straightforward process. In addition, not only is the proposed beta index more efficient in controlling for confounding factors and addressing the associated statistical inference issues, but it will also enhance the accuracy of estimation. We apply the beta index to track liquidity commonality in the foreign exchange markets over the study period and to identify important financial and economic events that caused liquidity commonality. We detect periods of high and low liquidity commonalities that would especially benefit active market traders who frequently rebalance portfolios and require knowledge of liquidity commonality as an important early signal and indication of diversification benefit.     

The implied liquidity premium for equities

Over the long term, the returns on smaller stocks are likely to be higher than the returns on larger stocks. This phenomenon has been called size effect, and a number of explanations have been proposed to account for it. Here we show that the difference in return between the larger and the smaller stocks can be accounted for by a liquidity premium for the smaller stocks, and we estimate the value of this premium using structural parameters for the capital distribution of the U.S. stock market during the 1990s The authors wish to express their gratitude to an anonymous referee for a very thorough and incisive reading, as well as for many constructive suggestions that have significantly improved this paper. The authors wish to express their gratitude to an anonymous referee for a very thorough and incisive reading, as well as for many constructive suggestions that have significantly improved this paper.     

Patterns in cross market liquidity

Academic research on liquidity has generally focused on explaining what can be called within market liquidity. That is it seeks to explain things like why one stock is more liquid than another. But there has been considerably less attention to cross market liquidity: the issue of why some securities are more liquid than others. For example, stocks are apparently far more liquid than high yield bonds. Why? Why do some markets exist (orange juice for example) while others do not (potatoes for example)? This article lays out the current academic evidence regarding liquidity across assets and explains why current theories have trouble with one item or another. The challenge then is to produce an overarching theory that offers predictions that are closer to what the data seems to imply about cross market liquidity.     

对我国股市流动性问题的几点思考

本文提出换手率指标不能用来衡量股市流动性,并按国际市场和学术界对流动性的界定对我国股市流动性进行了分析,得出我国股市流动性在国际上处于较低水平;并分析了造成这种状况的原因主要有市场结构、交易机制和监管环境等方面;最后提出了改善我国股市流动性的一些对策。     

Latency and liquidity provision in a limit order book

We use a recent, high-quality data set from Nasdaq to perform an empirical analysis of order flow in a limit order book before and after the arrival of a market order. For each of the stocks that we study, we identify a sequence of distinct phases across which the net flow of orders differs considerably. We note that some of our results are consistent with the widely reported phenomenon of stimulated refill, but that others are not. We therefore propose alternative mechanical and strategic motivations for the behaviour that we observe. Based on our findings, we argue that strategic liquidity providers consider both adverse selection and expected waiting costs when deciding how to act.