Transaction costs and asset prices: a dynamic equilibrium model

In this article we study the effects of transaction costs onasset prices. We assume an overlapping generations economy witha riskless, liquid bond, and many risky stocks carrying proportionaltransaction costs. We obtain stock prices and turnover in closedform. Surprisingly, a stock's price may increase in transactioncosts, and a more frequently traded stock may be less adverselyaffected by an increase in transaction costs. Calculations basedon the 'marginal' investor overestimate the effects of transactioncosts. For realistic parameter values, transaction costs havevery small effects on stock prices but large effects on turnover.     

Market illiquidity and bounds on European option prices

The paper analyses the impact of illiquidity of a stock paying no dividends on the pricing of European options written on that stock. In particular, it is shown how illiquidity generates price bounds on an option on this stock, even in the absence of other imperfections, such as transaction costs and trading constraints, or the assumption of stochastic volatility. Moreover, price bounds are shown to be asymmetric with respect to the option price under perfect liquidity. This fact explains, under some conditions, the appearance of a smile effect when the implied volatility is estimated from the mid-quote.     

Odd‐lot Costs and Taxation Influences on Stock Dividend Ex‐dates

Abstract:   Past research has revealed significant abnormal ex‐date returns for stock dividends even though the ex‐date is known in advance and the distribution contains no new information. Various researchers have suggested that the higher transaction cost of selling odd‐lot share parcels compared to round‐lot share parcels is a key driver in the abnormal returns. However, no study to date has directly compared the ex‐date price reaction of stock dividends distributed when odd‐lot transaction costs were charged to those issued when odd‐lot costs were not evident. As odd‐lot trade costs were eliminated from the New Zealand Stock Exchange on 1 October, 1991, the New Zealand market provides a unique opportunity to directly test the role, if any, that odd‐lot transactions costs have in explaining stock dividend ex‐date returns. We find that prior to October 1991 stock dividend ex‐dates exhibit significantly positive returns, however, we do not find any significant ex‐date return once the higher odd‐lot transaction costs were removed. The New Zealand market also enables us to examine an imputation tax based argument of the ex‐date price reaction and we find evidence that imputation tax credits have a value greater than zero.     

Corporate Governance, Incentives, and Industry Consolidations

This article studies the determinants of the success of industryconsolidations using a unique sample of firms established atthe time of their initial public offering: roll-up IPOs. Inthese transactions, small, private firms merge into a shellcompany, which goes public at the same time. These firms deliverpoor stock returns; their operating performance mimics thatof comparable firms but does not justify their high initialvaluations. However, if the managers and owners of the firmsincluded in the transaction remain involved in the businessas shareholders and directors, operating and stock price performanceimprove, and future acquisitions are better received by themarket. Higher ownership by the sponsor of the transaction leadsto a reduction in performance, consistent with the view thatthe sponsor's compensation is excessive. These findings highlightthe impact of corporate governance on performance.     

Primes and Scores: An Essay on Market Imperfections

This paper investigates the reported relative mispricing of primes and scores to the underlying stock. Given transaction costs, we establish arbitrage-based bounds on prime and score prices. We then develop a new nonparametric statistical technique to test whether prime and score prices violate these bounds. We find that prime and score prices do exceed stock prices, and often by a considerable amount. We demonstrate that this increased value is most likely due to the score's ability to save on the costs of dynamic hedging. We also show how short sale and trust size constraints impede the ability to arbitrage price disparities.     

Ambiguous Information,Portfolio Inertia,and Excess Volatility

I study the effects of risk and ambiguity (Knightian uncertainty) on optimal portfolios and equilibrium asset prices when investors receive information that is difficult to link to fundamentals. I show that the desire of investors to hedge ambiguity leads to portfolio inertia and excess volatility. Specifically, when news is surprising, investors may not react to price changes even if there are no transaction costs or other market frictions. Moreover, I show that small shocks to cash flow news, asset betas, or market risk premia may lead to drastic changes in the stock price and hence to excess volatility.     

A note on execution costs for stock index futures: Information versus liquidity effects

This paper examines execution costs and the impact of trade size for stock index futures using price-volume transaction data from the London International Financial Futures and Options Exchange. Consistent with Subrahmanyam [Rev. Financ. Stud. 4 (1991) 17] we find that effective half spreads in the stock index futures market are small compared to stock markets, and that trades in stock index futures have only a small permanent price impact. This result is important as it helps to better understand the success of equity index products such as index futures and Exchange Traded Funds. We also find that there is no asymmetry in the post-trade price reaction between purchases and sales for stock index futures across various trade sizes. This result is consistent with the conjecture in Chan and Lakonishok [J. Financ. Econ. 33 (1993) 173] that the asymmetry surrounding block trades in stock markets is due to the high cost of short selling and the general reluctance of traders to short sell on stock markets.     

Optimal hedging in an extended binomial market under transaction costs

We develop an approach to optimal hedging of a contingent claim under proportional transaction costs in a discrete time financial market model which extends the binomial market model with transaction costs. Our model relaxes the binomial assumption on the stock price ratios to the case where the stock price ratio distribution has bounded support. Non-self-financing hedging strategies are studied to construct an optimal hedge for an investor who takes a short position in a European contingent claim settled by delivery. We develop the theoretical basis for our optimal hedging approach, extending results obtained in our previous work. Specifically, we derive a no-arbitrage option price interval and establish properties of the non-self-financing strategies and their residuals. Based on the theoretical foundation, we develop a computational algorithm for optimizing an investor relevant criterion over the set of admissible non-self-financing hedging strategies. We demonstrate the applicability of our approach using both simulated data and real market data.     

Optimal mean-reversion strategy in the presence of bid-ask spread and delays in capital allocations

A portfolio optimization problem for an investor who trades T-bills and a mean-reverting stock in the presence of proportional and convex transaction costs is considered. The proportional transaction cost represents a bid-ask spread, while the convex transaction cost is used to model delays in capital allocations. I utilize the historical bid-ask spread in US stock market and assume that the stock reverts on yearly basis, while an investor follows monthly changes in the stock price. It is found that proportional transaction cost has a relatively weak effect on the expected return and the Sharpe ratio of the investor's portfolio. Meantime, the presence of delays in capital allocations has a dramatic impact on the expected return and the Sharpe ratio of the investor's portfolio. I also find the robust optimal strategy in the presence of model uncertainty and show that the latter increases the effective risk aversion of the investor and makes her view the stock as more risky.     

限制交易政策如何影响期现关系?——对股指期货价格发现功能的实证检验

本文利用2015年中国股市大幅下跌期间,对股指期货严格限制交易政策这一独特事件前后的高频数据,研究限制交易政策对股指期货与股票市场价格引导关系的影响。利用I-S模型和分位数回归方法的实证结果表明:限制交易政策实施前,股指期货对股票市场的价格影响更强,尤其表现在价格急剧下跌时期;限制交易政策显著增加了期货市场交易成本,从而降低了期货市场的信息份额,削弱了其对股票市场的价格影响,并且改变了期货价格对现货价格“助跌强于助涨”的影响模式,增强了股指期货在价格上涨时对股票市场的影响。研究结果一方面直接量化了期货交易成本变动对其价格发现功能的负面影响,另一方面也从价格引导关系的视角提供了股市危机时期股指期货限制交易政策监管效果的实证证据。     

Robust hedging with proportional transaction costs

A duality for robust hedging with proportional transaction costs of path-dependent European options is obtained in a discrete-time financial market with one risky asset. The investor’s portfolio consists of a dynamically traded stock and a static position in vanilla options, which can be exercised at maturity. Trading of both options and stock is subject to proportional transaction costs. The main theorem is a duality between hedging and a Monge–Kantorovich-type optimization problem. In this dual transport problem, the optimization is over all probability measures that satisfy an approximate martingale condition related to consistent price systems, in addition to an approximate marginal constraint.     

Lottery stocks and stop-loss rules

We show that stop-loss rules increase the returns to investment in stocks with lottery features. These stocks typically have sporadic big gains and frequent small losses. However, stop-loss rules can reduce losses and allow investors to receive the gains from large price increases. We also highlight that sell signals of popular technical rules resemble stop-loss rules and are effective at increasing risk-adjusted returns for lottery stock. These rules could have helped investors avoid losses from major historical drawdowns, are particularly beneficial in declining markets, and are robust to the inclusion of transaction costs.     

The fundamental theorem of asset pricing for continuous processes under small transaction costs

A version of the fundamental theorem of asset pricing is proved for continuous asset prices with small proportional transaction costs. Equivalence is established between: (a) the absence of arbitrage with general strategies for arbitrarily small transaction costs ${\varepsilon > 0}${\varepsilon > 0}, (b) the absence of free lunches with bounded risk for arbitrarily small transaction costs ${\varepsilon > 0}${\varepsilon > 0}, and (c) the existence of e{\varepsilon}-consistent price systems—the analogue of martingale measures under transaction costs—for arbitrarily small ${\varepsilon > 0}${\varepsilon > 0}. The proof proceeds through an explicit construction, as opposed to the usual separation arguments. The paper concludes comparing numéraire-free and numéraire-based notions of admissibility, and the corresponding martingale and local martingale properties for consistent price systems.     

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.     

DEBT REFUNDING AND SHAREHOLDER WEALTH: THE PRICE EFFECTS OF DEBT-FOR-DEBT EXCHANGE OFFER ANNOUNCEMENTS

This study examines the impact of debt refunding on common stock prices for a sample of 48 exchange offers announced from 1970 through 1981. Exchange offer announcements do not have a significant impact on average common stock returns but appear to produce idiosyncratic share price effects. Refunding-induced price effects were unrelated to several exchange offer characteristics including tax shield increases, exchange offer premia, and transaction costs of refunding. Common stock excess returns were negatively related to reductions in debt service payments and relaxation of dividend payment constraints. Thus, the evidence is consistent with theories predicting that certain debt refundings generate negative information-signaling price effects.     

Lost in translation: Delayed ex-dividend price adjustments of Hong Kong ADRs

Previous research documents that Hong Kong stocks have a full ex-dividend price adjustment consistent with dividends and capital gains being tax free. We examine ex-dividend price behavior of Hong Kong ADRs to assess the impact of differing tax environments in US and Hong Kong. These ADRs typically go ex-dividend before their underlying stock. They experience significant abnormal returns of 1.16% on their ex-day; the average ex-day price drop is only 30% of the dividend. However, ADR prices drop when the underlying stock goes ex-dividend subsequently. The cumulative ADR price drop is equal to the dividend. Thus, the ADR ex-dividend adjustment resembles that of the underlying stock, consistent with home country tax laws governing ADR price behavior. Neither liquidity nor transaction costs can explain the anomalous delayed ex-dividend adjustment of ADRs.     

REITs,Decimalization, and Ex-dividend Stock Prices

The ex-dividend pricing of real estate investment trust (REIT) stocks under fractional and decimal pricing regimes is investigated. For REITs, with the move from discrete to decimal pricing, the price drop on the ex-dividend day approaches the dividend amount, the ex-date abnormal return decreases, the spread-to-dividend ratio declines, abnormal trading volume increases, and the potential erroneous appearance of a tax-clientele effect is diminished. Discreteness and other transaction costs are reduced with decimalization implying that part of the persistence in the appearance of the tax-clientele effect when modeling ex-dividend stock pricing might be generated by the interaction between transaction costs, dividend amount, and yield.      

To buy or not to buy? The value of contradictory analyst signals

We study the predictive ability of individual analyst target price changes for post-event abnormal stock returns within each recommendation category. Although prior studies generally demonstrate the investment value of target prices, we find that target price changes do not cause abnormal returns within each recommendation level. Instead, contradictory analyst signals (e.g., strong buy reiterations with large target price decreases) neutralize each other, whereas confirmatory signals reinforce each other. Further, our analysis reveals that large target price downgrades can be explained by preceding stock price decreases. However, upgrades are not preceded by stock price increases, thereby demonstrating asymmetric analyst behavior when adjusting target prices to stock prices. Our results suggest that investors should treat recommendations with caution when they are issued with large contradictory target price changes. Thus, instead of blindly following a recommendation, investors might put more weight on the change in the corresponding target price and consider transaction costs.