Short-sale constraints and stock price informativeness

Morck, Yeung, and Yu (2000), in their pioneering study of international differences in stock price synchronicity, emphasize the effect of market development on investors' ability to incorporate firm-specific information into prices. We use a unique institutional feature in the Hong Kong market to investigate one of the important tools investors use to do this and hence reduce stock price synchronicity: short selling. Examining the cross-sectional and time-series variation in short-sale constraints in the Hong Kong market, we find that after the removal of short-sale constraints, stock prices become more informative and move less in tandem with the market.     

Short-sale constraints and informational efficiency to private information: A natural experiment

Exploiting a regulatory change in short-sale constraints (Regulation SHO) as a natural experiment, this paper examines the effect of short-sale constraints on informational efficiency of stock prices to private information. I find that short-sellers act as informed traders prior to forthcoming analyst news and trade on negative private information. When short-sale constraints are relaxed for pilot stocks (treatment group), both trading volume and stock price sensitivity increase prior to the analyst announcement for bad news but not for good news, relative to that of nonpilot stocks (control group). The findings are consistent with the Diamond and Verrecchia model that predicts that short-selling increases the speed of adjustment of stock prices to private negative information. In the cross-section, the effect of Reg SHO is stronger in stocks of firms with weak and uncertain information environments (i.e., small firms and firms with high analyst forecast dispersion).     

Asset pricing with heterogeneous preferences,beliefs, and portfolio constraints

Portfolio constraints are widespread and have significant effects on asset prices. This paper studies the effects of constraints in a dynamic economy populated by investors with different risk aversions and beliefs about the rate of economic growth. The paper provides a comparison of various constraints and conditions under which these constraints help match certain empirical facts about asset prices. Under these conditions, borrowing and short-sale constraints decrease stock return volatilities, whereas limited stock market participation constraints amplify them. Moreover, borrowing constraints generate spikes in interest rates and volatilities and have stronger effects on asset prices than short-sale constraints.     

The value of shorting

This paper assesses the effects of short-sale constraints on asset prices. The analysis focuses on a particular period in Sweden during which shorting stocks was impossible but stock options were traded. Firstly, the effect on both stock options and the underlying stock was investigated jointly by considering deviations from put-call-parity. Secondly, the effects on only the derivatives were investigated by considering their implied volatilites. The main findings are: (i) the impact on pricing are consistent with a short-sale constraint, (ii) these effects are much more pronounced when shorting is not possible, (iii) these effects are not solely attributable to the mispricing of the stock, as previous research indicates, and (iv) access to international shorting markets can alleviate local short-sale constraints.     

Short-sale constraints and stock price crash risk: Causal evidence from a natural experiment

We examine the relation between short-sale constraints and stock price crash risk. To establish causality, we take advantage of a regulatory change from the Securities and Exchange Commission (SEC)’s Regulation SHO pilot program, which temporarily lifted short-sale constraints for randomly designated stocks. Using Regulation SHO as a natural experiment setting in which to apply a difference-in-differences research design, we find that the lifting of short-sale constraints leads to a significant decrease in stock price crash risk. We further investigate the possible underlying mechanisms through which short-sale constraints affect stock price crash risk. We provide evidence suggesting that lifting of short-sale constraints reduces crash risk by constraining managerial bad news hoarding and improving corporate investment efficiency. The results of our study shed new light on the cause of stock price crash risk as well as the roles that short sellers play in monitoring managerial disclosure strategies and real investment decisions.     

How Common Are Intentional GAAP Violations? Estimates from a Dynamic Model

This paper uses data on detected misstatements—earnings restatements—and a dynamic model to estimate the extent of undetected misstatements that violate GAAP. The model features a CEO who can manipulate his firm's stock price by misstating earnings. I find the CEO's expected cost of misleading investors is low. The probability of detection over a five‐year horizon is 13.91%, and the average misstatement, if detected, results in an 8.53% loss in the CEO's retirement wealth. The low expected cost implies a high fraction of CEOs who misstate earnings at least once at 60%, with 2%–22% of CEOs starting to misstate earnings in each year 2003–2010, inflation in stock prices across CEOs who misstate earnings at 2.02%, and inflation in stock prices across all CEOs at 0.77%. Wealthier CEOs manipulate less, and the average misstatement is larger in smaller firms.     

Short-sale refinancing and price adjustment speed to bad news: Evidence from a quasi-natural experiment in China

Short selling may accelerate stock price adjustment to negative news. However, the literature provides mixed evidence for this prediction. Using short-sale refinancing and a staggered difference-in-differences (DID) model, this paper explores the effect of short selling on stock price adjustment. Our results show that (1) short-sale refinancing improves the speed of stock price adjustment to negative news. This result holds after we control for endogeneity. (2) The positive relationship between short-sale refinancing and stock price adjustment speed is significant in subsamples of stocks with higher earnings management or lower accuracy of analyst forecasts, indicating that firms with more opaque information are more likely to be targeted by short sellers. In subsamples of stocks with a higher ownership concentration or lower ownership by institutional investors, short selling is more likely to increase the speed of stock price adjustment, indicating that ownership structure may influence negative news mining. (3) As short-sale refinancing exacerbates the absorption of bad news by stock prices, it increases crash risk. This study enriches the research on the economic consequences of short selling and provides empirical evidence supporting regulations on short selling in China.     

Short-sale constraints and the idiosyncratic volatility puzzle: An event study approach

Using three natural experiments, we test the hypothesis that investor overconfidence produces overpricing of high idiosyncratic volatility stocks in the presence of binding short-sale constraints. We study three events: IPO lockup expirations, option introductions, and the 2008 short-sale ban on financial firms. Consistent with our prediction, we show that when short-sale constraints are relaxed, event stocks with high idiosyncratic volatility tend to experience greater price reductions, as well as larger increases in trading volume and short interest, than those with low idiosyncratic volatility. These results hold when we benchmark event stocks with non-event stocks with comparable idiosyncratic volatility. Overall, our findings suggest that biased investor beliefs and binding short-sale constraints contribute to idiosyncratic volatility overpricing.     

The effect of CEO luck on the informativeness of stock prices: Do lucky CEOs improve stock price informativeness?

CEOs are “lucky” when they are granted stock options on days when the stock price is lowest in the month of the grant, implying opportunistic timing and severe agency problems (Bebchuk et al., 2010). Using idiosyncratic volatility as our measure of stock price informativeness, we find that lucky CEOs improve the informativeness of stock prices significantly. In particular, CEO luck raises the degree of informativeness by 4.39%. Powerful CEOs who can circumvent governance mechanisms and successfully practice opportunistic timing of options grants are so secured in their positions that they have fewer incentives to conceal information, thereby improving informativeness.     

Capital Gains, Dividend Yields, and Expected Inflation

One explanation for the negative relationship between short-horizon stock returns and inflation is that inflation proxies (inversely) for expected future real output. In this paper, I examine the possibility that inflation also proxies for variation in real price/dividend ratios (excess returns). I show that when the covariance between real price/dividend ratios and inflation is nonzero, the relationship between returns and expected inflation differs for the two components of returns: dividend yields and capital gains returns. My empirical evidence demonstrates that dividend yields and capital gains are related differently to expected inflation in U.S. and foreign markets.     

Comparing the information in short sales and put options

Prior work shows that both short sales and put options contain information about future stock prices. In this study, we compare the return predictability in short sales to the return predictability in put options. The motivation for this comparison is based on the theoretical argument that informed traders can choose between short sales and put options when establishing short positions in a particular stocks. Results in this paper suggest that the underperformance of stocks with high short-selling activity is approximately four times larger than the underperformance of stocks with high put-option activity. While stocks that are most likely to face binding short-sale constraints drive the underperformance caused by put-option activity, we still find that short sales are generally more informative about future prices.     

Migrate or not? The effects of regulation SHO on options trading activities

In this study, we investigate the effects of stock short-sale constraints on options trading by exploiting two US Securities and Exchange Commission rule changes under Regulation SHO: Rule 203 (locate and close-out requirements) and Rule 202T (temporary removal of short-sale price tests). We find that stock short selling activities decrease (increase) significantly after Rule 203 (Rule 202T) implementation, supporting the validity of Rule 203 (Rule 202T) as an exogenous increase (decrease) in short-sale constraints. Options volume increases significantly after Rule 203 went into effect and the result is more pronounced among firms with lower levels of institutional ownership and smaller options bid-ask spreads. Therefore, the evidence from Rule 203 suggests that investors may use options as substitutes for stock short sales when short selling is less feasible or more costly due to the locate and delivery requirements. In contrast, we find no significant change in the options trading volume of pilot stocks during the pilot program of Rule 202T. Overall, our results indicate that the impact of short-sale constraints on options trading varies with the types of constraints affected.     

Capital Gains Tax Overhang and Price Pressure

I study whether the capital gains tax is an impediment to selling by some investors and if so, to what degree associated delayed selling affects stock prices. I find that selling decisions by institutions serving tax‐sensitive clients are sensitive to cumulative capital gains, a pattern not observed for institutions with predominantly tax‐exempt clients. Moreover, tax‐related underselling impacts stock prices during large earnings surprises for stocks held primarily by tax‐sensitive investors. The corresponding price reactions are less negative (more positive) with higher cumulative capital gains. This price pressure pattern is more severe when arbitrage is more costly.     

Short selling of ADRs and foreign market short-sale constraints

We examine the effect of home market short-sale constraints on securities that also trade in other countries that have more liberal short-sale rules. In particular, we focus on the case of ADRs traded in the US, as in some cases, the home markets of these ADRs prohibit short selling. We find that short sellers more heavily trade ADRs from countries where short selling is prohibited than from markets where short selling is allowed. Furthermore, we find that the greater levels of short selling in ADRs with binding home-market constraints is driven by stocks with greater dispersion of investors’ opinion, low fundamentals-to-price ratios, and recent price increases. Our results support the hypothesis that short sellers target ADRs with home market short-sale constraints because these ADRs are more often subject to temporary misvaluation.     

Derivatives traders’ reaction to mispricing in the underlying equity

This article examines trading behavior in the options market conditioned on mispricing in the underlying stock. We investigate the price equilibrium between the observed equity asset and the options-implied synthetic share as well as the relative divergence between the two prices. We find a consistently positive relation between the level of stock mispricing and violations of the upper-boundary condition using derivatives, along with an increase in price divergence. To control for the effect of shorting limitations on mispricing, we further examine prices during the short-sale ban in 2008. The results hold and in many instances are more significant during the ban period. Given the persistent disequilibria between the synthetic and observed stock prices, we argue the results are evidence of informed trading in the derivatives market.     

Explanatory factors of the inflation news impact on stock returns by sector: The Spanish case

We study the short run response of daily stock prices on the Spanish market to the announcements of inflation news at an industrial level, deepening the potential explanatory factors of this response (risk-free interest rate, risk premium and growth expectations). We observe a positive and significant response of the stock returns in case of “bad news” (total inflation rate higher than expected one) in recession, and also in case of negative inflation surprises (“good news”) in non-economic recession. This behaviour is consistent with the evolution of the company dividend growth expectations, since we observe that the relationship between this theoretical component of the stock price and the unexpected inflation, to a large extent, seems to explain the observed behaviour.     

我国资产价格波动与通货膨胀关系的理论研究与实证分析

随着次贷危机引发全球性金融危机,学术界对于货币政策是否以及如何对资产价格做出反应的争议再起。本文根据协整分析技术、Granger因果检验方法和误差修正模型,利用1998—2008年中国的季度数据,对资产价格与通货膨胀之间的关系进行了实证研究。实证研究表明：第一,我国资产价格与通货膨胀之间确实存在长期的均衡关系,其中房价变动对通货膨胀的影响大于股价变动对通货膨胀的影响;第二,我国资产价格与通货膨胀之间存在着单向的因果关系,即股票价格与房价上涨是通货膨胀的原因。     

STOCK PRICES AND INFLATION

Numerous empirical studies establish that inflation has a negative short‐run effect on stock returns but few studies report a positive, long‐run Fisher effect for stock returns. Using stock price and goods price data from six industrial countries, we show that long‐run Fisher elasticities of stock prices with respect to goods prices exceed unity and range from 1.04 to 1.65, which tends to support the Fisher effect. We also find that the time path of the response of stock prices to a shock in goods prices exhibits an initial negative response, which turns positive over longer horizons. These results help reconcile previous short‐run and long‐run empirical evidence on stock returns and inflation. Also, they reveal that stock prices have a long memory with respect to inflation shocks, such that investors should expect stocks to be a good inflation hedge over a long holding period. JEL Classification: G12     

Stock returns after major price shocks: The impact of information

This paper focuses on stocks that experience major price changes. Using analyst reports as a proxy, I find that price events accompanied by information are followed by drift, while no-information ones result in reversals. One interpretation of these results is that investors underreact to news about fundamentals and overreact to other shocks that move stock prices. Consistent with this hypothesis, information-based price changes are more strongly correlated with future earnings surprises than no-information ones. Furthermore, drift exists only when the direction of the price move and of the change in analyst recommendations have the same sign. Finally, the ratio of no-information to information-based price shocks is strongly correlated with aggregate implied volatility and also forecasts momentum returns.     

Short-Sale Restrictions and Price Clustering: Evidence from SEC Rule 201

We provide a novel test of information-based theories of price clustering by examining trade, order, and the National Best Bid and Offer (NBBO) quote price clustering during periods when information is removed from the market. We use a natural experiment of short-sale restrictions resulting from Securities and Exchange Commission (SEC) Rule 201 to more effectively determine the impact of information on price clustering. We find evidence of increased price clustering for trades, orders, and NBBO prices during short-sale restrictions. Overall, our findings indicate that short-sale restrictions harm the price discovery process and lead to a reduction in market efficiency.