Swap variance hedging and efficiency: The role of high moments

In this article, we propose a new theoretical approach for developing hedging strategies based on swap variance (SwV). SwV is a generalized risk measure equivalent to a polynomial combination of all moments of a return distribution. Using the S&P 500 index and West Texas Intermediate (WTI) crude oil spot and futures price data, as well as simulations by varying the distribution of asset returns, we investigate the dynamic differences between hedge ratios and portfolio performances based on SwV (with high moments) and variance (without high moments). We find that, on average, the minimizing-SwV hedging suggests more short futures contracts than minimizing-variance hedging; however, when market conditions deteriorate, the minimizing-SwV hedging suggests fewer short positions in futures. The superior posthedge performances of the mean-SwV hedged portfolios over the mean-variance hedged portfolios in highly volatile or extremely calm markets confirm the efficiency of the mean-SwV hedging strategy.     

Asymmetric Volatility and Trading Activity in Index Futures Options

We examine the impact of option trading activity on implied volatility changes to returns in the index futures option market. Controlling for option moneyness, delta‐to‐option‐premium ratio, and liquidity, we find that net buying pressure, profit‐maximization behavior, and liquidity are interrelated and affect asymmetric responses of implied volatilities to returns. Implied volatilities of options with more liquidity, a higher exercise price, and a higher delta‐to‐option‐premium ratio have the most profound asymmetric response.     

Hedging efficiency in the Greek options market before and after the financial crisis of 2008

This study examines the hedging effectiveness of the emerging Greek options market before and after the financial crisis of 2008. We test the hypothesis of market efficiency by analyzing violations of FTSE/ASE-20 index option returns with respect to standard option theory, estimating option risk-premia, and testing the statistical significance of the returns to delta and delta–vega neutral straddles. Our empirical results suggest that, despite a certain level of mispricing, the Athens Derivatives Exchange maintained a relative level of efficiency before 2008. However, the economic crisis has had a significant impact on the Greek options market, as evidenced by more pronounced violations of theoretical predictions observed in option returns and risk-premia. These findings have direct implications for the risk management of international portfolios, since the feasibility and effectiveness of hedging exposure in Greek investments is found to have declined precisely when it is needed the most.     

SIX CHALLENGES IN DESIGNING EQUITY-BASED PAY

The past two decades have seen a dramatic increase in the equitybased pay of U.S. corporate executives, an increase that has been driven almost entirely by the explosion of stock option grants. When properly designed, equity‐based pay can raise corporate productivity and shareholder value by helping companies attract, motivate, and retain talented managers. But there are good reasons to question whether the current forms of U.S. equity pay are optimal. In many cases, substantial stock and option payoffs to top executives–particularly those who cashed out much of their holdings near the top of the market–appear to have come at the expense of their shareholders, generating considerable skepticism about not just executive pay practices, but the overall quality of U.S. corporate governance. At the same time, many companies that have experienced sharp stock price declines are now struggling with the problem of retaining employees holding lots of deep‐underwater options. This article discusses the design of equity‐based pay plans that aim to motivate sustainable, or long‐run, value creation. As a first step, the author recommends the use of longer vesting periods and other requirements on executive stock and option holdings, both to limit managers' ability to “time” the market and to reduce their incentives to take shortsighted actions that increase near‐term earnings at the expense of longer‐term cash flow. Besides requiring “more permanent” holdings, the author also proposes a change in how stock options are issued. In place of popular “fixed value” plans that adjust the number of options awarded each year to reflect changes in the share price (and that effectively reward management for poor performance by granting more options when the price falls, and fewer when it rises), the author recommends the use of “fixed number” plans that avoid this unintended distortion of incentives. As the author also notes, there is considerable confusion about the real economic cost of options relative to stock. Part of the confusion stems, of course, from current GAAP accounting, which allows companies to report the issuance of at‐the‐money options as costless and so creates a bias against stock and other forms of compensation. But, coming on top of the “opportunity cost” of executive stock options to the company's shareholders, there is another, potentially significant cost of options (and, to a lesser extent, stock) that arises from the propensity of executives and employees to place a lower value on company stock and options than well‐diversified outside investors. The author's conclusion is that grants of (slow‐vesting) stock are likely to have at least three significant advantages over employee stock options:

• ? they are more highly valued by executives and employees (per dollar of cost to shareholders);
• ? they continue to provide reasonably strong ownership incentives and retention power, regardless of whether the stock price rises or falls, because they don't go underwater; and
• ? the value of such grants is much more transparent to stockholders, employees, and the press.

     

Accounting‐Based Probabilistic Prediction of ROE,the Residual Income Valuation Model and the Assessment of Mispricing in the Swedish Stock Market

Using Swedish stock market data, this study investigates whether an investment strategy based on publicly available accounting information can generate abnormal investment returns. The strategy involves two steps. First, an accounting‐based probabilistic prediction model of changes in the medium‐term book return on owners' equity (ROE) is estimated. Second, market expectations of changes in medium‐term ROE are assessed through observed stock prices and the residual income valuation model. Stock market positions over 36‐month holding periods are taken when the accounting‐based predictions of ROE and the market expectations differ. Over the period 1983–2003, the investment strategy generated values of Jensen's alpha corresponding to an average monthly excess return for a hedge position of up to 0.8% for a sample of manufacturing companies. In the main this hedge return was caused by strong positive returns to the long positions, and additional analyses show that the returns appear to have been affected by a positive market sentiment bias (i.e., positive ROE surprises being associated with stronger price reactions than negative ROE surprises) making out‐of‐sample inferences somewhat dubious. Furthermore, most of the investment returns accrued over holding periods up to around 1995, with no indications of market mispricing over the last third (1995–2003) of the investment period. The empirical results are consistent with market investors having become more sophisticated in their use of publicly available accounting information over time.     

Robust Measures of Earnings Surprises

Event studies of market efficiency measure earnings surprises using the consensus error (CE), given as actual earnings minus the average professional forecast. If a subset of forecasts can be biased, the ideal but difficult to estimate parameter‐dependent alternative to CE is a nonlinear filter of individual errors that adjusts for bias. We show that CE is a poor parameter‐free approximation of this ideal measure. The fraction of misses on the same side (FOM), which discards the magnitude of misses, offers a far better approximation. FOM performs particularly well against CE in predicting the returns of U.S. stocks, where bias is potentially large.     

Investor sentiment and value and growth stock index options

The paper examines the relationship between both individual and institutional investor sentiment measures and the risk-neutral skewness (RNS) of seven stock index options comprising either growth or value stocks. It provides novel evidence that growth index option prices are affected by sentiment measures. The regression results indicate a significantly positive relationship between sentiment measures and the RNS estimated from four growth index options and a negative relationship with two value index options. The results are economically significant since an associated long–short trading strategy yields high abnormal returns with a Sharpe ratio of up to 1.1 and zero exposure to systematic risk. These high abnormal returns provide evidence of a value premium type anomaly in the index options markets.     

Buy rough,sell smooth

Recent work has documented roughness in the time series of stock market volatility and investigated its implications for option pricing. We study a strategy for trading stocks based on measures of their implied and realized roughness. A strategy that goes long the roughest-volatility stocks and short the smoothest-volatility stocks earns statistically significant excess annual returns of 6% or more, depending on the time period and strategy details. The profitability of the strategy is not explained by standard factors. We compare alternative measures of roughness in volatility and find that the profitability of the strategy is greater when we sort stocks based on implied rather than realized roughness. We interpret the profitability of the strategy as compensation for near-term idiosyncratic event risk.     

The Piotroski F‐score: evidence from Australia

A market‐neutral strategy that is long [short] stocks with a high [low] Piotroski F‐score generates an index‐weighted 0.8 percent pm on S&P/ASX 200 stocks and 1.4 percent pm on smaller stocks. Equal‐weighted returns are higher and in all cases returns are statistically significant. However, the Carhart model alphas are not statistically significant except in the case of equal‐weighted small cap portfolios. For such portfolios, however, most of the alpha comes from the short side and most institutional investors would find them uninvestable due to capacity constraints. A range of tests indicate that analyst neglect does not explain the F‐score premium.     

Stock Volatility during the Recent Financial Crisis

This paper uses monthly returns from 1802 to 2010, daily returns from 1885 to 2010, and intraday returns from 1982 to 2010 in the USA to show how stock volatility has changed over time. It also uses various measures of volatility implied by option prices to infer what the market was expecting to happen in the months following the financial crisis in late 2008. This episode was associated with historically high levels of stock market volatility, particularly among financial sector stocks, but the market did not expect volatility to remain high for long and it did not. This is in sharp contrast to the prolonged periods of high volatility during the Great Depression. Similar analysis of stock volatility in the United Kingdom and Japan reinforces the notion that the volatility seen in the 2008 crisis was relatively short‐lived. While there is a link between stock volatility and real economic activity, such as unemployment rates, it can be misleading.     

Discretely adjusted option hedges

This paper analyses the distribution of returns on a hedged portfolio, consisting of a European call option and its associated stock, when the portfolio is rebalanced at discrete time intervals. Under the assumptions of the Black-Scholes model this distribution is particularly skew. In tests of the average return on a hedged portfolio this skewness leads to biased t-statistics. The paper explores the nature and extent of this bias and suggests procedures for overcoming it. Other aspects of discrete hedging are also discussed.     

Long‐term Performance of Greek IPOs

We analyse the long‐run performance of 254 Greek IPOs that were listed during the period 1994–2002, computing buy‐and‐hold abnormal returns (BHAR) and cumulative abnormal returns (CAR) over 36 months of secondary market performance. The empirical results differ from international evidence and reveal long‐term overperformance that continues for a substantial interval after listing. Measuring these returns in calendar time, we find statistical significance with several of the benchmarks employed. We also find that long‐term overperformance is a feature of the mass of IPOs conducted during a pronounced IPO wave. Cross‐sectional regressions of long‐run performance disclose several significant factors. The study demonstrates that although Greek IPOs overperform the market for a longer period, underperformance eventually emerges, in line with much international evidence. Our interpretation is that the persistence of overperformance over a significant interval is due to excessive supply of issues during the ‘hot IPO period’. Results associated with pricing during the ‘hot IPO period’ indicate positive short‐ (1‐year), medium‐ (2‐year) and negative long‐term (3‐year) performance.     

Rain or Shine: Where is the Weather Effect?

There is considerable empirical evidence that emotion influences decision‐making. In this paper, we use a database of individual investor accounts to examine the weather effects on traders. Our analysis of the trading activity in five major US cities over a six‐year period finds virtually no difference in individuals’ propensity to buy or sell equities on cloudy days as opposed to sunny days. If the association between cloud cover and stock returns documented for New York and other world cities is indeed caused by investor mood swings, our findings suggest that researchers should focus on the attitudes of market‐makers, news providers or other agents physically located in the city hosting the exchange. NYSE spreads widen on cloudy days. When we control for this, the weather effect becomes smaller and insignificant. We interpret this as evidence that the behaviour of market‐makers, rather than individual investors, may be responsible for the relation between returns and weather.     

A High‐Frequency Investigation of the Interaction between Volatility and DAX Returns

One of the most noticeable stylised facts in finance is that stock index returns are negatively correlated with changes in volatility. The economic rationale for the effect is still controversial. The competing explanations have different implications for the origin of the relationship: Are volatility changes induced by index movements, or inversely, does volatility drive index returns? To differentiate between the alternative hypotheses, we analyse the lead‐lag relationship of option implied volatility and index return in Germany based on Granger causality tests and impulse‐response functions. Our dataset consists of all transactions in DAX options and futures over the time period from 1995 to 2005. Analyzing returns over 5‐minute intervals, we find that the relationship is return‐driven in the sense that index returns Granger cause volatility changes. This causal relationship is statistically and economically significant and can be clearly separated from the contemporaneous correlation. The largest part of the implied volatility response occurs immediately, but we also observe a smaller retarded reaction for up to one hour. A volatility feedback effect is not discernible. If it exists, the stock market appears to correctly anticipate its importance for index returns.     

Valuation Effects of Short Sale Constraints: the Case of Corporate Takeovers

We examine the relation between the degree of short sale constraints for acquiring firms' equity and post takeover stock performance. We find that negative long‐run abnormal returns appear to decline (in economic and statistical terms) as the extent and persistence of institutional block‐holder ownership increase, after accounting for the size, book‐to‐market and method of payment effects. In the spirit of Miller (1977) , such evidence implies that the degree of short sale constraints serves as an important determinant of acquiring firms' short‐run overpricing. It appears that the presence of concentrated institutional presence mitigates and in most cases eliminates, through effective arbitrage, any short‐run overpricing that may be responsible for the long‐run underperformance of acquirers, preserving in this way efficiency in the takeover markets.     

Fund Volatility Index using equity market state prices

The Fund Volatility Index (FVX) is proposed as a forward measure of volatility with applications in fund hedging and risk management. The method applies equity market state prices to individual fund pay‐offs. FVX is validated as a predictor of short‐term realised volatility for 30 exchange traded funds. Performance of the method is compared with existing methods using a data set of 14 925 non‐traded funds. FVX has lower bias and higher forecast accuracy than existing methods. As a more general measure, it allows for incorporation of terms to capture individual fund skewness and projection of higher moments of returns.     

Fool's mate: What does CHESS tell us about individual investor trading performance?

We investigate the short‐term relation between individual investor trading and stock returns on the Australian Securities Exchange. Stocks heavily bought by individual investors underperform stocks heavily sold over the subsequent three days, with respective returns on to a long–short portfolio of ?93, ?67 and ?12 basis points on days one, two and three. Individuals underperform in small and mid‐size stocks when they trade passively using limit orders waiting for the market price to move in their favour. Individuals underperform in large stocks when they trade aggressively using marketable orders. Foreign institutions gain from taking the opposite side of individual trades. We present an information asymmetry‐based explanation for the findings.     

Model risk of the implied GARCH-normal model

Model risk causes significant losses in financial derivative pricing and hedging. Investors may undertake relatively risky investments due to insufficient hedging or overpaying implied by flawed models. The GARCH model with normal innovations (GARCH-normal) has been adopted to depict the dynamics of the returns in many applications. The implied GARCH-normal model is the one minimizing the mean square error between the market option values and the GARCH-normal option prices. In this study, we investigate the model risk of the implied GARCH-normal model fitted to conditional leptokurtic returns, an important feature of financial data. The risk-neutral GARCH model with conditional leptokurtic innovations is derived by the extended Girsanov principle. The option prices and hedging positions of the conditional leptokurtic GARCH models are obtained by extending the dynamic semiparametric approach of Huang and Guo [Statist. Sin., 2009, 19, 1037–1054]. In the simulation study we find significant model risk of the implied GARCH-normal model in pricing and hedging barrier and lookback options when the underlying dynamics follow a GARCH-t model.     

The Price of Correlation Risk: Evidence from Equity Options

We study whether exposure to marketwide correlation shocks affects expected option returns, using data on S&P100 index options, options on all components, and stock returns. We find evidence of priced correlation risk based on prices of index and individual variance risk. A trading strategy exploiting priced correlation risk generates a high alpha and is attractive for CRRA investors without frictions. Correlation risk exposure explains the cross-section of index and individual option returns well. The correlation risk premium cannot be exploited with realistic trading frictions, providing a limits-to-arbitrage interpretation of our finding of a high price of correlation risk.