Separating a mixture of two normals with proportional covariances

We propose a simple affine equivariant clustering method, based on the idea of best linear classification, for samples from a mixture of two multivariate normal distributions with different mean vectors but proportional covariance matrices. To ameliorate the curse of dimensionality, a non-parametric approach to find candidates for a best linear discriminant function is presented. By using simulation studies and a real example, we show that for large samples in high dimensions, the proposed method can be a useful supplement to general-purpose multivariate outlier detection methods.     

Stock returns following large 1-month declines and jumps: Evidence of overoptimism in the German market

We analyze the short-run and long-run performance of the largest 100 German firms that experience monthly stock price changes of more than ±20% between 1990 and 2003. The results indicate that the return patterns following large price increases are consistent with the overreaction hypothesis, but those following price declines indicate underreaction. Thus, our results support an overoptimism hypothesis for the German market. Further, for price decreases we find strong evidence of a size effect, while for price increases, market-to-book-ratios seem to play a role in determining the magnitude of the reaction. No evidence is found supporting the uncertain information hypothesis.     

Risk,jumps, and diversification

We test for price discontinuities, or jumps, in a panel of high-frequency intraday stock returns and an equiweighted index constructed from the same stocks. Using a new test for common jumps that explicitly utilizes the cross-covariance structure in the returns to identify non-diversifiable jumps, we find strong evidence for many modest-sized, yet highly significant, cojumps that simply pass through standard jump detection statistics when applied on a stock-by-stock basis. Our results are further corroborated by a striking within-day pattern in the significant cojumps, with a sharp peak at the time of regularly scheduled macroeconomic news announcements.     

Overnight stock returns,intraday returns,and firm-specific investor sentiment

In this study, we propose a new index for measuring firm-specific investor sentiment using overnight and intraday stock returns. We use actual equity data to construct the firm-level investor sentiment index and find that the new index has characteristics expected of a sentiment measure. In addition, we propose a novel sentiment-weighted trading strategy and apply it to momentum and short-term reversal strategies. We find that the sentiment-weighted trading strategy generates better performance in momentum and short-term reversal strategies. The sentiment-weighted trading strategy’s superior performance is evidence that our firm-level investor sentiment index possesses predictive powers with regard to future returns.     

Jumps in cross‐sectional rank and expected returns: a mixture model

We propose a new nonlinear time series model of expected returns based on the dynamics of the cross‐sectional rank of realized returns. We model the joint dynamics of a sharp jump in the cross‐sectional rank and the asset return by analyzing (1) the marginal probability distribution of a jump in the cross‐sectional rank within the context of a duration model, and (2) the probability distribution of the asset return conditional on a jump, for which we specify different dynamics depending upon whether or not a jump has taken place. As a result, the expected returns are generated by a mixture of normal distributions weighted by the probability of jumping. The model is estimated for the weekly returns of the constituents of the SP500 index from 1990 to 2000, and its performance is assessed in an out‐of‐sample exercise from 2001 to 2005. Based on the one‐step‐ahead forecast of the mixture model we propose a trading rule, which is evaluated according to several forecast evaluation criteria and compared to 18 alternative trading rules. We find that the proposed trading strategy is the dominant rule by providing superior risk‐adjusted mean trading returns and accurate value‐at‐risk forecasts. Copyright © 2008 John Wiley & Sons, Ltd.     

Jump tails,extreme dependencies,and the distribution of stock returns

We provide a new framework for estimating the systematic and idiosyncratic jump tail risks in financial asset prices. Our estimates are based on in-fill asymptotics for directly identifying the jumps, together with Extreme Value Theory (EVT) approximations and methods-of-moments for assessing the tail decay parameters and tail dependencies. On implementing the procedures with a panel of intraday prices for a large cross-section of individual stocks and the S&P 500 market portfolio, we find that the distributions of the systematic and idiosyncratic jumps are both generally heavy-tailed and close to symmetric, and show how the jump tail dependencies deduced from the high-frequency data together with the day-to-day variation in the diffusive volatility account for the “extreme” joint dependencies observed at the daily level.     

Spillovers of currency carry trade returns,market risk sentiment,and U.S. market returns

This paper examines the link between spillovers of currency carry trade returns and U.S. market returns. Following Tse and Zhao (2012), this paper hypothesizes that the magnitude of spillovers of currency carry trade returns is positively correlated with market risk sentiment and, therefore, has an impact on market returns. Using the G10 currencies and S&P 500 index futures, the empirical results present a high magnitude of spillover effects of currency carry trade markets. The empirical findings also show a significantly positive relationship between spillovers of currency carry trade returns and subsequent market returns. Furthermore, the results indicate that this relationship is stronger in bear markets than in bull markets. Finally, our findings show that spillovers of currency carry trade returns significantly affect the subsequent transition probabilities of market returns.     

Liquidity,earnings management,and stock expected returns

This paper examines the relationships among liquidity, earnings management, and stock expected returns by using a sample of Chinese listed firms to investigate 22,022 firm–year observations from 1998 to 2018. Our study reveals that an increase in stock liquidity is associated with a decrease in the degree of earnings management. This result is robust to the use of alternative measures when endogeneity concerns are controlled for. Moreover, the findings indicate that the stock liquidity component of earnings management is positively associated with future stock returns in Chinese firms. Our results reveal that the stock liquidity component of short-termism in managerial decisions plays a critical role in determining future stock returns.     

Disclosure quality,price efficiency,and expected returns

Using a composite disclosure quality measure, we examine the effect of disclosure quality on price delay and the effect of price delay determined by disclosure quality on expected returns in the Taiwan stock market. We find that higher disclosure quality can reduce stock price delay through more investor attention and higher stock liquidity after we control for accounting quality variables and consider the endogeneity issue. Furthermore, we show that disclosure quality reduces expected stock returns through the price efficiency channel associated with both investor attention and stock liquidity. Our results indicate that increasing a firm’s standardized information rating by one standard deviation can reduce its expected stock return by 0.63% annually. Taken together, our evidence suggests that regulatory activities enforced to improve public firms’ disclosure quality in the Taiwan stock market can make the stock market more efficient and therefore lower investors’ required return for stocks.     

Option values,stipends and the returns to educational investment

In this paper we use a dynamic model of the returns to educational investment to analyze the flow of students moving through the various stages of an educational system. Dropout and graduation rate are linked to the profitability of an educational stage and thus may be influenced by an appropriate choice of stipend level. To determine the effects of changes in stipends on the output of the educational system we hypothesize a probability distribution of abilities in the population. The parameters of this distribution permit the estimation of the effects of stipends on the graduation rate of each educational stage.     

Tornado activity,house prices,and stock returns

In this paper we investigate the effects of tornado activity on house prices and stock returns in the US. First, using geo-referenced and metropolitan statistical area (MSA)-level data, we find tornado activity to be responsible for a significant drop in house prices. Spillover tornado effects between adjacent MSAs are also detected. Furthermore, our granular analysis provides evidence of tornadoes having a negative impact on stock returns. However, only two sectors seem to contribute to such a negative effect (i.e., consumer discretionary and telecommunications). In a macro-analysis, which relies on aggregate data for the South, West, Midwest and Northeast US regions, we then show that tornado activity generates a significant drop in house prices only in the South and Midwest. In these regions, tornadoes are also responsible for a drop in income. Tornado activity is finally found to positively (negatively) affect stock returns in the Midwest (South). If different sectors are examined, a more heterogeneous picture emerges.     

Firm size,economic risks,and the cross-section of international stock returns

Recent empirical evidence from developed markets indicates a negative relation between value premium and firm size. We find that the value premium in small stocks is consistently priced in the cross-section of international returns, whereas the value premium in big stocks is not. Based on US data, we show that the small-stock value premium is associated with business cycle news and reflects changes in macroeconomic, especially credit market related risks. Our results hold true for regional and global equity markets and remain valid after controlling for firm characteristics and prominent profitability and investment factors.     

Corporate takeovers,stockholder returns and executive rewards

Various motives for making corporate acquisitions have been forwarded in the managerial economics literature. Two that have received a lot of attention are the maximization of stockholder wealth and the maximization of senior management's utility. These two alternative views can lead to different acquisition decisions. The paper examines the returns to senior management and the returns to stockholders following corporate takeovers in the United Kingdom. The evidence suggests that if shareholders profit from takeovers then so do the senior' management. Of more interest, however, is the finding that if acquisitions result in a reduction in stock market value for the acquiring firm, their senior management appear to gain. In particular, senior management remuneration increases substantially after an acquisition. This evidence is consistent with the maximization of senior management's utility being an important motive in many corporate-acquisition decisions.     

Expected market returns: SVIX,realized volatility,and the role of dividends

This note provides a replication of Martin's (Quarterly Journal of Economics, 2017, 132(1), 367–433) finding that the implied volatility measure SVIX predicts US stock market returns up to 12‐month horizons. I find that this result holds for both S&P 500 and CRSP market returns, regardless of whether returns include or exclude dividends. The predictability largely disappears after the SVIX index is replaced by an exponentially weighted moving average measure of realized volatility, suggesting that SVIX holds incremental forward‐looking information compared to realized volatility, despite the high correlation between the two volatility measures.     

Autocorrelation,return horizons,and momentum in stock returns

In this study we examine Lewellen’s (Rev Financ Stud 15:533–563 2002) claim that momentum in stock returns is not due to positive autocorrelation as behavioral models suggest. Using portfolio-specific data, we find the autocovariance component of the momentum profit to be negative, suggesting no return continuations. However, we also find that the autocorrelations calculated from short-term (e.g., monthly) returns are quite different from long-horizon (e.g., annual) autocorrelations. While the first-order autocorrelations of 6– and 12-month returns tend to be negative, the autocorrelations across twelve lags in monthly returns of the industry, size, and B/M portfolios are in general positive. Our results show that these portfolios exhibit return continuations when returns are measured on a monthly basis. Therefore, our finding appears to be consistent with the behavioral models, which suggest positive autocorrelation in stock returns.     

Market index returns,macroeconomic variables,and tax-loss selling

This study provides the most direct macro-level test to date of the tax-loss selling hypothesis as an explanation of the January effect. By examining relationships between macroeconomic variables that should be related to tax-loss selling and market index measures of the January effect, this study provides an approach that addresses the market microstructure problems that are inherent in much of the prior research regarding tax-loss selling. This study also addresses some of the methodological and variable specification concerns in prior macro-level testing, resulting in stronger support for taxloss selling. The authors wish to acknowledge the editor and anonymous referees for helpful comments and suggestions.     

Default-risky bond prices with jumps,liquidity risk and incomplete information

This paper provides a default-risky bond valuation model, which assumes that the issuer’s credit quality, modelled by the intensity of default, is driven by a continuous-time Markov chain. The model accounts for default and liquidity risk as well as incomplete information. A full-information semimartingale representation of a liquid defaultable bond price, which separates three different types of risks—default, interest-rate and credit-quality, is obtained. The illiquidity is modelled as exogenously specified stochastic reduction in the price of the bond, which adds more risks for the investors. A model of a market with partially informed investors, belonging to specific investor classes and having access to discrete information sets about credit quality, was specified. Valuations of defaultable bonds in this market were provided as well as price impacts of the new information releases.      

Hedge funds,fund attributes and risk adjusted returns

We use proprietary data to examine factors that lead hedge fund managers to offer hurdle rates and investigate relative hedge fund performance based on risk-adjusted returns. Using data from 3,571 hedge funds over a 15 year period, we find that funds that do not offer a hurdle rate outperform those that do. Funds offering a high watermark charge substantially higher performance fees. Further, emerging market, fixed income, and funds of funds are significantly more likely to offer a hurdle rate than other types of funds. Performance fees have a positive impact on the likelihood of offering a hurdle rate. Fund leverage and management fees are negatively associated with hurdle rates. The cross-sectional regressions show that funds, which offer a hurdle rate, underperform those that do not. Funds that charge a high performance fee appear to outperform those that charge a relatively low fee. The results are consistent with the view that those managers who wish to improve risk-adjusted returns should not focus on hurdle rates.     

Abnormal returns, risk, and options in large data sets

Large data sets in finance with millions of observations have become widely available. Such data sets enable the construction of reliable semi-parametric estimates of the risk associated with extreme price movements. Our approach is based on semi-parametric statistical extreme value analysis, and compares favorably with the conventional finance normal distribution based approach. It is shown that the efficiency of the estimator of the extreme returns may benefit from high frequency data. Empirical tail shapes are calculated for the German Mark—US Dollar foreign exchange rate, and we use the semi-parametric tail estimates in combination with the empirical distribution function to evaluate the returns on exotic options.     

On the estimation of returns to scale, technical progress and monopolistic markups

A number of theoretical results on estimating returns to scale, technical progress and monopolistic markups are derived when there are multiple outputs and inputs. The choice of value added versus gross output and problems that arise in aggregation across sectors of an economy are also considered. Using US data on manufacturing, evidence is found of increasing returns to scale across all levels of aggregation. Technical progress is typically found to be insignificant implying that economic growth has been driven by increasing returns to scale rather than technical progress. Such findings have important implications for the macroeconomic modeling of economic fluctuations.