The response of the Dollar/Yen exchange rate to economic announcements

The paper examines the impact of major U.S. macroeconomic announcements on the Dollar/Yen exchange rate. We find that these announcements are responsible for most intraday and day-of-the-week volatility patterns in this market and we identify the most important announcements. The initial reaction to a major 8:30 announcement begins around 8:30:10 and lasts until about 8:30:50. A partial price correction is normally observed between 8:31 and 8:32. Price movements after 8:32 are basically independent of those observed earlier although volatility continues to be higher than normal until about 8:55.     

The diversity of high-frequency traders

The regulatory debate concerning high-frequency trading (HFT) emphasizes the importance of distinguishing different HFT strategies and their influence on market quality. Using data from NASDAQ-OMX Stockholm, we compare market-making HFTs to opportunistic HFTs. We find that market makers constitute the lion's share of HFT trading volume (63–72%) and limit order traffic (81–86%). Furthermore, market makers have higher order-to-trade ratios and lower latency than opportunistic HFTs. In a natural experiment based on tick size changes, we find that the activity of market-making HFTs mitigates intraday price volatility.     

Preposterior analysis for option pricing

The second partial derivative of a European-style vanilla option with respect to the current price of the underlying asset—the option gamma—defines a probability density function for the current underlying price. By use of entropy maximization it is possible to obtain an option gamma, from which the associated option pricing formula can be recovered by integration. A number of pricing formulae are obtained in this manner, corresponding to different specifications of the constraints. When the available market information consists solely of a set of traded option prices, the entropic formulation leads to a model-independent calibration procedure. The result thus obtained also allows one to recover the relevant Greeks.     

Foreign news and the structure of co-movement in European equity markets: An intraday analysis

We investigate European equity market volatility responses to foreign macroeconomic surprises. We measure the length of the response and decompose the news effect into direct and indirect components. The latter is induced by volatility transmission between equity markets. We show that 50 percent of the total accumulated impact of US macroeconomic news on the DAX 30 and CAC 40 volatilities is attained after 90 min. We find that the news announcements have significant direct impacts on both European indices but the indirect effect on the French index is stronger than that on the German.     

Stock volatility predictability in bull and bear markets

The recent literature on stock return predictability suggests that it varies substantially across economic states, being strongest during bad economic times. In line with this evidence, we document that stock volatility predictability is also state dependent. In particular, in this paper, we use a large data set of high-frequency data on individual stocks and a few popular time-series volatility models to comprehensively examine how volatility forecastability varies across bull and bear states of the stock market. We find that the volatility forecast horizon is substantially longer when the market is in a bear state than when it is in a bull state. In addition, over all but the shortest horizons, the volatility forecast accuracy is higher when the market is in a bear state. This difference increases as the forecast horizon lengthens. Our study concludes that stock volatility predictability is strongest during bad economic times, proxied by bear market states.     

基于高频数据的股指期货与现货市场波动溢出和信息传导研究

本文利用沪深300指数和当月股指期货连续合约的高频数据,采用非参数方法估计日度股票指数和股指期货的整体波动、连续性波动和跳跃,发现两个市场波动成分存在双向的格兰杰因果关系,但是期货市场的跳跃并不会影响后续股票市场的跳跃。此外,已实现相关系数在股指期货上市初期表现出了较大的变动,整体表现出了较强的联动趋势。最后,日内高频价格之间存在稳定的协整关系,两个市场存在双向的信息传导,股指期货的价格发现功能得到发挥。     

When spread bites fast – Volatility and wide bid-ask spread in a mixed high-frequency and low-frequency environment

This research focuses on the impact High-Frequency Trading has on price volatility when bid-ask spread is wide. The theoretical part introduces a set of equations and presents an Agent Based Model implemented via a computer-based simulation. The wide spread leads to the appearance of unusual phenomena caused by the relative speed difference between the fast and slow traders. The latter agents tend to quote limit orders that look irrational, as they are distant more than one tick from the top-of-book. The same relative speed difference causes slow traders to post market orders that execute at price worse than originally intended. Both these abnormal orders tend to increase local volatility. Other results found by the simulation are an increase in global volatility (computed both as the difference of maximum less minimum price and as standard deviation of price distribution) and in volatility at sub-second timescales. These occurrences penalise slower traders and affect market stability. All the results are consistent both under quiet and stressed market conditions. The results found are then compared with audit trail data to verify the soundness of theory against practice.     

短期利率波动测度与预测:基于混频宏观-短期利率模型

经验研究表明宏观经济对识别短期利率及其波动现象具有重要影响。为合理引入宏观信息并精确拟合与预测短期利率波动行为,本文提出一种包含宏观因子的混频短期利率模型,即BHK-MIDAS模型。基于中国宏观及利率数据信息的研究结果表明:与传统短期利率模型相比,BHK-MIDAS模型具有更优的样本内拟合效果;相对于货币政策指标而言,宏观基本面与通胀指标对短期利率波动的贡献更大;进一步地,混频模型还可以识别出受宏观因子显著影响的短期利率波动的长期成分;特别地,BHK-MIDAS模型在短期利率波动样本外预测方面的良好表现,充分说明宏观因子在识别及预期短期利率波动行为方面的重要贡献。     

Quadratic Hawkes processes for financial prices

We introduce and establish the main properties of QHawkes (‘Quadratic’ Hawkes) models. QHawkes models generalize the Hawkes price models introduced in Bacry and Muzy [Quant. Finance, 2014, 14(7), 1147–1166], by allowing feedback effects in the jump intensity that are linear and quadratic in past returns. Our model exhibits two main properties that we believe are crucial in the modelling and the understanding of the volatility process: first, the model is time-reversal asymmetric, similar to financial markets whose time evolution has a preferred direction. Second, it generates a multiplicative, fat-tailed volatility process, that we characterize in detail in the case of exponentially decaying kernels, and which is linked to Pearson diffusions in the continuous limit. Several other interesting properties of QHawkes processes are discussed, in particular the fact that they can generate long memory without necessarily being at the critical point. A non-parametric fit of the QHawkes model on NYSE stock data shows that the off-diagonal component of the quadratic kernel indeed has a structure that standard Hawkes models fail to reproduce. We provide numerical simulations of our calibrated QHawkes model which is indeed seen to reproduce, with only a small amount of quadratic non-linearity, the correct magnitude of fat-tails and time reversal asymmetry seen in empirical time series.     

Do corporate insiders circumvent insider trading regulations? The case of stock repurchases

We use calculated values of standardized abnormal insider trading activity to investigate for patterns of unusual insider activity around fixed-price and Dutch auction repurchase announcements. Firms are classified according to whether the repurchase is signaling information about future cash flows, about the distribution of excess free cash flows, or about management's attempts to maintain control in the presence of a takeover. We find below normal levels of sales well before the event and above normal levels of sales after the event. This tendency is strongest for fixed-price offers and for firm's conveying information about future cash flows, and is absent for firms involved in takeovers. No evidence exists of abnormal levels of purchases before or after the event. We interpret the evidence as consistent with insiders successfully circumventing policies and regulations designed to prevent the exploitation of private information by timing the pattern of their security sales.     

Daily Closing Inside Spreads and Trading Volumes Around Earnings Announcements

This paper examines the determinants of inside spreads and their behaviour around corporate earning announcement dates, for a sample of UK firms over the period 1986–94. The paper finds that closing daily inside spreads are affected by order processing costs (proxied by trading volumes), inventory control costs (trading volumes and return variability) and asymmetric information (unusually high trading volumes). Inside spreads start to narrow 15 days before an earnings announcement, and narrow further by the end of the announcement day. We also identify a puzzling phenomenon. There is only a 'sluggish' recovery of spreads after the announcement: inside spreads continue to remain at relatively narrow levels, and take up to 90 days to recover to their pre–announcement width.