A Likelihood Ratio Test of Price Volatilities: Comparing Stock Index Spot and Futures

This paper uses three methods to estimate the price volatility of two stock market indexes and their corresponding futures contracts. The classic variance measure of volatility is supplemented with two newer measures, derived from the Garman-Klass and Ball-Torous estimators. A likelihood ratio test is used to compare the classic variance measure of price volatilities of two stock market indexes and their corresponding futures contracts during the bull market of the 1980s. The stock market volatilities of the Standard & Poor's 500 (S&P 500) and New York Stock Exchange (NYSE) indexes were found to be significantly lower than their respective futures price volatilities. Since information may flow faster in the futures markets than in the corresponding stock market, our results support Ross's information-volatility hypothesis. It was also noted that the NYSE spot volatility was lower than the S&P 500 spot volatility. If the rate of information flow and firm size are positively related, then the lower NYSE spot volatility is explained by the size effect. The futures price volatilities for the two indexes were insignificantly different from each other. With stock index spot-futures price correlations approaching unity, one implication of our results for index futures activity is that smaller positions in futures contracts may suffice to achieve hedging or arbitrage goals.     

Trading activity and price discovery in Bitcoin futures markets

This study examines the impact of trading activities on price discovery in the Bitcoin futures markets. We find that trades of hedgers are positively correlated with the modified information shares in both CME and CBOE futures markets, suggesting that their trading promotes futures market efficiency. Retailers’ trading activity relates negatively to the price discovery of the CME Bitcoin futures and thus destabilizes the market. Speculators exert positive (negative) impact on the price discovery in the CME (CBOE) Bitcoin futures. Our finding that CME’s Bitcoin futures exhibit superior price discovery than CBOE’s provides plausible justification for CBOE’s decision in March 2019 to suspend further listings of Bitcoin futures contracts.     

The price discovery role of day traders in futures market: Evidence from different types of day traders

Using proprietary account-level transaction data in the futures market where day traders are self-declared ex ante, this study investigates whether day traders enhance price discovery at the market level. From a natural classification of day traders, we find that heterogeneous day traders have differential effects on price discovery. Self-declared day traders, who benefit from low margin requirement, do not improve price discovery measured by information share. In contrast, non-declared traders, who are not self-declared as day traders, improve price discovery. Their positive impacts on price discovery are particularly significant during periods of high volatility and arrival of new information. Overall, a margin stimulating policy may encourage more day trading, but may also attract overconfident investors, especially inexperienced ones, and who do not enhance price discovery.     

"Marking-to-Market" and Treasury-Bill Futures Prices: Some Empirical Evidence

Financial economists have not found empirical evidence of a “marking‐to‐market” effect in Treasury‐bill futures contracts, despite a firm theoretical basis for its existence. Therefore, we speculate that confounding effects, possibly due to liquidity preferences, influence futures‐forward price spreads. By using an empirical specification that allows for both effects, we present empirical evidence that Treasury‐bill futures‐forward price spreads are sensitive to the volatility of the underlying commodity in ways predicted by the theory of the marking‐to‐market effect.     

Price discovery in bitcoin futures

This paper studies the contribution of the newly launched future contracts to the bitcoin price discovery process. Using well-established methodologies in the literature of the evaluation of price discovery in financial markets, we find evidence that, although the volume of bitcoins traded in the decentralized spot market overwhelms that of the futures market, the latter plays a more important role in incorporating new information about the value of bitcoin. Our empirical investigation also provides evidence of strong bi-directional dependence in the intraday volatility of the spot and futures markets.     

ARE PRICE LIMITS EFFECTIVE? EVIDENCE FROM THE ISTANBUL STOCK EXCHANGE

There is considerable discussion about controlling volatility by imposing price limits on asset prices. We examine the effects of price limits on a stock market by testing the volatility spillover, delayed price discovery, and trading interference hypotheses in a leading emerging market, the Istanbul Stock Exchange, which has a unique market microstructure as related to price limits. Our results support the volatility spillover, delayed price discovery, and trading interference hypotheses. We also show price locks at limits provide significantly stronger evidence regarding the effects of price limits than limit moves only. Finally, price limits have a significant effect on the stock market, casting doubt on their effectiveness.     

A Tale of Two Index Futures: The Intraday Price Discovery and Volatility Transmission Processes Between the China Financial Futures Exchange and the Singapore Exchange

This is the first study to examine the intraday price discovery and volatility transmission processes between the Singapore Exchange and the China Financial Futures Exchange. Using one- and five-minute high-frequency data from May to November 2011, the authors find that the Chinese Securities Index 300 index futures dominate Singapore's A50 index futures in both intraday price discovery and intraday volatility transmission. However, A50 futures contracts also make a substantial contribution (26-37 percent) to the price discovery process. These results have important implications for both traders and policymakers.     

Price limit bands,asymmetric volatility and stock market anomalies: Evidence from emerging markets

I investigate the effects of imposing different bands of price limits on stock returns and volatility in the Egyptian (EGX), Thai (SET) and Korean (KRX) stock exchanges. In addition, the paper examines whether the switch from narrow price limits (NPL) to wider price limits (WPL) structurally alters volatility and the day of the week anomaly. Using the extended EGARCH and PARCH asymmetric volatility models, I found that the switch from NPL to WPL structurally altered both asymmetric volatility and the day of the week anomaly in the EGX, SET and KRX. I argue that the price discovery mechanism is disrupted due to the switch as closing prices do not fully reflect all information arrived in the market when prices hit the limits and that is reflected on volatility and market efficiency.     

Volatility and trading activity following changes in the size of futures contracts

This paper has two purposes. First, we examine the relationship between daily price volatility and trading activity one year before and after a change in contract size by examining the results of contract splits in the Australian share price index futures and the U.K. FTSE-100 futures contracts and a reverse contract split in the Australian Bank Bill Acceptance futures contract. Second, we evaluate the effect of the change in contract size on the use of the particular futures market. We find that after a contract size change, the change in total trading frequency has the power to explain the change in daily price volatility. Specifically, after a contract split, trading frequency increased, resulting in increased daily price volatility, and vice versa after a reverse contract split. Most of the average trade size variable has an immaterial impact on price volatility. However, decomposing the total trading frequency into four trade size classes, we find that the trading frequency for small and large trade size categories are highly significant in explaining changes in daily price volatility after the contract splits. Finally, we find the change in contract size for each futures market was successful because within three years following the change, the adjusted trading volume and open interest surpassed the levels prior to the change and have continued to increase thereafter.     

The effectiveness of position limits: Evidence from the foreign exchange futures markets

This study considers the effects of the relative size of hedger and speculator open interests and the potential impact of implementing position limits on the price discovery process in both JPY–USD and EUR–USD futures markets. Hedging trading exerts a negative impact, regardless of its size, on price discovery in futures markets. Hedgers are less likely to be information motivated, so their trading uniformly delays the price discovery process. However, there is a positive and nonlinear impact of speculators’ trade size on price discovery, the contribution of which depends on the relative size of the speculative open interest. Contrary to conventional wisdom among regulators, speculative trading does not harm the market in terms of market efficiency; as long as the percentage of speculators’ open interest is below an endogenously determined threshold (approximately 20% for EUR–USD and 16.3% for JPY–USD), speculative trading even improves futures market efficiency.     

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。     

The Influence of Information Arrival on Market Microstructure: Evidence from Three Related Markets

This study examines the influence of information arrival on market microstructure for the MMI, NYSE, and S&P 500 stock index futures markets, with special emphasis on the effects of opening and closing of trading and expiration of contracts on price movements and trading activities. The results of the examination show that although the opening of the (MMI) futures market is associated with higher volatility, it is when the spot market opens that volatility reaches its highest level. Similarly, the closing of the futures markets, though more volatile, is not as volatile as the closing of the spot markets. Trading patterns, on the other hand, are distinct from volatility. For MMI, trading declines consistently after the close of the spot market. In contrast, the NYSE and S&P 500 continue to trade and reach a peak at the close of the futures markets. Expiration effects are evidenced by the increase in volatility and trading near the closing of the MMI and the spillover to the NYSE and S&P 500. In sharp contrast, the expirations of the NYSE and S&P 500 are only assooiated with decrease in trading, suggesting that efforts to dampen volatility by changing expiration days from Friday to Thursday and shifting settlement price from Friday close to Friday open, have been successful.     

The Reaction of Coffee Futures Price Volatility to Crop Reports

Analysis of prices and volatility plays an important role in coffee market, especially for developing countries, whose small producers and economies rely heavily on income generated by coffee trade. This study explores the impact of coffee crop reports on price volatility for coffee futures contracts during 2004–2014. Overall, results indicate that crop reports generally affect price volatility. The impact is particularly stronger when they provide information following the flowering periods in Colombia, Brazil, and Vietnam, world’s major producers.     

国内外黄金市场价格间的联动关系稳定吗?——基于外部冲击视角的分析

在全球金融市场不断开放和融合的大背景下,黄金市场不但与外部市场频繁互动,其系统内部的联动关系也变得极为多元和复杂,黄金市场间的价格联动反映了信息和风险在不同市场间的传递过程。黄金价格通常会受到外部因素干扰而产生波动,但市场间的联动关系是否会因此而改变是值得重点关注的问题,黄金市场功能的有效性及稳固的市场关系是投资者利用全球黄金市场进行对冲和避险的先决条件,同时也关系到整个金融市场的稳定性。本文将研究重点聚焦于黄金市场内部,在研究中外各主要黄金市场间动态相关性和波动溢出效应的同时引入外部冲击以检验不同因素对黄金期货、现货市场间联动关系的影响从而探讨国内外黄金市场间价格联动的稳定性问题。结果表明:中国与全球主要黄金期货、现货市场间整体上保持了正相关关系,同时与各主要黄金市场间均存在显著的波动溢出效应。在一般市场条件下,外部冲击并没有显著改变中国与全球主要黄金期货、现货市场间的联动关系,表明黄金市场内部的价格联动具有较强的稳定性。     

股指期货市场操纵与价格发现功能的关系研究

股指期货市场操纵会影响股指期货市场的价格发现功能,同样地,股指期货市场的价格发现功能也会影响股指期货市场的操纵行为。本文在理论探讨的基础上,利用股指期货主力合约及对应的沪深300指数高频数据对市场操纵行为进行实证分析。研究结果表明,当操纵嫌疑只存在于期货市场时,股指期货市场的价格发现功能将会减弱;当操纵嫌疑存在于期货、现货两个市场时,股指期货市场的价格发现功能相对会增强。而且,当股指期货市场价格发现功能较强时,市场操纵的难度和成本都将下降。当前中国股指期货市场的操纵行为可能主要局限于某些个别的、离散的交易日内,系统地通过操纵现货指数来操纵期货市场的可能性较低。     

股指期货是股灾的“幕后推手”吗——基于2015年股灾期间沪深300股指期货高频数据实证分析

选取2015年6月15日至8月26日股灾期间沪深300股指期货与沪深300指数5分钟高频数据,通过E-G两步协整检验、格兰杰因果检验、脉冲响应模型等,对股灾期间股指期货市场价格发现功能及波动溢出效应进行实证研究.结果表明:股灾期间沪深300股指期货仍具备价格发现功能,但存在对现货市场的单向波动溢出,具有一定的"助跌"效应.     

Prospect theory and the effectiveness of price limits

Assuming that traders are risk-neutral, Brennan (1986) shows that price limits are effective in improving the efficiency of futures contracts with limited accessibility to information because they obscure the exact loss when they are triggered. However, Brennan's (1986) model fails to explain why price limits also exist in contracts with abundant information like those of financial futures. We show that when traders are loss-averse, the effectiveness of price limits is strengthened even in the presence of precise information. Thus, our analysis provides a theoretical foundation explaining why price limits can be useful when market participants are not fully rational.     

Intraday Price Formation in U.S. Equity Index Markets

The market for U.S. equity indexes presently comprises floor‐traded index futures contracts, exchange‐traded funds (ETFs), electronically traded, small‐denomination futures contracts (E‐minis), and sector ETFs that decompose the S&P 500 index into component industry portfolios. This paper empirically investigates price discovery in this environment. For the S&P 500 and Nasdaq‐100 indexes, most of the price discovery occurs in the E‐mini market. For the S&P 400 MidCap index, price discovery is shared between the regular futures contract and the ETF. The S&P 500 ETF contributes markedly to price discovery in the sector ETFs, but there are only minor effects in the reverse direction.     

Price limit performance: evidence from transactions data and the limit order book

In recent years, organized stock exchanges with daily price limits adopted wider limits as narrower limits were criticized for jeopardizing market efficiency. This study examines the impact of a wide price limit on price discovery processes, using data from the Kuala Lumpur Stock Exchange. Specifically, examined is the impact of daily price limits on (i) information asymmetry; (ii) arrival rates of informed traders; and (iii) order imbalance. Using both trade-to-trade transaction data and the limit order book, we compile evidence that price limits do not improve information asymmetry, delays the arrival of informed traders, and exacerbates order imbalance. These results suggest that price limits on individual securities do not improve price discovery processes but impose serious costs even when the limit band is as wide as 30%.     

Price discovery and volatility spillovers in index futures markets: Some evidence from Mexico

This paper investigates the hypotheses that the recently established Mexican stock index futures market effectively serves the price discovery function, and that the introduction of futures trading has provoked volatility in the underlying spot market. We test both hypotheses simultaneously with daily data from Mexico in the context of a modified EGARCH model that also incorporates possible cointegration between the futures and spot markets. The evidence supports both hypotheses, suggesting that the futures market in Mexico is a useful price discovery vehicle, although futures trading has also been a source of instability for the spot market. Several managerial implications are derived and discussed.