An empirical examination of the impact of market microstructure changes on the determinants of option bid-ask spreads

This paper examines the determinants of bid-ask spreads in the Australian Options Market before and after it switched from a quote-driven floor-traded market to an order-driven screen-traded market. This study reports that both put and call option bid-ask spreads are positively related to the option's value, its remaining term-to-maturity, its absolute hedge ratio and the volatility of returns from the underlying asset and negatively related to the level of trading activity in that option series. The study also reports that spreads are generally less when market makers are obliged to maintain continuous quotes in the market. The paper also finds that following the change in trading regime, both call and put option spreads became more sensitive to the absolute value of the option's delta. This finding is consistent with previous theoretical and empirical work from equities markets that has suggested that a switch to an electronic trading regime results in an increase in the adverse selection component of the bid-ask spread. There is also some limited evidence that suggests that the switch to electronic trading resulted in call option spreads being less sensitive to the return volatility of the underlying asset but more sensitive to the option's price.     

Volume,volatility and information linkages in the stock and option markets

This paper examines the relationship between option trading activity and stock market volatility. Although the option market is uniquely suited for trading on volatility information, there is little analysis on how trading activity in this market is linked to stock price volatility. The bulk of the discussion tends to focus on whether trading activity in the stock market is informative about stock volatility. To analyze the information in option trading activity for stock market volatility, a sample of 15 stocks with the highest option trading volume is selected. For each stock, it is noted that the trading activities in the put and call option markets have significant explanatory power for stock market volatility. In addition, the results indicate that the call option trading activity has a stronger impact on stock volatility compared with that of the put options. Our results demonstrate that information and sentiment in the option market is useful for the estimation of stock market volatility. Also, the significance of the effects of option trading activity on stock price volatility is observed to be comparable to that of stock market trading activity. Furthermore, the persistence and asymmetric effects in the volatility of some stocks tend to disappear once option trading activity is taken into account.     

Investor Attention and Time‐varying Comovements

This paper analyses the effect of an increase in market‐wide uncertainty on information flow and asset price comovements. We use the daily realised volatility of the 30‐year treasury bond futures to assess macroeconomic shocks that affect market‐wide uncertainty. We use the ratio of a stock's idiosyncratic realised volatility with respect to the S&P500 futures relative to its total realised volatility to capture the asset price comovement with the market. We find that market volatility and the comovement of individual stocks with the market increase contemporaneously with the arrival of market‐wide macroeconomic shocks, but decrease significantly in the following five trading days. This pattern supports the hypothesis that investors shift their (limited) attention to processing market‐level information following an increase in market‐wide uncertainty and then subsequently divert their attention back to asset‐specific information.     

A trading strategy based on Callable Bull/Bear Contracts

The Callable Bull/Bear Contract is a barrier options contract recently introduced to the Hong Kong market. In this study, we propose a trading strategy that defines the entry point and exit point using information on the contract's call price and mandatory call event. Using data on contracts based on the Hong Kong Hang Seng Index, it is shown that the proposed trading strategy, on average, yields some decent trading returns that vary quite substantially across individual trades. Exploratory analyses indicate that trading returns are associated with volatility observed during a contract's lifespan and, to a lesser extent, with volatility in the pre-issuance period. Further, an issuer's relative issuing frequency may bear some implications for the trading strategy's performance.     

How does the call market method affect price efficiency? Evidence from the Singapore Stock Market

On August 21, 2000, the Singapore Exchange (SGX) adopted the call market method to open and close the market while the remainder of the day’s trading continued to rely on the continuous auction method. The call method significantly improved the price discovery process and market quality. A positive spillover effect is observed from the opening and closing calls. Day-end price manipulation also declined after the introduction of the call market method. However, the beneficial impact from the call market method is asymmetric, benefiting liquid stocks more than illiquid stocks.     

Price-Formation Process of an Emerging Futures Market: Call Auction Versus Continuous Auction

This study assesses the market qualities of alternative price-formation processes for an emerging futures market—the Taiwan futures market. In 2002, the price formation process in the market changed during the period of trade between call auction and continuous auction. The performances of call auction and continuous auction are compared using intraday data. Empirical results show that the market is more liquid, and volatility is slightly lower, under continuous auction than under call auction. Also, there is robust evidence that continuous auction improves informative efficiency. The study suggests that for an emerging futures market like that of Taiwan, continuous auction offers a better trading environment for futures trading. In addition to demonstrating the virtue of continuous auction, this study also finds that the asymmetry in volatility is related to the price formation process. The asymmetry effect exists under continuous auction, but not under call auction.     

Volatility spreads and earnings announcement returns

Prior research documents that volatility spreads predict stock returns. If the trading activity of informed investors is an important driver of volatility spreads, then the predictability of stock returns should be more pronounced during major information events. This paper investigates whether the predictability of equity returns by volatility spreads is stronger during earnings announcements. Volatility spreads are measured by the implied volatility differences between pairs of strike price and expiration date matched put and call options and capture price pressures in the option market. During a two-day earnings announcement window, the abnormal returns to the quintile that includes stocks with relatively expensive call options is more than 1.5% greater than the abnormal returns to the quintile that includes stocks with relatively expensive put options. This result is robust after measuring volatility spreads in alternative ways and controlling for firm characteristics and lagged equity returns. The degree of announcement return predictability is stronger when volatility spreads are measured using more liquid options, the information environment is more asymmetric, and stock liquidity is low.     

Intraday futures market behaviour around major scheduled macroeconomic announcements: Australian evidence

This paper examines intraday futures market behaviour around major scheduled macroeconomic information announcements on the Sydney Futures Exchange (SFE). Prior literature analysing intraday price behaviour around announcements is extended to trading volume and quoted bid–ask spreads. The analysis of price volatility, trading volume and quoted bid–ask spreads indicates that the majority of adjustment to new information occurs rapidly, within 240 seconds of the scheduled time for major announcements, with some evidence of abnormal activity prior to announcements. Analysis of quoted bid–ask spreads suggests that they significantly widen in the 20 seconds prior to announcements and remain significantly wider for 30 seconds following announcements. The increase in quoted spreads is related to both expected and unexpected volatility, implying that market participants increase quoted spreads around information announcements as a consequence of adverse selection costs.     

When machines read the news: Using automated text analytics to quantify high frequency news-implied market reactions

We examine high-frequency market reactions to an intraday stock-specific news flow. Using unique pre-processed data from an automated news analytics tool based on linguistic pattern recognition we exploit information on the indicated relevance, novelty and direction of company-specific news. Employing a high-frequency VAR model based on 20 s data of a cross-section of stocks traded at the London Stock Exchange we find distinct responses in returns, volatility, trading volumes and bid-ask spreads due to news arrivals. We show that a classification of news according to indicated relevance is crucial to filter out noise and to identify significant effects. Moreover, sentiment indicators have predictability for future price trends though the profitability of news-implied trading is deteriorated by increased bid-ask spreads.     

The information content of ETF options

We examine the information content of China's Shanghai Stock Exchange (SSE) 50 ETF options introduced in 2015. Trading volume and implied volatilities of calls versus puts differ markedly: trading volume is consistently higher for calls, and implied volatility is higher for puts. Put-call volume and implied volatility ratios are not good predictors of future SSE 50 returns. Implied volatility follows a right-skewed smirk across strike prices, indicating a tendency among option traders to turn bullish and expect the stock market to recover from the June 2015 market crash. The options market dominates the price discovery process, with an average information leadership share of 67%. Our price discovery results persist during the COVID outbreak.     

It's SHO Time! Short-Sale Price Tests and Market Quality

We examine the effects of the Securities and Exchange Commission (SEC)-mandated temporary suspension of short-sale price tests for a set of Pilot securities. While short-selling activity increases both for NYSE- and Nasdaq-listed Pilot stocks, returns and volatility at the daily level are unaffected. NYSE-listed Pilot stocks experience more symmetric trading patterns and a slight increase in spreads and intraday volatility after the suspension while there is a smaller effect on market quality for Nasdaq-listed Pilot stocks. The results suggest that the effect of the price tests on market quality can largely be attributed to distortions in order flow created by the price tests themselves.     

Differently motivated exchange traded fund trading activities and the volatility of the underlying index

This paper examines the correlations between two types of a market index's volatility and three trading motives of the index's exchange traded funds (ETFs). We find that ETF trading driven by belief dispersion is highly correlated with both the variance in efficient price innovations (VEPI) and the index's total volatility. Privately informed ETF trading is closely connected to the VEPI but not the total volatility, while liquidity ETF trading explains the total volatility but has little power in explaining the VEPI. Moreover, the leading ETF dominates smaller ETFs in explaining both types of volatility and often has more explanatory power than control variables.     

Non-trading,market making,and estimates of stock price volatility

We examine the effects of market making and intermittent trading on estimates of stock price volatility. When observed price changes are correctly tied to a stock's true price dynamics, it is found that non-trading per se causes a loss of efficiency but no bias in traditional volatility estimates. Non-trading induces substancial inefficiency in the extreme value estimator of volatility which it biases downward. Market making's effects add to the non-trading induced inefficiency in the traditional estimator, while information trading causes a downward bias, and liquidity trading a potentially removable upward bias, in that estimator.     

Impact of the introduction of call auction on price discovery: Evidence from the Indian stock market using high-frequency data

Call markets are claimed to aggregate information and facilitate price discovery where continuous markets may fail. The impact of the introduction of call auction has not been found uniformly beneficial, possibly due to poor design or due to ‘thick market externalities’. This paper examines the reintroduction of opening call auction at the National Stock Exchange of India in 2010. The results suggest that the auctions attract very little volume, the intraday pattern of volume and volatility in the continuous market remains unchanged and a large fraction of price discovery, measured by the Weighted Price Contribution, still takes place in the first 15 min of continuous market. However, the market synchronicity has improved after the introduction of the auction. Our findings suggest that the ability to attract volume in the call auction for effective price discovery depends on the institutional settings and the characteristics of liquidity supply in the market.     

The impact of lunchtime closure on market behaviour: evidence from the Sydney Futures Exchange

This paper examines the impact of lunchtime closure on market behaviour. Between May and September, 1994 the Sydney Futures Exchange trialed lunchtime trading. The trial provides a unique natural laboratory experiment for examining the impact of lunchtime closure. The analysis reported in this paper documents abnormally high bid ask spreads, price volatility and trading volume on re‐opening of the market following lunchtime closure. These results confirm that closure has an impact on trading activity, and are consistent with the effects of strategic informed trading, a loss in price discovery and/or trading associated with risk transfer. An abnormal increase in trading volume prior to lunchtime closure is also documented, providing unambiguous evidence of trading activity motivated by risk transfer. Overall these results imply that lunchtime closure disrupts trading activity and reduces market quality by imposing additional costs on market participants.     

The impact of lunchtime closure on market behaviour: evidence from the Sydney Futures Exchange

This paper examines the impact of lunchtime closure on market behaviour. Between May and September, 1994 the Sydney Futures Exchange trialed lunchtime trading. The trial provides a unique natural laboratory experiment for examining the impact of lunchtime closure. The analysis reported in this paper documents abnormally high bid ask spreads, price volatility and trading volume on re‐opening of the market following lunchtime closure. These results confirm that closure has an impact on trading activity, and are consistent with the effects of strategic informed trading, a loss in price discovery and/or trading associated with risk transfer. An abnormal increase in trading volume prior to lunchtime closure is also documented, providing unambiguous evidence of trading activity motivated by risk transfer. Overall these results imply that lunchtime closure disrupts trading activity and reduces market quality by imposing additional costs on market participants.     

Volatility increases Subsequent to NYSE and AMEX Stock Splits

The post-split increase in daily returns volatility is less for AMEX stocks than for NYSE stocks. The exchange trading location is a significant factor in explaining the volatility shift even after stock price and firm size are considered. Furthermore, when measured on a weekly basis, there is no increase in AMEX stocks' returns volatility. These results suggest that measurement errors created by bid-ask spreads and the 1/8 effect, and also one or more of the elements that make the NYSE different from the AMEX, explain why the estimated volatility of daily stock returns increases after the ex split date.     

The Effect of Option Listing on Bid-Ask Spreads,Price Volatility,and Trading Activity of the Underlying OTC Stocks

This paper examines the changes in spreads, price volatility, and trading activity surrounding option listing for a sample of 144 OTC stocks. For this sample, both price volatility and volume increase, but the evidence on spreads is mixed. The increase in price volatility is attributed primarily to an increase in residual return variances. Furthermore, price volatility increases even after controlling for volume, insider trading, and spreads. Although these variables do not fully explain the causes for the increase in price volatility after option listing, the results suggest that liquidity trading or volume has a stronger effect on price volatility than insider trading. This study also finds that both the number of trades and institutional holdings show substantial increases, which are supportive of the notion that listing of options on OTC stocks attracts more attention.     

Trading frequency and the efficiency of price discovery in a non-dealer market

The increasing popularity of non-dealer security markets that offer automated, computer-based, continuous trading reflects a presumption that institutionally-set trading sessions are economically obsolete. This theoretical paper investigates the effect of the trading frequency, a key feature of the trading mechanism, on the efficiency of price discovery in a non-dealer market. By tracing the market pricing error to the correlation structures of arriving information and pricing errors of individual traders, the effect of diverging expectations on error-based and overall return volatility is isolated. The analysis reveals that, due to a portfolio effect, an increase in the trading time interval has contradictory effects on the portion of return volatility stemming from pricing errors. The greater accumulation of information increases error-based return volatility, but the greater volume and number of traders per session have the opposite effect. The net effect on overall return volatility can go either way. It is found that the return volatility of heavily traded securities is likely to be minimized under continuous trading, but that of thinly traded securities may be minimized under discrete trading at moderate time intervals. The latter is more likely to occur the greater is the divergence of expectations among traders. These findings challenge the presumption that automated continuous trading in a non-dealer market is more efficient than discrete trading for all securities, regardless of trading volume. The findings are applicable to all economies, but have special importance for developing countries where typically a single market is dominated by small issues and a low volume of trade. As a by-product of the analysis, it is shown how to correct the biased estimate of inter-session price volatility when observations are less frequent than the trading sessions themselves.     

Trading Patterns and Prices in the Interbank Foreign Exchange Market

The behavior of quote arrivals and bid-ask spreads is examined for continuously recorded deutsche mark-dollar exchange rate data over time, across locations, and by market participants. A pattern in the intraday spread and intensity of market activity over time is uncovered and related to theories of trading patterns. Models for the conditional mean and variance of returns and bid-ask spreads indicate volatility clustering at high frequencies. The proposition that trading intensity has an independent effect on returns volatility is rejected, but holds for spread volatility. Conditional returns volatility is increasing in the size of the spread.