On the Magnet Effect of Price Limits

The ‘magnet’ or ‘gravitational’ effect hypothesis asserts that, when trading halts are rule‐based, investors concerned with a likely impediment to trade advance trades in time. This behaviour actually pushes prices further towards the limit. Empirical studies about the magnet effect are scarce, most likely because of the unavailability of data on rule‐based halts. In this paper, we use a large database from the Spanish Stock Exchange (SSE), which combines intraday stock specific price limits and short‐lived rule‐based call auctions to stabilise prices, to test this hypothesis. The SSE is particularly well suited to test the magnet effect hypothesis since trading halts are price‐triggered and, therefore, predictable to some extent. Still, the SSE microstructure presents two particularities: (i) a limit‐hit triggers an automatic switch to an alternative trading mechanism, a call auction, rather than a pure halt; (ii) the trading halt only lasts 5 minutes. We find that, even when prices are within a very short distance to the price limits, the probability of observing a limit‐hit is unexpectedly low. Additionally, prices either initiate reversion (non limit‐hit days) or slow down gradually (limit‐hit days) as they come near the intraday limits. Finally, the most aggressive traders progressively become more patient as prices approach the limits. Therefore, both the price patterns and the trading behaviour reported near the limits do not agree with the price limits acting as magnetic fields. Consequently, we conclude that the switching mechanism implemented in the SSE does not induce traders to advance their trading programs in time.     

The magnet effect of price limits: A logit approach

We investigate the magnet effect of price limits using transaction data from the Taiwan Stock Exchange. A logit model incorporates explanatory variables from microstructure literature and reveals that the conditional probability of a price increase (decrease) increases significantly when the price approaches the upper (lower) price limit, in support of the magnet effect. Our approach recognizes when the magnet effect starts to emerge and identifies possible determinants of magnet effect. The probability of information-based trading has a significant impact on the magnet effect for lower price limits.     

Price Limit Performance: Evidence from the Tokyo Stock Exchange

Price limit advocates claim that price limits decrease stock price volatility, counter overreaction, and do not interfere with trading activity. Conversely, price limit critics claim that price limits cause higher volatility levels on subsequent days (volatility spillover hypothesis), prevent prices from efficiently reaching their equilibrium level (delayed price discovery hypothesis), and interfere with trading due to limitations imposed by price limits (trading interference hypothesis). Empirical research does not provide conclusive support for either positions. We examine the Tokyo Stock Exchange price limit system to test these hypotheses. Our evidence supports all three hypotheses suggesting that price limits may be ineffective.     

The effect of price limits on intraday volatility and information asymmetry

We investigate the effect of price limits on intra-day volatility and information asymmetry using transactions data from the Taiwan Stock Exchange. Proponents of price limits argue that they provide an opportunity for investors to reevaluate market information and make more rational trading decisions. We identify three different limit hits – closing, single, and consecutive – and hypothesize that only the consecutive limit hits are likely to provide such an opportunity, namely, to counter investor overreaction (volatility hypothesis) and to enhance information revelation (information asymmetry hypothesis). Our empirical evidence supports the volatility hypothesis. Our findings generate important policy implications for stock markets that have price limits.     

A new paradigm for forecasting security returns in a market regulated by price limits

Numerous futures markets in the US and many stock markets around the world set a “limit” price before each trading session, based on the settlement price at the end of the previous trading day. Price limits are boundaries set by market regulators to restrict large daily fluctuations in the price of securities. Once the return limit is triggered, traders cannot observe the equilibrium return that would have prevailed in the absence of such regulation. We develop an innovative approach for forecasting security returns (and prices) in a market regulated by price limits. Our forecasting model allows for multiple limit-hits. The model is robust, straightforward and easy for practitioners to use. A few numerical predictions are provided for hypothetical securities, and for seven traded futures contracts.     

Lower tick sizes and futures pricing efficiency: evidence from the emerging Malaysian market

We provide robust evidence of the impact on spot market liquidity and the pricing efficiency of FBM-FKLI index futures following the introduction of lower tick sizes for the stocks listed in the Bursa Malaysia. Our findings show a significant increase in unexpected trading volume and the speed of mean reversion of the futures mispricing. We find that the increase in the unexpected trading volume of the underlying stocks helps in reducing inter-market price discrepancies. The findings offer new evidence that lowering of tick sizes improves pricing efficiency in the Malaysian futures market.

     

Is the Electronic Open Limit Order Book Inevitable?

Under fairly general conditions, the article derives the equilibrium price schedule determined by the bids and offers in an open limit order book. The analysis shows: (1) the order book has a small-trade positive bid-ask spread, and limit orders profit from small trades; (2) the electronic exchange provides as much liquidity as possible in extreme situations; (3) the limit order book does not invite competition from third market dealers, while other trading institutions do; (4) If an entering exchange earns nonnegative trading profits, the consolidated price schedule matches the limit order book price schedule.     

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.     

The effect of a closing call auction on market quality and trading strategies

We study the effects of the introduction of a closing auction (CA) on the microstructure on the continuous trading phase in Borsa Italiana and Paris Bourse. We postulate and compare several empirical predictions based on both standard Kyle-type models and more recent models of limit order book. We find that while the CA has no effect during most of the day, its effect on the last minutes of trading is dramatic. We document a sharp decline in volume, associated with a significant reduction in spread and volatility, and an increase in aggressiveness of liquidity suppliers during the last minutes. We show that the differences in the Reference Price algorithm between Milan and Paris have a significant effect: the CA attracts greater volumes when the Reference Price is equated to the CA price.     

How do individual investors trade?

This paper examines how high-frequency trading decisions of individual investors are influenced by past price changes. Specifically, we address the question as to whether decisions to open or close a position are different when investors already hold a position compared with when they do not. Based on a unique data set from an electronic foreign exchange trading platform, OANDA FXTrade, we find that investors’ future order flow is (significantly) driven by past price movements and that these predictive patterns last up to several hours. This observation clearly shows that for high-frequency trading, investors rely on previous price movements in making future investment decisions. We provide clear evidence that market and limit orders flows are much more predictable if those orders are submitted to close an existing position than if they are used to open one. We interpret this finding as evidence for the existence of a monitoring effect, which has implications for theoretical market microstructure models and behavioral finance phenomena, such as the endowment effect.     

Price limit performance: New evidence from a quasi-natural experiment in China's ChiNext market

This study examines the impact of daily price limits on market performance and trading activity by using a quasi-natural experiment in China. It focuses on the case of the ChiNext market, where the daily price limits of stocks increased from 10% to 20% in 2020. The results show that, initially, the stock prices and occurrences of 10% price limit hits increase, but then decline after the new price limits have been implemented. The level of trading liquidity and volatility increases significantly, with a greater impact on the short term than the long term. These price limit performances are more pronounced for stocks with additional retail interest. The analysis of detailed trading data reveals that institutional investors initially purchase ChiNext stocks in large quantities, followed by retail investors who purchase smaller quantities. In the long run, institutional investors tend to increase their holdings, while retail investors tend to sell their holdings. Additionally, there is a temporary increase in investor attention, price synchronicity, and stock risks, followed by a decline. The findings suggest that wider price limits increase trading volumes and enhance long-term market efficiency, but encourage immediate price manipulation, causing short-term overreactions and long-term reversals. This study provides valuable insights for building an effective price limit system.     

Price limits in futures markets: effects on the price discovery process and volatility

Price limits are actively employed by many futures exchanges as a regulatory mechanism directed at reducing volatility and improving price discovery process. The aim of this paper is to investigate whether price limits achieve these goals without affecting market liquidity for a number of agricultural futures contracts. We employ models of changing volatility in order to show that price limits do not appear to significantly reduce market volatility. In addition, we find evidence confirming the hypothesis that price limits delay price discovery instead of facilitating it. Our results also suggest that the impact of price limits on volatility and price reversals, found in previous studies, are mainly due to the properties inherent to the futures returns, such as volatility clustering. Finally, although trading decreases significantly due to the price limits, traders do not seem to switch from the contracts affected by price limits to other maturities in order to minimize the impact of circuit breakers.     

Why Do Price Limits Exist in Stock Markets? A Manipulation‐Based Explanation

Numerous stock market regulators around the world impose daily price limits on individual stock price movements. We derive a simple model that shows that price limits may deter stock market manipulators. Based on our model's implications, we predict that regulators impose price limit rules for markets where the likelihood of manipulation is high. We present empirical evidence consistent with this hypothesis. Our study is the first to formally propose a manipulation‐based rationale for the existence of price limits in stock markets.     

交易限制与股票市场定价效率——基于创业板涨跌幅限制放宽的准自然实验研究

本文基于2020年8月24日创业板涨跌幅限制由10%扩大到20%这一政策变化建立准自然实验,从市场层面与公司事件层面探讨交易限制放宽的外生冲击下市场定价效率的变化。研究发现,涨跌幅限制放宽政策实施后,股票价格能更灵敏地反映公开市场信息,更多地包含公司层面特质信息,整体市场定价效率显著提升。进一步研究表明,涨跌幅限制放宽有效缓解了交易干扰问题,避免了过度交易行为延后,缓解了波动性外溢与价格发现延迟。异质性分析表明,无论是市场层面定价效率改善,还是事件层面波动性外溢、价格发现推迟与交易干扰问题的缓解,均在低信息透明度公司中更为显著。本文研究发现为验证涨跌幅限制会抑制股票市场定价效率的理论提供了直接经验证据,同时为推广完善市场化交易制度提供了有益启示。     

Are magnet effects caused by uninformed traders? Evidence from Taiwan Stock Exchange

Using transactions and quotes data, we find significant magnet effects of price limit rules in Taiwan Stock Exchange (TSEC). Consistent with Subrahmanyam [Subrahmanyam, A., 1994. Circuit breakers and market volatility: a theoretical perspective. Journal of Finance 49, 237–254], we find that when limit hits are imminent, trading activities intensify with higher volume and volatility. More importantly, our transactions data allows us to examine the roles of institutions and individuals in the magnet effects in TSEC. There is strong evidence that magnet effects are caused by uninformed individuals, whereas if trade volumes are dominated by institutions, no significant magnet effect is found. The policy implication of our findings is that transparency and institutional participation can help to reduce the frequency of magnet effects.     

SWITCHING TO A TEMPORARY CALL AUCTION IN TIMES OF HIGH UNCERTAINTY

We evaluate a stock-specific circuit breaker implemented in several European stock exchanges, which consists of a short-lived call auction triggered by intraday stock-specific price limits. It differs from U.S. trading halts in that it is short-lived and nondiscretionary, and a trading mechanism (continuous or discrete) is always going. It differs from daily price limits in that trade prices are not restricted once the limit is hit. Intraday price ranges are smaller and adjusted to the recent volatility, so that limit hits are more frequent. We contribute to the debate about circuit breakers by enlarging the span of these mechanisms studied.     

The Effectiveness of Price Limits and Stock Characteristics: Evidence from the Shanghai and Shenzhen Stock Exchanges

We examine the effectiveness of price limits on Chinese A shares and investigate the characteristics of those stocks that hit their price limits more frequently. We find that the effect of price limits is asymmetric for the A shares in upward and downward price movements and different for bullish and bearish sample periods. During a bullish period price limits effectively reduce stock volatility for downward price movements, but not for upward price movements; while during a bearish period price limits effectively reduce stock volatility for upward price movements, but not for downward price movements. Second, price limits delay efficient price discovery for upward price movements, but not for downward price movements. However, we do not find evidence to suggest that price limits harmfully interfere with the stock trading processes in the Chinese A share markets. Finally, we find that actively traded stocks hit their price limits more often and tend to hit the lower limit more frequently when overall market conditions are bearish. Stocks with high book-to-market values of equity hit their upper price limits more frequently, while stocks with a high ratio of tradable shares tend to hit their price limits less frequently.JEL Classification: G10, G14, G15     

A comparison of trading and non-trading mechanisms for price discovery

This paper compares trading and non-trading mechanisms for price discovery during the Nasdaq pre-open and examines whether prices discovered though non-trading mechanisms are less efficient or reveal less information than prices discovered through trading. As Nasdaq pre-open trading volume increased, the opening price became more efficient and price discovery shifted from the opening trade to the pre-open. Price discovery shifted from the trading day to the pre-open only for the highest-volume stocks. These results suggest that pre-open trading contributes to the efficiency of the opening price, but that a critical threshold of trading volume is required to increase the amount of information in the opening price.     

Measurement matters: Productivity-adjusted weighted average relative price indices

Commonly used trade-weighted real exchange rate indices are computed as indices-of-indices, and thus do not adequately account for growth in trade with developing countries. Weighted Average Relative Price (WARP) indices solve this problem but do not control for productivity differences, as developing countries are observed to have lower price levels via the Penn Effect. I remedy these problems in two ways. First I propose a Penn Effect productivity adjustment to Weighted Average Relative Price indices (P-WARP). Secondly, I introduce a Weighted Average Relative Unit Labor Cost index (WARULC) for manufacturing and show that this measure does a much better job predicting trade imbalances and declines in manufacturing employment than the IMF's Relative ULC measure created as an index-of-indices. The new series reveal that for many countries currently mired in liquidity traps, relative prices reached historic highs heading into the financial crisis of 2008. I document that in 2002 – during the surprisingly sudden collapse in US manufacturing – US relative prices had not been that overvalued relative to trading partners since the worst year of the Great Depression.