Stock and option market divergence in the presence of noisy information

We examine market behavior of the stock and option markets upon the arrival of noisy information in the form of CNBC’s Mad Money recommendations. If stock and option markets are not equally efficient, they should respond differently to noisy information, with the less efficient market more susceptible to noise. We find that the stock market is less efficient than the option market. The abnormal difference between option-implied and actual stock returns is negative and significant upon exposure to noisy information. This difference may yield an economically significant monthly trading profit of up to 5%. We conclude that the stock market is more susceptible to noisy information than the option market and is therefore less efficient.     

股票流动性与中国企业创新策略:流水不腐还是洪水猛兽？

中国情境下股票流动性对企业创新的影响是激励机制还是压力机制占主导地位？本文基于上市公司分类专利的申请、授权、终止数据研究发现:一方面,股票流动性使企业发明专利申请显著增加,但能通过实质审查的授权增长极少,说明申请质量明显下滑;另一方面,股票流动性使创新含量较低的实用新型与外观设计授权显著增加,且这些专利拖累了企业盈利表现,法律效力提前终止的数量也明显更多,揭示企业实际上是以“策略性创新”来应对资本市场压力,加剧了“专利泡沫”问题。分样本检验发现,“重数量轻质量”的创新策略集中体现于民营、传统行业及长期机构投资者持股较少的企业。稳健性检验替换关键指标构造和模型估计方法、构造工具变量克服潜在内生性问题,前述结论仍然成立。本文启示,金融制度设计应防范资本市场压力对企业创新的“意外伤害”,更好地实现“以金融助实体、以改革促发展”的目标。     

Are scientific indicators of patent quality useful to investors?

Together with the number of patents and the value of R&D expenditures, scientific measures of patent quality give investors a useful basis upon which to judge the economic merit of the firm's inventive and innovative activity. Especially in the case of small cap and relatively low P/E high tech companies, we find a favorable stock-price influence when both the number of patents, the scientific merit of those patents, and R&D spending is high. Patent quality information also appears germane in the case of large cap high-tech companies with relatively high P/E ratios. In short, patent citation information may indeed help investors judge the future profit-earning potential of a firm's scientific discoveries.     

Is there price discovery in equity options?

We use tick-by-tick quote data for 39 liquid US stocks and options on them, and we focus on events when the two markets disagree about the stock price in the sense that the option-implied stock price obtained from the put-call parity relation is inconsistent with the actual stock price. Option market quotes adjust to eliminate the disagreement, while the stock market quotes behave normally, as if there were no disagreement. The disagreement events are typically precipitated by stock price movements and display signed option volume in the direction that tends to eliminate the disagreements. These results show that option price quotes do not contain economically significant information about future stock prices beyond what is already reflected in current stock prices, i.e., no economically significant price discovery occurs in the option market. We also find no option market price discovery using a much larger sample of disagreement events based on a weaker definition of a disagreement, which verifies that the findings for the primary sample are not due to unusual or unrepresentative market behavior during the put-call parity violations.     

Do insiders trade on innovation?

We find that pure insider share purchases—which we define as insider purchases over two successive years without any corresponding sales—are a strong predictor of a firm’s patent applications. The predictability increases with the quality of the patent: Applications for the highest-quality, breakthrough patents increase by 21% in the year following pure insider purchases in our sample. These purchases are associated with large abnormal stock returns of 1.1% per month (14% annualized) over the subsequent three-year period. We also document that stock price responds less to the subsequent announcement of the grant of patent if the application for the patent has been preceded by pure insider purchases, consistent with the idea that insider purchases reveal information about future firm innovation. Our evidence has implications for understanding insider trading within technology companies that have become a dominant feature of US stock markets in recent decades.     

The option to stock volume ratio and future returns

We examine the information content of option and equity volumes when trade direction is unobserved. In a multimarket asymmetric information model, equity short-sale costs result in a negative relation between relative option volume and future firm value. In our empirical tests, firms in the lowest decile of the option to stock volume ratio (O/S) outperform the highest decile by 0.34% per week (19.3% annualized). Our model and empirics both indicate that O/S is a stronger signal when short-sale costs are high or option leverage is low. O/S also predicts future firm-specific earnings news, consistent with O/S reflecting private information.     

Reverse innovation and firm value in emerging markets: Evidence from China

Reverse innovation (RI) patents, which apply to intellectual property that is created in an emerging country but patented in a developed country, are better representatives of innovation value than domestic patents in emerging economies. We argue that RI patents contribute to firm value by proxying for the private value of innovation, generating product market value, and signalling firms’ capabilities. Using a sample of Chinese-listed companies, we find RI patents positively relate to firms’ short- and long-term market value. This effect is stronger for firms with high innovative intensity and managerial ability. We also explore the mechanisms behind the relationship between RI and firm value. We demonstrate that, in addition to the domestic patent functions of creating value and capturing innovation rent, RI patents can further leverage firm value by signalling firm quality to customers and investors in developed markets, a function that is unique to RI patents.     

专利提前公开的资本市场动因——基于企业被并购压力视角的研究

随着我国资本市场建设的日益完善,上市公司控制权市场活跃度得到显著提升,企业如何应对被并购压力成为值得关注的议题。本文研究企业是否会选择发明专利公开时点来应对被并购压力。研究发现,当被并购压力增大时,上市公司会越早公开专利。这是因为专利提前公开能够提升公司股票的异常回报,从而降低企业成为被并购目标的可能性或提高企业可获得的并购溢价。异质性分析发现:(1)被并购压力增大时,既有分析师关注度和风险投资者持股比例越高的企业越可能提前公开专利;(2)企业更可能选择技术成熟、质量较高的专利进行公开;(3)其他替代策略的存在会削弱被并购压力对专利提前公开的影响。在使用工具变量、行业并购政策变化和举牌事件作为外生冲击对内生性问题进行处理后,结果仍然稳健。     

Information Content of Business Methods Patents

We examine the market reaction to business method patents granted to publicly traded firms. Our findings suggest that the State Street decision represents a turning point not only for the growth in the number of business method patent filings, but also in the market's awareness and perception of value creation for the filing firms. The granting of a business method patent evokes a positive average stock price reaction, especially in the post‐State Street period. Cross‐sectional differences in abnormal returns depend on the type of patent granted. The market reaction also differs based on industry classification.     

Internal information quality and patent-related innovation

This study investigates how the quality of information available within a firm affects patent-related innovative activities. Relying on recent theoretical and empirical research, we use externally observable information attributes to proxy for the quality of internal information. Our empirical results indicate that firms with higher internal information quality generate more patents and patent citations. Cross-sectional analyses show that this positive effect is greater when firms are susceptible to greater internal information frictions due to firm decentralization, short management team tenure, and long product development cycles. We also document that firms experience an increase in patents and patent citations following an improvement of internal information quality proxied by internal control weakness remediation. Overall, our results suggest that the positive relation between internal information quality and task performance extends to patent-related innovation, a non-routine type of task that may rely on information originating from sources other than firms’ formal internal information systems.     

Risk-adjusted option-implied moments

This paper provides a new way of converting risk-neutral moments into the corresponding physical moments, which are required for many applications. The main theoretical result is a new analytical representation of the expected payoffs of put and call options under the physical measure in terms of current option prices and a representative investor’s preferences. This representation is then used to derive analytical expressions for a variety of ex-ante physical return moments, showing explicitly how moment premiums depend on current option prices and preferences. As an empirical application of our theoretical results, we provide option-implied estimates of the representative stock market investor’s disappointment aversion using S&P 500 index option prices. We find that disappointment aversion has a procyclical pattern. It is high in times of high index levels and declines when the index falls. We confirm the view that investors with high risk aversion and disappointment aversion leave the stock market during times of turbulence and reenter it after a period of high returns.     

Implied volatility skews and stock return skewness and kurtosis implied by stock option prices

The Black-Scholes* option pricing model is commonly applied to value a wide range of option contracts. However, the model often inconsistently prices deep in-the-money and deep out-of-the-money options. Options professionals refer to this well-known phenomenon as a volatility ‘skew’ or ‘smile’. In this paper, we examine an extension of the Black-Scholes model developed by Corrado and Su that suggests skewness and kurtosis in the option-implied distributions of stock returns as the source of volatility skews. Adapting their methodology, we estimate option-implied coefficients of skewness and kurtosis for four actively traded stock options. We find significantly nonnormal skewness and kurtosis in the option-implied distributions of stock returns.     

The information content of option ratios

A broad stream of research shows that information flows into underlying stock prices through the options market. For instance, prior research shows that both the Put–Call Ratio (P/C) and the Option-to-Stock Volume Ratio (O/S) predict negative future stock returns. In this paper, we compare the level of information contained in these two commonly used option volume ratios. First, we find that P/C ratios contain more predictability about future stock returns at the daily level than O/S ratios. Second, in contrast to our first set of results, O/S ratios contain more predictability about future returns at the weekly and monthly levels than P/C ratios. In fact, our tests show that while P/C ratios contain predictability about future daily returns and, to some extent, future weekly returns, the return predictability in P/C ratios is fleeting. O/S ratios, on the other hand, significantly predict negative returns at all levels: daily, weekly, and monthly. While Pan and Poteshman (2006) show that signed P/C ratios, which require proprietary data, have predictive power, we find that unsigned P/C ratios, which do not require proprietary data, also have predictive power.     

IPO anomalies and innovation capital

Innovation capital are typically expensed and/or unrecognized as assets under current generally accepted accounting principles. This results in accounting-related information asymmetry. This paper examines the association of innovation capital (as measured here by the proxies of R&D expenditures and granted patents) and initial public offerings (IPO) anomalies. These anomalies include initial IPO underpricing, duration of honeymoon (a distinct feature of the Taiwanese IPO environment), and long-term performance. The theoretical model underlying this research is a signaling model. The results indicate that more innovative firms are more likely to be underpriced, and have longer honeymoon periods than less innovative firms. Further, the more innovative firms have positive and growing long-term market-adjusted returns. This stands in contrast to the declining long-term stock performance of initial public offering firms that is evidenced in the literature. We conclude that pre-IPO research and development expenditures disclosed in the IPO prospectus, official monthly reports of newly developed patents released to the public, and the frequency of patent citations significantly signal both underpricing and future market performance of IPO firms in Taiwan.     

市场操纵降低了中国股票市场的信息效率吗——来自沪市A股高频交易数据的经验证据

本文以尾市交易操纵为研究对象,尝试对中国股票市场可疑的尾市操纵行为进行识别与监测,并基于监测结果实证分析市场操纵如何影响市场信息效率。具体来看,本文利用沪市A股2013-2018年的日内高频交易数据,基于股票尾市交易相关指标异常变化特征,构建了尾市交易操纵识别模型,实证检验了市场操纵对信息效率的影响。研究结果表明,市场操纵对信息效率存在不利影响,市场操纵后股票流动性和股票波动性的异常变化是影响信息效率的关键传导路径,上述结论在考虑内生性问题后依然稳健。此外,研究还发现,国有企业、上市公司信息披露质量较高的情形下,市场操纵对信息效率不利影响程度较小。     

Giving Content to Investor Sentiment: The Role of Media in the Stock Market

I quantitatively measure the interactions between the media and the stock market using daily content from a popular Wall Street Journal column. I find that high media pessimism predicts downward pressure on market prices followed by a reversion to fundamentals, and unusually high or low pessimism predicts high market trading volume. These and similar results are consistent with theoretical models of noise and liquidity traders, and are inconsistent with theories of media content as a proxy for new information about fundamental asset values, as a proxy for market volatility, or as a sideshow with no relationship to asset markets.     

南橘北枳:A股市场的经济关联与股票回报

本文系统检验并比较了中国A股市场中行业动量、区域动量、供应链动量以及科技关联动量等经济关联动量的显著性及预测周期。本文发现,中国股票市场中经济关联因子呈现出与美国股票市场不同的规律,在月度层面行业动量显著,而科技关联因子只在周度上具有显著的预测能力。进一步分析科技关联动量发现,中国股票市场中科技关联因子能预测目标公司未来1-3周的股票收益和未来基本面的变化,据此构建的多空策略能够产生周度0.16%的超额收益(年化8.67%);机制检验发现,科技关联因子预测期短的原因是由于中国股票市场中存在较多具有博彩倾向的散户投资者;有限注意和市场摩擦两个机制检验证明科技关联动量源自错误定价。进一步检验发现,科技关联动量在国有企业和创新政策颁布后更加显著。本文补充了现有A股市场的动量研究,有助于理解中国股票市场规律、提升资本市场有效性。     

The current account and stock returns

In this paper, I use stock return data to test an intertemporal model of the current account. I find that the model performs well in three countries: the U.K., Canada, and Japan. Hall [Hall, R.E., 1978. Stochastic implication of the life cycle-permanent income hypothesis: theory and evidence. J. Polit. Econ. 86 (6), 971–987] points out that because stock price predicts the future state of the economy, it predicts consumption. Assuming that consumption depends on permanent income, my empirical finding indicates that a representative agent smoothes consumption based on stock market information. In other words, stock market returns yield information about permanent income.     

Innovation and Price Informativeness

We study whether the innovation decisions of a firm are improved as a result of information reflected in the firm's stock price. We show that firms with more informative stock prices, as measured by price nonsynchronicity, have better innovation outcomes, as measured by the number of patents and patent citations. Our results are not driven by managerial private information and are robust to various alternative specifications. We also find that price informativeness is more important to innovation when managers are less experienced or face greater uncertainty about the optimal innovation strategy, and that these effects are primarily observed in small‐ and mid‐sized firms where additional information may be of greater value. Our results are consistent with the notion that capital markets can have real effects on the economy.     

Why Are U.S. Stocks More Volatile?

U.S. stocks are more volatile than stocks of similar foreign firms. A firm's stock return volatility can be higher for reasons that contribute positively (good volatility) or negatively (bad volatility) to shareholder wealth and economic growth. We find that the volatility of U.S. firms is higher mostly because of good volatility. Specifically, stock volatility is higher in the United States because it increases with investor protection, stock market development, new patents, and firm‐level investment in R&D. Each of these factors is related to better growth opportunities for firms and better ability to take advantage of these opportunities.