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What Should We Expect When Testing for Price Response to News in Securities Litigation? — No. 1:21-md-02989 (S.D. Fla., Dkt. 582-7, entered 06/21/2023)

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Document 582-7 in Case 1:21-md-02989-CMA, entered on the FLSD docket 06/21/2023, is a 17-page August 2016 paper, What Should We Expect When Testing for Price Response to News in Securities Litigation?, by Dr. David I. Tabak, Senior Vice President of NERA Economic Consulting. The paper treats price response to news as a key consideration in testing market efficiency under Basic Inc. v. Levinson and Cammer v. Bloom, and explains why the Proof-by-Example approach, which presents a handful of news days followed by stock-price movements, was rebutted in In re PolyMedica Corp. Securities Litigation, 453 F. Supp. 2d 260 (D. Mass. 2006). Later pages discuss the comparison test endorsed by courts, which compares the percentage of days with news that have a statistically significant price movement with the percentage of days without news that have one.

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“What Should We Expect When Testing for Price Response to News in Securities Litigation? — No. 1:21-md-02989 (S.D. Fla., Dkt. 582-7, entered 06/21/2023).” Archived at Pandemic Darlings, https://pandemicdarlings.com/source-documents/gov-uscourts-flsd-590042-582-7-77920033e1/, SHA-256 dfb542ba496f9151d4e700718c891f9a89227aec8adc63701cc78d8c02944810.

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Case 1:21-md-02989-CMA Document 582-7 Entered on FLSD Docket 06/21/2023 Page 1 of 17




 August 2016




 What Should We Expect When Testing for
 Price Response to News in Securities Litigation?




 By Dr. David I. Tabak*       Introduction

                              The frequency with which a stock price is expected to respond to news is an important issue
                              in securities litigation. As one example, price response to news is an important factor in the
                              consideration of market efficiency. If a stock trades in an efficient market, there is generally
                              a presumption, under Basic Inc. v. Levinson, 485 U.S. 224, 108 S. Ct. 978, 99 L. Ed. 2d 194
                              (1988), that investors can rely on the market price of the stock to reflect the effects of any
                              material misrepresentation or omission.

                              Among the various tests employed to assess market efficiency, whether a stock, or other
                              security, responds to news has emerged as the key consideration. In part, this relates back to
                              the seminal Cammer v. Bloom case that set forth five factors that many courts have adopted
                              as part of their consideration of market efficiency. The Cammer Court noted, “Finally, it would
                              be helpful to a plaintiff seeking to allege an efficient market to allege empirical facts showing a
                              cause and effect relationship between unexpected corporate events or financial releases and an
                              immediate response in the stock price. This, after all, is the essence of an efficient market and
                              the foundation for the fraud on the market theory.”1




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                      The Proof-By-Example Approach

                      Following Cammer, there has been an evolving history of how experts and lawyers presented
                      empirical facts that might have been deemed to show a cause-and-effect relationship between
                      news and stock-price movements. An initially popular approach might be termed “Proof by
                      Example.” In this method, an expert or counsel for plaintiffs would present a handful of days
                      with news followed by a stock-price movement.2 A serious, and in fact, fatal, problem with
                      this approach is that one would expect to see such results if stock-price movements were
                      completely random and had no average correlation with news events. One can, for example,
                      look at a calendar and provide examples to “demonstrate” that Mondays are correlated with
                      even-numbered days of the month, or that Mondays are correlated with odd-numbered days
                      of the month. Similarly, in most securities-litigation cases, there are likely to be days with news
                      (“news days”) associated with large stock-price movements and news days associated with
                      typical or even small stock-price movements. Similarly, we would expect to see days without
                      news (“non-news days”) associated with both large and small stock-price movements.

                      The Proof-by-Example approach was forcefully rebutted in In re PolyMedica Corp. Securities
                      Litigation, 453 F. Supp. 2d 260 (D. Mass. 2006). In this case, the expert for plaintiffs
                      presented five days where there was news and what he claimed was an associated stock-
                      price response. The expert for defendants countered with an explanation of the reasoning
                      described above. The court agreed with the defense expert, and found that the plaintiffs’
                      expert’s “mere listing of five days on which news was released and which exhibited large
                      price fluctuations proves nothing.”3



                      The FDT Test and Its Successes

                      The failures of the Proof-by-Example approach, at least by practitioners and courts that
                      recognize those failures, raise the question of what a proper alternative should be. In 2004,
                      a law review article (co-authored by the author of this paper) and a submission by an expert
                      for defendants in a securities litigation advocated very similar, if not functionally identical,
                      approaches. “The ‘Less Than’ Efficient Capital Markets Hypothesis: Requiring More Proof from
                      Plaintiffs in Fraud-on-the-Market Cases” proposed a test that has since been referred to as
                      the “FDT Test.”4 The FDT Test can be conceptualized similarly to a medical study in which a
                      researcher wishes to determine if a drug is effective. To do so, the medical researcher runs
                      a study with two groups. One group, the control group, is either given no drug or is given a
                      placebo, while the other group, the treatment group, is given the drug in question. Results
                      between the two groups are then examined to see if they are different. In the FDT Test, stock-
                      price movements on news days (the treatment group) are compared to stock-price movements
                      on non-news days (the control group) to see if they are different. In particular, the FDT Test runs
                      an event study for each day in the period being examined and then uses the results of those
                      event studies to compare the fraction of news days with a statistically significant stock-price
                      movement to the fraction of non-news days with a statistically significant stock-price movement
                      to see if there is a difference between the two fractions. It further asks whether the difference
                      between the two fractions is itself statistically significant and is higher on news days.5




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                      The 2004 case alluded to above is Lehocky v. Tidel Tech., Inc., 220 F.R.D. 491 (S.D. Tex. 2004).
                      In this matter, the court found as follows (emphasis added):

                               Plaintiffs’ expert[] conducted an event study using Tidel’s trading data. He
                               identified two-day periods in which information pertaining to Tidel was
                               released to the public and separated those two day[] [periods] from other
                               two day periods in which there was no public information pertaining to Tidel.
                               The periods were classified into “information” versus “non-information days”
                               …. [Plaintiffs’ expert] concluded that the price changes on information
                               days versus non-information days was statistically significant, meaning
                               there was a related cause and effect relationship between [a] the
                               release of information pertaining to Tidel and [b] Tidel’s stock price.
                               Simply put, [Plaintiffs’ expert’s] tests indicated that Tidel’s stock price
                               reacted within a two day window to news releases concerning Tidel,
                               which indicates market efficiency.

                      While the terminology is slightly different, and the focus of plaintiffs’ expert in Tidel appears
                      to be on price changes, perhaps indicating the magnitude of changes and not merely
                      whether there was a change, the basic concept of employing a statistical comparison of
                      price movements on news days to those on non-news days is similar to the concept behind
                      the FDT Test.

                      More recently, courts have accepted a number of tests of market efficiency that directly follow
                      the FDT Test procedures, if not citing the FDT paper directly. See the following examples (with
                      all emphases added):

                      •   Lumen v. Anderson, No. 08-0514-CV-W-HFS (W.D. Mo. Feb. 10, 2012).

                               The expert also concluded FCStone’s stock was approximately one-and-
                               a-half to two times as likely to experience a change in stock price on
                               days when company-specific news was announced than on days when
                               it was not. However, for legal purposes, the critical question is whether the
                               price quickly absorbs and reflects news about the company because this
                               is what allows the legal presumption that (1) the price incorporates public
                               information and (2) the investor relied on the price as the repository of that
                               public information. [The defendants’ expert’s] report establishes that
                               when news about the company is made public, the company’s stock
                               price immediately incorporates the information. This is the essence of an
                               efficient market — perhaps not for an economist’s purposes, but for purposes
                               of Basic.

                      •   Smilovits v. First Solar, Inc., No. CV12-00555-PHX-DGC (D. Ariz. Oct. 8, 2013).

                               Plaintiffs submit that, overall, statistically significant price moves
                               occurred three times more often on days with relevant news than on
                               days without news.




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                      Furthermore, the court rejected defendants’ expert’s conclusion based on a discussion of days
                      when the stock apparently had no significant price change following news because, citing
                      Lumen, “there is no comparison to the number of times there were significant price changes
                      following important news.”

                      •   McIntire v. China MediaExpress Holdings, Inc., 38 F. Supp. 2d 415 (S.D.N.Y. 2014).

                               For that reason, courts have instead endorsed the comparison test that
                               [Plaintiffs’ expert] used. See, e.g., In re Alstom SA Sec. Litig., 253 F.R.D. 266,
                               280 (S.D.N.Y.2008). This test “involves comparing the percentage of days with
                               news that have a statistically significant price movement to the percentage of
                               days without news that have a statistically significant price movement.” Paul A.
                               Ferrillo et al., The “Less Than” Efficient Capital Markets Hypothesis: Requiring
                               More Proof from Plaintiffs in Fraud-on-the-Market Cases, 78 St. John’s L. Rev.
                               81, 120 (2004). If the stock price is significantly more likely to change on News
                               Days than on Non-News Days, that suggests a causal relationship between
                               material news and the stock price. Id.

                      •   In re Petrobras Securities Litigation, No. 14-cv-9662 (JSR) (S.D.N.Y. Feb. 2, 2016).

                               Both sides refer to [plaintiffs’ expert’s] methodology as an “FDT” test
                               because use of z-test to evaluate market efficiency was first proposed in a
                               law review article by three well-known securities econometric experts, whose
                               combined initials were “FDT.” See Paul A. Ferrillo, Frederick C. Dunbar, and
                               David Tabak, The “Less Than” Efficient Capital Markets Hypothesis: Requiring
                               More Proof from Plaintiffs in Fraud-on-the-Market Cases, 78 St. John’s L. Rev.
                               81, 119-22 (2004). [Defendants’ expert] contends that, because the article
                               was not peer-reviewed, a z-test cannot be used to show market efficiency.
                               Were [plaintiffs’ expert] using a novel or questionable statistical technique,
                               the Court would place more weight on the absence of peer review. But it is
                               not necessary for every application of a commonly used statistical technique
                               to be peer-reviewed. Indeed, the elegance of statistical methods is that they
                               can be applied to data sets of varying substantive significance, from rates
                               of emphysema to transactions on modern securities markets. Because the
                               Court is convinced that the z-test is a well-established and sound statistical
                               technique, the lack of peer review does not seriously undermine [plaintiffs’
                               expert’s] application of the z-test.




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                      Challenges to the FDT Test

                      Not all cases in which a test to examine the fractions of news and non-news days associated
                      with statistically significant returns was employed by plaintiffs have resulted in a finding of
                      market efficiency. Defendants do have at least two wins with the argument that all or nearly all
                      news dates should be associated with statistically significant returns:

                      •   In re Federal Home Loan Mortgage Corp., No. 09 Civ. 832 (MGC) (S.D.N.Y. Mar. 27, 2012).6

                               A plaintiff must show that the market price responds to most new, material
                               news.
                               …
                               At his first deposition, [plaintiffs’ expert] testified that if new information
                               had been released into the market on each of his initial 28 event days, one
                               could expect to see statistically significant abnormal returns on each of the 28
                               days in an efficient market. In contrast, [defendants’ expert] testified that an
                               economist may conclude that a market is efficient if it reacts to news 80 to
                               90% of the time, depending on the number of news dates at issue.

                      •   George v. China Automotive Systems, Inc., No. 11 Civ. 7533 (KBF) (S.D.N.Y. July 3, 2013).

                               Even assuming that the methodology was proper, showing that only seven
                               out of sixteen days resulted in a market reaction is an insufficient foundation
                               upon which to pronounce market efficiency. (Id. at 100.) (To state the obvious,
                               seven out of sixteen is less than 50%.)

                      In fact, defendants have frequently argued that some large number of dates with news should
                      be associated with statistically significant stock-price movements.7 Yet, it is not clear if there
                      is any case in which defendants have cited some empirical or even sound theoretical basis
                      for an argument that there should be some minimum fraction of news days associated with
                      statistically significant returns.



                      How Often Should Stocks Respond to News in a Statistically
                      Significant Manner?

                      Theoretical Issues
                      An easy, though informal, proof of why there is no theoretical basis for an argument that a
                      specific share of news days should be associated with a statistically significant price movement
                      can be made by pointing out that statistical significance is determined at various levels, with
                      the 5% significance level being the most common in financial economics.8 Assume that under
                      the 5% significance level, some fraction of news days is associated with statistically significant
                      price movements when the series of event studies that form the FDT Test is undertaken. Under
                      another significance level, say the stricter 1% significance level, a different, and smaller, fraction
                      would be associated with statistically significant price movements. In fact, a different fraction
                      would exist for each level of statistical significance (though with a discrete count of days, there
                      could be cases where the fraction would remain constant over ranges of levels of statistical
                      significance until the significance level is increased (reduced) to the point where another day



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                      fails (succeeds) in becoming statistically significant). Thus, there cannot be some constant
                      expected fraction of news days that should be associated with statistically significant price
                      movements in an efficient market, not even 50%, as that fraction would depend on the level of
                      statistical significance being employed.

                      One can also formally show that the expected fraction of news days that should be associated
                      with statistically significant stock-price movements will depend on (1) the distribution of market-
                      adjusted stock-price movements on news days and (2) the cutoff for determining what size
                      market-adjusted stock-price movement is deemed statistically significant. It is notable that under
                      the standard academic practice of not filtering news days from the period used to estimate the
                      “market model” that provides the parameters for determining whether days are associated with
                      statistically significant stock-price movements, the share of all days that are news days will affect
                      that cutoff. Again, there is no reason for the fraction of news days that should be associated
                      with statistically significant stock-price movements to necessarily be above or below 50%.

                      Intuitively, one can see at least part of the reason why the fraction of news days associated
                      with statistically significant price movements is indeterminate theoretically by considering
                      that the definition of a news day can differ. So, if one defines a news day as any day with
                      an earnings announcement, we might expect a certain fraction of those news days to be
                      associated with a statistically significant stock-price movement. However, if we define a news
                      day to be one with an earnings surprise (i.e., an earnings announcement where the reported
                      earnings are different from the consensus estimate, often proxied for by the average of
                      earnings estimates provided by analysts), then we might expect the fraction of news days
                      associated with statistically significant returns to be greater. Alternatively, if we have a broader
                      definition of news, such as mentions of the company in any news story, we might expect the
                      fraction of those news days associated with a statistically significant stock-price movement to
                      be lower. There is no theoretical or mathematical/statistical reason to believe that the fraction
                      of news days associated with statistically significant returns should exceed 50% as a general
                      matter in an efficient market.

                      Academic Literature
                      Given the lack of a theoretical standard for the fraction of news days that should be associated
                      with statistically significant returns, we might ask if there is any guidance from the academic
                      literature on this subject. There is in fact a long literature on the general inability of news to
                      substantially explain stock-price movements. One seminal article is Richard Roll, “R2,” Journal
                      of Finance 43, (1988). The abstract for this paper begins, “Even with hindsight, the ability
                      to explain stock price changes is modest. R2s were calculated for the returns of large stocks
                      as explained by systematic economic influences, by the returns on other stocks in the same
                      industry, and by public firm-specific news events. The average adjusted R2 is only about .35 with
                      monthly data and .20 with daily data.”

                      Following Roll’s paper, the literature typically focused on how much stock prices move even
                      after accounting for news (e.g., if stock prices tended to move by 10% on news days and
                      8% on non-news days, one could say that news explained 20% of stock-price movements).
                      However, the typically more relevant question brought forth by plaintiffs and defendants in
                      securities litigations is how often news should elicit a stock-price movement, the measure
                      examined in the FDT Test. There are a few articles that do address this issue directly. One such




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                      paper is Jacob Boudoukh et al., Which News Moves Stock Prices? A Textual Analysis, Working
                      Paper No. 18725, National Bureau of Economic Research, October 14, 2013. The authors find
                      that “identified news days are 32.5% more likely to coincide with the bottom and top 10% of
                      return days.”9 That is, while one would expect 20% of news days to be in the bottom and top
                      10% of returns if price movements were unaffected by news, instead 26.5% (i.e., 20% plus an
                      additional 32.5% of that 20%) of news days are in that group. Recall that the 5% significance
                      level represents the bottom and top 2.5% of the sample. As 26.5% of news days are in the
                      bottom and top 10% of the sample, 26.5% is an upper bound of the percentage of news
                      days that could be in the bottom and top 2.5% of the sample and thus be associated with
                      statistically significant returns at the 5% level.

                      Next, we turn to John M. Griffin, Nicholas H. Hirschey, Patrick J. Kelly, “How Important Is the
                      Financial Media in Global Markets?” Review of Financial Studies, 2011. Chart A on page 3971
                      of the article shows that if one sorts days by the magnitude of their price movements, with 100
                      representing the largest movement in absolute magnitude and 0 the smallest, the mean rank
                      for news days in the U.S. is about 57 or 58.10 That is, rather than all or nearly all of the news
                      days falling in the upper 5% of the distribution (i.e., ranks 95-100), which by definition is the set
                      of statistically significant price movements at the 5% level, the price movement for a “typical”
                      news day is above the midpoint (i.e., a rank of 50) but is not statistically significant (i.e., in ranks
                      95-100). That is, only news that is well above average in importance to investors should be
                      expected to give rise to a statistically significant price movement.

                      Both of these papers show that the assumption that half of all news days should be associated
                      with statistically significant returns does not hold in practice, at least for the news, stocks, and
                      time periods covered by these articles.

                      New Empirical Analyses
                      We now turn to furthering those analyses. In particular, in this paper, we address the
                      question of what percent of “news days” is associated with a statistically significant stock-
                      price movement.

                      As a first analysis, we begin with a methodology designed to give a high estimate of the
                      number of events that will be associated with statistically significant returns when the event
                      studies underlying the FDT Test are performed. Our sample is all members of the S&P 500 Index
                      as of December 31, 2015, excluding those that began trading after April 2014. The examination
                      period covers 2010 through 2015 and a news day is defined as an earnings announcement.
                      For each stock, a market model is calculated over each calendar year from 2009 through 2014
                      using the S&P 500 Index as the explanatory variable, and the parameters and standard error of
                      each market model are used to determine the statistical significance of the stock’s daily price
                      movements during the following calendar year.

                      The events examined are the earnings announcements by each company in the time period
                      examined. To account for the possibility that an earnings announcement came out either
                      before or after the close of trading, and to increase the probability of finding a statistically
                      significant return associated with each earnings announcement, we characterize an earnings
                      announcement as being associated with a statistically significant return if either the day
                      of the earnings announcement or the following trading day has a statistically significant




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                                           return, or both.11 As a result, we would not expect merely 5% of news days to be associated
                                           with statistically significant returns merely by chance, but (if markets are efficient and price
                                           movements on consecutive days are independent), we would expect roughly twice that (in
                                           fact, 9.75%) of news days to be associated with a statistically significant price movement.12 The
                                           results are presented in column (1) of Table 1 below, which shows the number of companies in
                                           different percentages of statistically significant returns across its earnings announcements.


 Table 1. Excess Returns on Earnings Announcements1 for 504 Companies in the S&P 500 Index,
          as of December 31, 2015,2 over the Period January 4, 2010 through December 31, 2015

 		                                                                                Daily Returns Predicted Using the S&P 500 Index 3

                                                              All Earnings                Small Earnings             Medium Earnings               Large Earnings
                                                            Announcements 4              Announcements 4             Announcements 4              Announcements 4

                                                                     (1)                          (2)                         (3)                           (4)		

 Assuming that there is a significant return if the excess return on the announcement day or the following day is
 statistically significant at the 5% level:
 Total Number of Companies5,6                                      496                          487                          478                          448
 Average Number of Earnings                                        23.3                         10.8                         5.0                           8.6
 Announcements7

 Percent of companies with the percent of earnings announcements with statistically significant returns in the range:
 < = 20%                                                         2.0%                          8.2%                      15.5%                         12.9%		
 > 20% and < = 40%                                              19.2%                         18.5%                      21.8%                         18.3%
 > 40% and < = 60%                                              45.8%                         37.4%                      24.9%                         33.5%
 > 60% and < = 80%                                              30.8%                         25.5%                      21.8%                         19.6%
 > 80% and < = 100%                                              2.2%                         10.5%                      16.1%                         15.6%

 Percent of earnings announcements with statistically significant returns for the median company:		
                                                                54.2%                         53.8%                      50.0%                        50.0%

 Notes and Sources:												
 Price data and dividend data obtained from FactSet Research Systems, Inc.							
 Returns were adjusted for dividends and the effective trading date of the earnings dates were used. 					
 1 Earnings announcement dates obtained from FactSet Research Systems, Inc.
 2 S&P 500 Index constituents, as of December 31, 2015, obtained from Bloomberg, L.P.
 3 Company stock price returns for each calendar year are predicted by regressing the daily logarithmic returns of the company’s stock on the daily logarithmic returns
   of the S&P 500 Index over the previous calendar year. Stock price returns on January 4, 2016, are predicted by regressing the daily logarithmic returns of the
   company’s stock on the daily logarithmic returns of the S&P 500 Index, over the period: January 2, 2014, through December 31, 2014.
 4 Earnings announcements are classified as “Small,” “Medium,” or “Large” based on the absolute value of the I/B/E/S amount earnings-per-share (EPS)
   surprise reported divided by the company stock price on the report date. “Small” events have an absolute EPS surprise of less than or equal to 0.075% of the
   closing price on the report date, “Medium” events have an absolute EPS surprise greater than 0.075% of the closing price on the report date but less than or
   equal to 0.15% of the closing price on the report date, and “Large” events have an absolute EPS surprise greater than 0.15% of the closing price on the report
   date. EPS surprises are calculated from the mean I/B/E/S EPS estimate for that earnings report.
 5 The following companies were excluded from the analyses in columns (1) to (4) because their shares began trading publicly after April 2014: CSRA, Inc., Hewlett
   Packard Enterprise Co., Synchrony Financial, Alphabet, Inc. (class C shares), Navient Corp., PayPal Holdings, Inc., Columbia Pipeline Group, Inc., and Baxalta, Inc. In
   addition, News Corp. was excluded from the analyses in columns (2) to (4) because of an inability to locate I/B/E/S EPS surprise data for 2010-2015.
 6 Values in this row represent the total number of companies with at least one earnings day of the type indicated in columns (1) to (4).
 7 Calculated for only companies with at least one earnings day of the given type.




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                      A number of results are apparent from Table 1 and the data underlying that table. First,
                      it is rarely the case that all or nearly all of the earnings announcements are associated
                      with statistically significant returns. Even allowing for two opportunities to find a
                      statistically significant return (on either the day of or the trading day following the earnings
                      announcement, as discussed above) for each earnings announcement, only 2.2% of S&P 500
                      companies have more than 80% of their earnings announcements associated with statistically
                      significant returns.13

                      For the median S&P 500 company, 54.2% of its earnings announcements were associated
                      with statistically significant returns, again allowing for two opportunities to find a statistically
                      significant return. Thus, the argument that even a majority of news announcements should
                      be associated with statistically significant returns would not hold for approximately half of the
                      members of the S&P 500 under this set of parameters.

                      Next, we refine this analysis by dividing the earnings announcements, or surprise, into “Small,”
                      “Medium,” and “Large” categories by comparing the actual earnings figure to the consensus
                      estimate from I/B/E/S.14 If the earnings surprise divided by the stock’s closing price on the
                      earnings report date yields a figure of at most 0.075%, the earnings announcement is defined
                      to be Small; if the earnings surprise comes in more than 0.075%, but within 0.15%, of the
                      closing price on the report date, the earnings announcement is defined to be Medium; and
                      if earnings surprise come in more than 0.15% from the closing price on the report date, the
                      earnings announcement is defined to be Large.15 Columns (2) through (4) of Table 1 show
                      the percent of Small, Medium, and Large earnings announcements that are associated with
                      statistically significant returns.

                      As seen in Table 1, when we define news days to include only one of the categories of earnings
                      announcements, we still find fewer than 17% of S&P 500 companies have a proportion of
                      news days to be associated with statistically significant returns that exceeds 80%, with both the
                      Medium and Large categories coming in between 15% and 17%.16

                      In Table 2, we replicate Table 1 but add an industry index for each market model. In particular,
                      we add the SPDR Sector ETF corresponding to each company’s GICS Sector Code. As seen in
                      the table, the results do not change substantially from what we observe in Table 1, though
                      more earnings-announcement dates tend to be associated with statistically significant returns
                      (e.g., if we examine Medium and Large earnings surprises, 18.6% and 16.5% of companies for
                      the two categories, respectively, have at least 80% of the announcements dates associated with
                      a statistically significant return.)

                      For our last set of analyses of earnings announcements for S&P 500 companies, we examine
                      whether the price movements for the Small, Medium, and Large earnings announcements are
                      in the direction one would expect based solely on the direction of the earnings surprise.17 This
                      expands upon the results from the two academic papers discussed above, neither of which
                      imposes a directionality requirement on the returns. The results are shown in Table 3.




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 Table 2. Excess Returns on Earnings Announcements1 for 504 Companies in the S&P 500 Index,
          as of December 31, 2015,2 over the Period January 4, 2010 through December 31, 2015

 		Daily Returns Predicted Using the S&P 500 Index and SPDR Sector ETFs3

                                                              All Earnings                Small Earnings             Medium Earnings               Large Earnings
                                                            Announcements 4              Announcements 4             Announcements 4              Announcements 4

                                                                     (1)                          (2)                         (3)                           (4)		

 Assuming that there is a significant return if the excess return on the announcement day or the following day is
 statistically significant at the 5% level:
 Total Number of Companies5,6                                      496                          487                          478                          448
 Average Number of Earnings                                        23.3                         10.8                         5.0                           8.6
 Announcements7

 Percent of companies with the percent of earnings announcements with statistically significant returns in the range:
 < = 20%                                                         1.6%                           6.8%                     14.2%                         10.9%		
 > 20% and < = 40%                                              16.9%                         18.5%                      19.5%                         19.4%
 > 40% and < = 60%                                              46.4%                         36.8%                      24.3%                         29.7%
 > 60% and < = 80%                                              32.3%                          27.1%                     23.4%                         23.4%
 > 80% and < = 100%                                              2.8%                         10.9%                      18.6%                         16.5%

 Percent of earnings announcements with statistically significant returns for the median company:		
                                                                54.2%                         55.0%                      52.3%                         53.8%

 Notes and Sources:												
 Price data and dividend data obtained from FactSet Research Systems, Inc.							
 Returns were adjusted for dividends and the effective trading date of the earnings dates were used. 					
 1 Earnings announcement dates obtained from FactSet Research Systems, Inc.
 2 S&P 500 Index constituents, as of December 31, 2015, obtained from Bloomberg, L.P.
 3 Company stock price returns for each calendar year are predicted by regressing the daily logarithmic returns of the company’s stock on the daily logarithmic returns
   of the S&P 500 Index and the SPDR Sector ETF corresponding to the company’s GICS Sector Code, over the previous calendar year. Stock price returns on January
   4, 2016, are predicted by regressing the daily logarithmic returns of the company’s stock on the daily logarithmic returns of the S&P 500 Index and the SPDR Sector
   ETF corresponding to the company’s GICS Sector Code, over the period: January 2, 2014, through December 31, 2014. The SPDR Technology Sector ETF (ticker:
   “XLK”) was used for companies with the GICS codes 45 (Information Technology) and 50 (Telecommunication Services).
 4 Earnings announcements are classified as “Small,” “Medium,” or “Large” based on the absolute value of the I/B/E/S amount earnings-per-share (EPS) surprise
   reported divided by the company stock price on the report date. “Small” events have an absolute EPS surprise of less than or equal to 0.075% of the closing price
   on the report date, “Medium” events have an absolute EPS surprise greater than 0.075% of the closing price on the report date but less than or equal to 0.15% of
   the closing price on the report date, and “Large” events have an absolute EPS surprise greater than 0.15% of the closing price on the report date. EPS surprises are
   calculated from the mean I/B/E/S EPS estimate for that earnings report.
 5 The following companies were excluded from the analyses in columns (1) to (4) because their shares began trading publicly after April 2014: CSRA, Inc., Hewlett
   Packard Enterprise Co., Synchrony Financial, Alphabet, Inc. (class C shares), Navient Corp., PayPal Holdings, Inc., Columbia Pipeline Group, Inc., and Baxalta, Inc. In
   addition, News Corp. was excluded from the analyses in columns (2) to (4) because of an inability to locate I/B/E/S EPS surprise data for 2010-2015.
 6 Values in this row represent the total number of companies with at least one earnings day of the type indicated in columns (1) to (4).
 7 Calculated for only companies with at least one earnings day of the given type.




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 Table 3. Excess Returns on Earnings Announcements1 for 504 Companies in the S&P 500 Index,
          as of December 31, 2015,2 over the Period January 4, 2010 through December 31, 2015

 		Daily Returns Predicted Using the S&P 500 Index and SPDR Sector ETFs3

                                                              All Non-Zero                Small Non-Zero                Medium                        Large
                                                                Earnings                    Earnings                    Earnings                     Earnings
                                                            Announcements 4              Announcements 4             Announcements 4              Announcements 4

                                                                     (1)                          (2)                         (3)                           (4)		

 Assuming that there is a significant return if the excess return on the announcement day or the following day is statistically
 significant at the 5% level and is in the same direction as the earnings news:
 Total Number of Companies5,6                                      495                           487                         478                          448
 Average Number of Earnings                                        23.1                          10.7                        5.0                           8.6
 Announcements7

 Percent of companies with the percent of earnings announcements with statistically significant returns in the range:
 < = 20%                                                         9.1%                         30.2%                      27.6%                         19.4%		
 > 20% and < = 40%                                              48.9%                         40.0%                      32.0%                         30.4%
 > 40% and < = 60%                                              38.4%                         23.0%                      22.2%                         27.2%
 > 60% and < = 80%                                               3.4%                          3.9%                      11.1%                         11.8%
 > 80% and < = 100%                                              0.2%                          2.9%                       7.1%                         11.2%

 Percent of earnings announcements with statistically significant returns for the median company:		
                                                                 37.5%                        31.3%                      33.3%                         41.0%

 Notes and Sources:												
 Price data and dividend data obtained from FactSet Research Systems, Inc.							
 Returns were adjusted for dividends and the effective trading date of the earnings dates were used. 					
 1 Earnings announcement dates obtained from FactSet Research Systems, Inc.
 2 S&P 500 Index constituents, as of December 31, 2015, obtained from Bloomberg, L.P.			
 3 Company stock price returns for each calendar year are predicted by regressing the daily logarithmic returns of the company’s stock on the daily logarithmic returns
   of the S&P 500 Index and the SPDR Sector ETF corresponding to the company’s GICS Sector Code over the previous calendar year. Stock price returns on January 4,
   2016, are predicted by regressing the daily logarithmic returns of the company’s stock on the daily logarithmic returns of the S&P 500 Index and the SPDR Sector
   ETF corresponding to the company’s GICS Sector Code, over the period: January 2, 2014, through December 31, 2014. The SPDR Technology Sector ETF (ticker:
   “XLK”) was used for companies with the GICS codes 45 (Information Technology) and 50 (Telecommunication Services).
 4 Earnings announcements where the EPS reported was exactly the same as the mean EPS estimate are excluded. Earnings announcements are classified as “Small,”
   “Medium,” or “Large” based on the absolute value of the I/B/E/S amount earnings-per-share (EPS) surprise reported divided by the company stock price on the
   report date. “Small” events have an absolute EPS surprise of less than or equal to 0.075% of the closing price of the stock on the report date, “Medium” events have
   an absolute EPS surprise greater than 0.075% of the closing stock price on the report date but less than or equal to 0.15% of the company price on the report date,
   and “Large” events have an absolute EPS surprise greater than 0.15% of the closing price on the report date. EPS surprises are calculated from the mean I/B/E/S EPS
   estimate for that earnings report.
 5 The following companies were excluded from the analyses in columns (1) to (4) because their shares began trading publicly after April 2014: CSRA, Inc., Hewlett
   Packard Enterprise Co., Synchrony Financial, Alphabet, Inc. (class C shares), Navient Corp., PayPal Holdings, Inc., Columbia Pipeline Group, Inc., and Baxalta, Inc. In
   addition, News Corp. was excluded from the analyses in columns (2) to (4) because of an inability to locate I/B/E/S EPS surprise data for 2010-2015.
 6 Values in this row represent the total number of companies with at least one earnings day of the type indicated in columns (1) to (4).
 7 Calculated for only companies with at least one earnings day of the given type.




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                     The results are similar to those in Table 2, but with the additional restriction that to qualify
                     as a statistically significant result, the price movement has to be in the same direction of the
                     earnings surprise, reducing the number of announcements that are considered to be associated
                     with a statistically significant price movement. There are (at least) three theoretical reasons
                     for this. First, some of the difference may be due to noise, in which a day with, say, a positive
                     earnings announcement should engender a positive price movement, but due to a large
                     negative degree of noise, the price movement is actually negative and statistically significant.
                     However, this cannot reasonably be expected to explain the full difference in the tables. In
                     particular, since we are using the 5% significance level, we would expect to obtain a statistically
                     significant price movement in the “incorrect” direction either (1) if the movement is in the
                     “incorrect” direction on the first day but not in the “correct” direction on the second, or (2)
                     neither in the “correct” nor “incorrect” direction on the first day, but in the “incorrect” direction
                     on the second day. Consequently, there is a 4.8125% chance of finding a statistically significant
                     movement in the “incorrect” direction.18 Second, it could be the case that the direction of
                     an earnings surprise presents an incorrect view of the net effect of the announcement. For
                     example, suppose that a company announced that earnings unexpectedly fell 5% this quarter
                     because the company is spending on expanding production such that earnings will be up by
                     20% for several quarters. If one just looked at the current earnings figures, this would seem to
                     be a negative announcement. Yet, the market might easily view this news as positive on net.
                     Third, the consensus expectation for earnings may be incorrect because some analysts had not
                     updated their analysis prior to the earnings announcement or had highly idiosyncratic views that
                     skewed the average estimate.

                     Because earnings announcements are not days with no news, our expectations for price
                     movements in the “incorrect” direction are lower than those above. As a simple measure, we
                     remove those announcements with statistically significant movements in the “correct” direction
                     and assume that 4.8125% of the remaining earnings announcements should have a movement
                     in the “incorrect” direction merely by chance. Table 4 then shows the expected percentage
                     of earnings announcements with movements in the “incorrect” direction, using the market
                     model including the industry adjustment. In Table 4, we see that when looking at the S&P
                     500 Index, there is a notable fraction of earnings announcements with statistically significant
                     price movements in the “incorrect” direction, with 17.2% of all responses to non-zero earnings
                     announcements across all S&P 500 companies appearing to be in the “incorrect” direction
                     compared to 36.7% in the “correct” direction. Notably, the ratio of “incorrect” to “correct”
                     movements tends to fall as we move from Small to Medium to Large earnings announcements,
                     suggesting that the overall news content of announcements with larger earnings surprises
                     more closely aligns with the direction of the earnings surprise than is true for announcements
                     with smaller earnings surprises. This suggests that caution is required in interpreting the overall
                     direction of a news announcement relative to market expectations.19




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 Table 4. Excess Returns on Earnings Announcements1, Considering Directionality for 504 Companies in the
          S&P 500 Index, as of December 31, 2015,2 over the Period January 4, 2010 through December 31, 2015

 		Daily Returns Predicted Using the S&P 500 Index and SPDR Sector ETFs3

                                                              All Non-Zero                Small Non-Zero                Medium                        Large
                                                                Earnings                    Earnings                    Earnings                     Earnings
                                                            Announcements 4              Announcements 4             Announcements 4              Announcements 4

                                                                     (1)                          (2)                         (3)                           (4)		

 Assuming that there is a significant return if the excess return on the announcement day or the following day is statistically
 significant at the 5% level and is in the same direction as the earnings news:

 Total Number of Companies5,6                                       495                          487                         478                          448
 Average Number of Earnings                                        23.1                          10.7                         5.0                          8.6
 Announcements7

 Assuming that a “correct” movement is a statistically significant return on that day or the following day and in the same
 direction as the earnings announcement, and assuming that an “incorrect” movement is a statistically significant return
 in the opposite direction of the earnings news:

 Percent of Earnings Announcements                              36.7%                         33.1%                      38.4%                         40.5%
 with a Correct Movement
 Expected Percentage of Earnings                                  3.0%                         3.2%                        3.0%                         2.9%
 Announcements with an Incorrect Movement8
 Observed Percentage of Earnings                                 17.2%                        22.1%                       16.1%                        11.2%
 Announcements with an Incorrect Movement9
 Excess Percentage of Earnings                                   14.1%                        18.9%                       13.1%                         8.4%
 Announcements with an Incorrect Movement

 Excess percentage of earnings announcements with an “incorrect” movement for the median company:
                                                                 13.7%                        21.0%                       15.7%                        10.0%

 Notes and Sources:												
 Price data and dividend data obtained from FactSet Research Systems, Inc.							
 Returns were adjusted for dividends and the effective trading date of the earnings dates were used. 					
 1 Earnings announcement dates obtained from FactSet Research Systems, Inc.
 2 S&P 500 Index constituents, as of December 31, 2015, obtained from Bloomberg, L.P.
 3 Company stock price returns for each calendar year are predicted by regressing the daily logarithmic returns of the company’s stock on the daily logarithmic returns
   of the S&P 500 Index and the SPDR Sector ETF corresponding to the company’s GICS Sector Code over the previous calendar year. Stock price returns on January 4,
   2016, are predicted by regressing the daily logarithmic returns of the company’s stock on the daily logarithmic returns of the S&P 500 Index and the SPDR Sector
   ETF corresponding to the company’s GICS Sector Code, over the period: January 2, 2014, through December 31, 2014. The SPDR Technology Sector ETF (ticker:
   “XLK”) was used for companies with the GICS codes 45 (Information Technology) and 50 (Telecommunication Services).
 4 Earnings announcements where the EPS reported was exactly the same as the mean EPS estimate are excluded. Earnings announcements are classified as “Small,”
   “Medium,” or “Large” based on the absolute value of the I/B/E/S amount earnings-per-share (EPS) surprise reported divided by the company stock price on the
   report date. “Small” events have an absolute EPS surprise of less than or equal to 0.075% of the closing price of the stock on the report date, “Medium” events have
   an absolute EPS surprise greater than 0.075% of the closing stock price on the report date but less than or equal to 0.15% of the company price on the report date,
   and “Large” events have an absolute EPS surprise greater than 0.15% of the closing price on the report date. EPS surprises are calculated from the mean I/B/E/S EPS
   estimate for that earnings report.
 5 The following companies were excluded from the analyses in columns (1) to (4) because their shares began trading publicly after April 2014: CSRA, Inc., Hewlett
   Packard Enterprise Co., Synchrony Financial, Alphabet, Inc. (class C shares), Navient Corp., PayPal Holdings, Inc., Columbia Pipeline Group, Inc., and Baxalta, Inc. In
   addition, News Corp. was excluded from the analyses in columns (2) to (4) because of an inability to locate I/B/E/S EPS surprise data for 2010-2015.
 6 Values in this row represent the total number of companies with at least one earnings day of the type indicated in columns (1) to (4).
 7 Calculated for only companies with at least one earnings day of the given type.
 8 Expected Percentage is calculated by multiplying the probability of a statistically significant movement in the wrong direction by chance (4.8125%, calculated as
   0.025 * [0.95 + 0.975]) by the percent of announcements that did not have a “correct” movement.
 9 Calculated as the difference in percent of earnings announcements with a statistically significant movement when the direction of the movement does not matter
   and the percentage of earnings days with a statistically significant movement when the movement must be in the same direction as the earnings news.




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                     Conclusion

                     As has been well-documented in the academic literature, a large share of stock-price
                     movements cannot be substantially explained by identifiable news events. The analyses
                     in this paper examine a similar question, considering the fraction of news events that are
                     associated with statistically significant stock-price movements for individual companies
                     when the traditional event-study methodology is employed. The results show that when we
                     examine large companies and events that should be material to investors, such as relatively
                     large earnings surprises, only about half of those news announcements are associated with a
                     statistically significant stock-price movement. Notably, this result holds even though we allow
                     for two chances (the day of the news announcement and the following trading day) to find a
                     statistically significant price movement.

                     While these results are not surprising given the prior academic literature, they do suggest that
                     one should be careful in setting a priori expectations about how frequently one would expect
                     a stock price to respond to what may appear to be material news. If “material” were defined
                     with a very high bar, one would still presumably expect that most such material news would
                     be associated with a statistically significant price movement for stocks that trade in efficient
                     markets, though that bar might be reasonably high. Thus, assumed absolute standards about
                     how frequently stocks that trade in efficient markets should respond to news in a statistically
                     significant manner ignore both theoretical issues with such assumptions and empirical evidence.

                     Finally, we also see that one should be careful about assuming that the direction of a price
                     movement can always be easily inferred from a casual, or potentially even a careful, reading
                     of news. When examining earnings announcements, we see more statistically significant price
                     movements in the opposite direction of the earnings surprise than we would expect by chance
                     alone. This indicates that there may be additional information in earnings announcements
                     beyond just the overall surprise in the reported results, or that we have not properly understood
                     what market expectations were before the announcement. Again, the message is that one
                     should be careful in setting a priori expectations about the frequency and direction of how one
                     would expect a stock price to respond to what might appear to be material new information.




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                     References

                     * Senior Vice President, NERA Economic Consulting. I thank Marcia Kramer Mayer and Jordan Milev for comments
                         and Stefan Boettrich, Kyle Monk, John Shymansky, Shadman Torofder, and Ashutosh Venkatraman for their
                         contributions to the analysis. I also note that my colleagues at NERA and I have been involved in some of the cases
                         discussed in this paper.
                     1   Cammer v. Bloom, 711 F. Supp. 1264, 1287 (D.N.J. 1989).
                     2   See, for example, In re Accredo Health, Inc. Securities Litigation, 2006 WL 1716910 (W.D.Tenn.) (“As to the fifth
                         [Cammer] factor, plaintiffs offer the declaration of its expert, [ ], who opines that ‘material new information resulted
                         in an immediate response in Accredo’s stock price.’ [Plaintiff’s expert] Decl. ¶ 28. [Plaintiff’s expert] describes one
                         example[.]”) and In re The Mills Corp. Securities Litigation, 257 F.R.D. 101 (E.D. Va. 2009) [2009 BL 82258] (“A
                         finding of market efficiency for the preferred shares is further supported by the considerable price drop in Mills
                         preferred stock on August 11, 2006.”). In these cases, the reference to a single example of a stock-price movement
                         is the only basis given for satisfying the fifth Cammer factor (i.e., price response to new information).
                     3   In re PolyMedica Corp. Securities Litigation, 453 F. Supp. 2d 260, 270 (D. Mass. 2006).
                     4   Paul A. Ferrillo, Frederick C. Dunbar, and David Tabak, “The ‘Less Than’ Efficient Capital Markets Hypothesis:
                         Requiring More Proof from Plaintiffs in Fraud-on-the-Market Cases,” 78 St. John’s L. Rev. 81, 119-22 (2004).
                     5   This is the standard form of the FDT Test. One can also compare the magnitude of the stock-price movements
                         on the two types of days, for example. Different versions of the test might all point to the same conclusion
                         regarding price response to news for the same stock over the same time period, though that need not be the
                         case. The standard form of the FDT Test, looking at the fractions of news and non-news days with statistically
                         significant stock-price responses to news, is well-suited for determinations relevant to securities litigation because
                         it is more directly aimed at the binary question of whether a stock price responds to news. In particular, the FDT
                         Test examines whether any stock-price response is above the threshold for statistical significance, a result that has
                         often been taken in securities litigation to correspond to the binary question of whether investors should have been
                         able to rely on the price of the stock to reflect public information. An additional consideration is that examinations
                         of the magnitude of a stock-price response may be heavily driven by a few very large movements that raise the
                         average price response to news and may not be indicative of how the stock price would respond to typical news
                         or to news of lesser importance. This would be particularly problematic if, contrary to proper statistical technique,
                         the event ending the class period is included in the test and if the combination of a news event and large stock-
                         price movement following that event was part of the reason why the litigation was brought (i.e., there would be a
                         selection-bias issue in including such a day as a news event, as its inclusion would have been driven, at least in part,
                         by the fact that there was an associated stock-price movement). Still, a combination of various tests will typically be
                         helpful in either validating or challenging the broader applicability of a single test.
                     6   It is worth noting that after apparently making numerous errors in his initial report, the expert for plaintiffs first cited
                         to the FDT article in a second report. The court discounted this, stating, “Furthermore, I question [the expert]’s use
                         of these tests for the first time in a second and inconsistent event study.”
                     7   See, for example, Första AP-Fonden v. St. Jude Medical, Inc., Civil No. 12-3070 (JNE/HB) (D. Minn. Dec. 22, 2015).
                         (“[Defendants] point out, for example, that one iteration of [Plaintiffs’ expert’s] comparative analysis showed that
                         SJM stock responded to news in a statistically significant amount only 36.4% of the time.”). The court found that
                         the stock did trade in an efficient market.
                     8   See, for example, the Reference Guide on Statistics in the Reference Manual of Scientific Evidence, Third Edition,
                         Federal Judicial Center, 2011, p. 251 (“In practice, statistical analysts typically use levels of 5% and 1%. The 5%
                         level is the most common in social science, and an analyst who speaks of sig¬nificant results without specifying the
                         threshold probably is using this figure.” Internal footnote omitted.)
                     9   The authors “break down all news articles into either ‘unidentified news’ or an ‘identified news’ category based on
                         whether the article can be tied to a set of relevant events (broken down into 14 categories and 56 subcategories).
                         … Moreover, these 158 thousand stock-days are narrowed down further to stock-days defined as ‘complex’, either
                         by number of articles, number of events or disagreement in tone across articles.” (p.3) The finding of more than
                         just a chance number of news days associated with statistically significant returns “is much more pronounced for
                         identified news days associated with one of our three measures of complexity, i.e., multiple articles, multiple events
                         or disagreement across articles. Respectively, these days are 82.2%, 78.3% and 89.2% more likely to coincide
                         with extreme returns days.” That is, 36.44%, 35.66%, and 37.84% of the three types of “complex” news days,
                         respectively, are associated with the bottom and top 20% of stock-price returns.
                         News is identified as “all documents that pass through the Dow Jones Newswire from January 1, 2000 to December
                         31, 2009. For computational reasons, we limit ourselves to the S&P500 companies (with at least 40 days of
                         available data).” (p. 11)
                     10 The authors employ the Factiva database and “identify news for a firm using full-text searches for the firm’s name in
                         the headline or lead paragraph of articles.” (p. 3948)




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                     References

                     11 Due to the large dataset, we do not investigate whether news came out before or after the close of the market
                       for each event. However, if the news event occurred before the close of trading on the announcement day, then a
                       price movement solely on the following day would generally not be taken as an indication of market efficiency.
                     12 There would be a 95% chance of not having a statistically significant return on any day if we were considering
                       chance alone. Thus, the probability of not having a statistically significant return on two consecutive days is 95% ×
                       95%, or 90.25%, meaning that there is a 9.75% chance of having a statistically significant return on at least one of
                       two consecutive days due solely to chance.
                     13 Column (1) of Table 1 shows the fraction of S&P 500 companies that have different percentages of their earnings
                       announcements associated with statistically significant returns. For example, 2.0% of the companies have up to
                       20% of their earnings announcements associated with a statistically significant return while an additional 19.2% of
                       S&P 500 companies have between 20% and 40% of their earnings announcements associated with a statistically
                       significant return. The sum of the five entries in the middle block of the column will add to 100%, with any
                       apparent discrepancy due to rounding.
                     14 I/B/E/S, the Institutional Brokers’ Estimate System, is a commonly used data provider that collects, among other
                       information, analyst earnings estimates and calculates an average or consensus estimate that can be compared to
                       later-reported earnings. As earnings surprises are on a continuum, the Small, Medium, and Large categories are, of
                       course, set by arbitrary cutoffs solely for the purposes of exposition.
                     15 Here, we effectively assume that most earnings announcements are made after the close on the report date. An
                       alternative analysis that measures the earnings as a percent of the stock price the day before the announcement
                       yields similar results. In addition, alternative analyses that look at the absolute magnitude of the earnings surprise
                       in cents per share and others that use the S&P SmallCap 600 Index instead of the S&P 500 Index also yield similar
                       results to the main analyses in this paper. Results of alternative analyses are available from the author upon request.
                     16 One might be surprised that the percent of companies with more than 80% of news days having statistically
                       significant returns is higher for all three categories of earnings announcements (i.e., 10.5%, 16.1%, and 15.6%
                       for Small, Medium, and Large earnings announcements) than for earnings announcements overall (2.2%). A
                       similar result is seen with the percent of companies with no more than 20% of news days being associated
                       with statistically significant returns. These results are because there are fewer Small, Medium, or Large earnings
                       announcements than total earnings announcements, and with fewer announcements, there are more likely to be
                       companies with very few Small, Medium, or Large earnings announcements, making it easier for them to have, for
                       example, either 0% or 100% of those announcements be associated with statistically significant returns.
                     17 Note that here, we replace Small earnings announcements with Small Non-Zero earnings announcements.

                     18 This is calculated as the probability of (1) above (2.5% × 97.5%) plus the probability of (2) above (95% × 2.5%).
                       Note that if there is both a “correct” and an “incorrect” movement on the two days, the return is classified as being
                       in the “correct” direction overall.
                     19 This is even more likely to be relevant in situations where explicit expectations do not exist. For example, if a
                       company is sued for securities fraud several days after it made an announcement that caused its stock to fall, the
                       market may consider the filing of a securities-fraud lawsuit to be highly likely. In such a situation, the actual filing
                       could of course be negative news, but could also be positive news if the scope of the lawsuit (e.g., the time period
                       covered) is less than expected by the market.




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                     About NERA

                     NERA Economic Consulting (www.nera.com) is a global firm of experts dedicated to applying
                     economic, finance, and quantitative principles to complex business and legal challenges. For
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                     Contact
                     For further information and questions, please contact the author:

                     Dr. David I. Tabak
                     Senior Vice President
                     +1 212 345 2176
                     david.tabak@nera.com




                     The opinions expressed herein do not necessarily represent the views of NERA Economic Consulting or any other NERA
                     consultant. Please do not cite without explicit permission from the author.




                  Electronic copy available at: https://ssrn.com/abstract=2824565


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