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Stock Market Reactions to Presidential Social Media Usage: Evidence from Company-Specific Tweets * Qi Ge Alexander Kurov Marketa Halova Wolfe § **** PRELIMINARY DRAFT: DO NOT CITE OR CIRCULATE **** First Draft: March 20, 2017 This Draft: May 4, 2017 Abstract Recent political developments in the United States offer a unique opportunity to examine the role of social media in the stock market. Specifically, we analyze the impact of tweets from President Trump’s official Twitter accounts from November 9, 2016 to February 28, 2017 that include a name of a publicly traded company. We find that these tweets move company stock prices, increase trading volume, and affect Bloomberg institutional investor attention and company-specific sentiment, with a stronger impact before the presidential inauguration. Keywords : Twitter, company-specific tweets, President Trump, stock price, trading volume, Bloomberg institutional investor attention, Bloomberg sentiment, event study JEL classification : G12, G14 * We thank seminar participants at Skidmore College for helpful comments. We also thank Chen Gu for research assistance. The opinions in this paper are those of the authors and do not necessarily reflect the views of Skidmore College or West Virginia University. Assistant Professor, Department of Economics, Skidmore College, Saratoga Springs, NY 12866, Phone: +1-518-580-8302, Email: [email protected] Associate Professor, Department of Finance, College of Business and Economics, West Virginia Univer- sity, P.O. Box 6025, Morgantown, WV 26506, Phone: +1-304-293-7892, Email: [email protected] § Assistant Professor, Department of Economics, Skidmore College, Saratoga Springs, NY 12866, Phone: +1-518-580-8374, Email: [email protected]

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Page 1: Stock Market Reactions to Presidential Social Media Usage ...lamacro.davidson.edu/wp-content/uploads/gravity... · Our study makes the following contributions. First, to our knowledge,

Stock Market Reactions to Presidential Social Media

Usage: Evidence from Company-Specific Tweets∗

Qi Ge † Alexander Kurov ‡ Marketa Halova Wolfe §

**** PRELIMINARY DRAFT: DO NOT CITE OR CIRCULATE ****

First Draft: March 20, 2017This Draft: May 4, 2017

Abstract

Recent political developments in the United States offer a unique opportunity to

examine the role of social media in the stock market. Specifically, we analyze the impact

of tweets from President Trump’s official Twitter accounts from November 9, 2016 to

February 28, 2017 that include a name of a publicly traded company. We find that

these tweets move company stock prices, increase trading volume, and affect Bloomberg

institutional investor attention and company-specific sentiment, with a stronger impact

before the presidential inauguration.

Keywords: Twitter, company-specific tweets, President Trump, stock price, tradingvolume, Bloomberg institutional investor attention, Bloomberg sentiment, event studyJEL classification: G12, G14

∗We thank seminar participants at Skidmore College for helpful comments. We also thank Chen Gu forresearch assistance. The opinions in this paper are those of the authors and do not necessarily reflect theviews of Skidmore College or West Virginia University.†Assistant Professor, Department of Economics, Skidmore College, Saratoga Springs, NY 12866, Phone:

+1-518-580-8302, Email: [email protected]‡Associate Professor, Department of Finance, College of Business and Economics, West Virginia Univer-

sity, P.O. Box 6025, Morgantown, WV 26506, Phone: +1-304-293-7892, Email: [email protected]§Assistant Professor, Department of Economics, Skidmore College, Saratoga Springs, NY 12866, Phone:

+1-518-580-8374, Email: [email protected]

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1 Introduction

Media coverage helps disseminate news by alleviating informational frictions. Past research

has extensively studied the role of traditional mass media in financial markets. Recent

topics include the role of local media (Engelberg & Parsons, 2011), the impact of newspaper

reports on the momentum of stock returns (Hillert, Jacobs, & Muller, 2014), sources of

news stories (Dougal, Engelberg, Garcia, & Parsons, 2012; Ahern & Sosyura, 2014), cross-

sectional evidence on media coverage and stock returns (Fang & Peress, 2009), newspaper

coverage and mutual fund investment decisions (Kaniel & Parham, 2017), and the role of

investor relations firms (Solomon, 2012). The rise and popularity of social media, such

as Facebook and Twitter, as alternative media building on real-time information delivery

and social networking, have understandably attracted scholarly attention and allowed us

to broaden our understanding of the impact of media on the financial markets. Exploring

a rich body of social media messages, many existing studies within this growing strand

of research apply linguistic content analysis to measure investor sentiment and consider

its impact in the financial markets (Bollen, Mao, & Zeng, 2011; Siganos, Vagenas-Nanos,

& Verwijmeren, 2014; Sprenger, Sandner, Tumasjan, & Welpe, 2014; Bartov, Faurel, &

Mohanram, 2016; Azar & Lo, 2016). Recent political developments in the United States

offer a unique opportunity to further advance this literature by examining the stock market

responses to presidential social media messages that target specific companies.1

Donald J. Trump, the 45th President of the United States, was elected on November

8, 2016. President Trump has broken with the long-standing tradition of presidents and

other high-ranking government officials to abstain from making comments about specific

companies. In particular, President Trump has utilized Twitter to target specific companies

in his tweets about industrial policy. To motivate our study, Figure 1 shows an example

of the impact on the price and trading volume of Toyota’s American depositary receipts

1Researchers have also recently examined other aspects of social media’s role in the 2016 presidentialelection. For example, Allcott and Gentzkow (2017) study the importance of social media in disseminatingfake news during the 2016 presidential election.

1

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(ADRs) in the 60-minute window around 13:14 EST on January 5, 2017 when President

Trump tweeted: “Toyota Motor said will build a new plant in Baja, Mexico, to build Corolla

cars for U.S. NO WAY! Build plant in U.S. or pay big border tax.” The figure suggests that

the trading volume spiked, and price dropped by more than one dollar immediately following

President Trump’s tweet. While no systematic inference can be drawn based on this figure

alone, it is plausible that investors respond to these firm-specific tweets.

Figure 1: Toyota ADR (TM) on January 5, 2017

Stock price Trading volume

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Toyota (TM) on January 5, 2017

The figure shows the price and trading volume of Toyota ADRs (TM) in the 60-minute window around 13:14on January 5, 2017 when President Trump tweeted: “Toyota Motor said will build a new plant in Baja,Mexico, to build Corolla cars for U.S. NO WAY! Build plant in U.S. or pay big border tax.” The figure isconstructed using minute-by-minute transaction data from Genesis Financial Technologies.

In this study, we analyze the impact of all tweets from @realDonaldTrump and @POTUS

Twitter accounts used by President Trump that include a name of a publicly-traded company

from November 9, 2016 to February 28, 2017. We find that the tweets move company stock

prices, increase trading volume, and affect Bloomberg institutional investor attention and

company-specific sentiment. We also find that the impact was stronger before the President-

elect was inaugurated on January 20, 2017. During the pre-inauguration period, the tweets

on average move the company stock price by approximately 1.16% and increase trading

volume by approximately 48% on the day of the tweet.

2

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Our study makes the following contributions. First, to our knowledge, it is the first

to document the stock market reactions to a government official’s direct, unscheduled, and

non-neutral comments targeting specific companies. The paper thus contributes to our

understanding of the role of social media in the financial markets and to the broader literature

on the impact of media coverage and news announcements. Second, within the growing

strand of social media studies, the novelty of our study lies in the fact that our events are

defined by presidential social media messages which often came as surprises. This stands

in contrast to prior studies that derive investor sentiment from social media reactions to

pre-scheduled events from the financial markets or the overall economy, such as quarterly

earnings announcements (Bartov et al., 2016) and monetary policy announcements (Azar &

Lo, 2016).

The paper is organized as follows. Section 2 surveys the related literature. Sections 3

and 4 describe the data and methodology, respectively. Section 5 presents the empirical

results. Section 6 concludes with a discussion of future research questions.

2 Related Literature

Our study is related to a number of research channels that consider the impact of news

announcements and media attention in financial markets and is most akin to the growing

strand of literature on the role of social media in financial markets.2 Previous studies tend to

focus on measuring Twitter message volumes as proxies for news arrivals and investors pro-

cessing relevant information. Linguistic textual analysis of related social media messages has

often been applied to quantify investor sentiment. Much of the existing literature considers

the (causal) relation between investor sentiment and stock returns at market or individual

stock level, where the sentiment can be derived from opinions posted on online investment

forums (Chen, De, Hu, & Hwang, 2014), Facebook posts (Karabulut, 2013; Siganos et al.,

2A closely related but non social media based stream of literature studies Google search queries as a proxyfor investor attention, for example, Da, Engelberg, and Gao (2011) and Joseph, Wintoki, and Zhang (2011).

3

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2014), and Twitter feeds (Bollen et al., 2011; Sprenger et al., 2014; Mao, Counts, Bollen, et

al., 2015).

News announcements provide the foundation to event studies in economics and finance.

Despite a voluminous literature on firm-specific news events (see MacKinlay (1997) for a

survey of event study literature) and macro announcements (for example, Balduzzi, Elton,

& Green, 2001; Andersen, Bollerslev, Diebold, & Vega, 2003; Kurov, Sancetta, Strasser, &

Wolfe, 2017), existing social media studies rarely seek to examine the role of social media

around specific news announcements. Notable exceptions include Bartov et al. (2016) that

investigate the impact of pre-earnings announcement opinions expressed via tweets on post-

announcements returns, and Azar and Lo (2016) that study how tweets related to the Federal

Open Market Committee (FOMC) meetings can predict future returns. It is worth noting

that both studies consider pre-scheduled news events. On the other hand, a considerable

number of news announcement studies concerns the impact of unanticipated news events (for

example, Brooks, Patel, & Su, 2003; Knittel & Stango, 2013). Our paper thus differs from

and contributes to existing social media studies by investigating the stock market impact of

the unexpected firm-specific comments made by the President via social media.

More broadly, to our knowledge, no prior studies have documented the financial market

impact of government officials’ comments, whether through traditional media or social me-

dia, targeting particular companies. Such vacuum is understandable given that government

leaders typically refrain from targeting specific companies in their public communications.

The popularity of social media, combined with the newest political developments in the

United States, gives us a unique opportunity to bridge this gap in the literature by con-

sidering President Trump’s tweets as a platform for firm-specific news and examining their

impact on the stock market.

4

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3 Data

Section 3.1 describes the presidential tweets data followed by a description of the dependent

variables in Section 3.2.

3.1 Twitter Data

Table A1 lists all tweets from @realDonaldTrump and @POTUS Twitter accounts3 that include

a name of a publicly-traded company from November 9, 2016 to February 28, 2017. We use

November 9, 2016 as the beginning of the sample period because the presidential election

took place on November 8, 2016.4 The first such tweet appears on November 17, 2016. The

last such tweet appears on February 17, 2017.

Most of the tweets are posted outside of the U.S. stock market open hours from 9:30 to

16:00 EST on business days – in the early morning, in the evening, on weekends or holidays

– such as a tweet about Rexnord on December 2, 2016 at 22:06. Therefore, to analyze the

impact of the tweets on the stock market, we use daily (rather than intraday) stock prices,

trading volume, institutional investor attention, and company-specific sentiment.

When there are multiple tweets on the same day, the daily prices, trading volume, institu-

tional investor attention, and company-specific sentiment combine the effects of the multiple

tweets. These multiple tweets can take place over several hours (for example, tweets about

Carrier on November 29 and 30, 2016) or within a couple of minutes when a longer message

is split up into multiple tweets (for example, tweets about SoftBank on December 6, 2016

at 14:09 and 14:10), which arises from Twitter restricting the length of each tweet to 140

characters. The last column of Table A1 shows how multiple tweets combine into a single

3@POTUS with approximately 16 million followers is the official Twitter account of the President of theUnited States that became available to President Trump after inauguration on January 20, 2017. Tweetscreated by President Obama were archived into @POTUS44 account. @realDonaldTrump with approximately27 million followers is President Trump’s personal account that continues to be used. As indicated inTable A1, majority of the tweets in our sample were posted on @realDonaldTrump with only four tweetsposted on @POTUS.

4We exclude tweets about media companies such as CNN (owned by Time Warner Inc) and New YorkTimes (owned by the New York Times Company) because their impact on the stock market is complicatedby President Trump’s ongoing feud with media.

5

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event.

The column Code in Table A1 classifies the tweets as negative (-1) if the tweet is a

“threat” and positive (1) if the tweet is a “praise”. For example, we interpret the tweet

about Rexnord on December 2, 2016 “Rexnord of Indiana is moving to Mexico and rather

viciously firing all of its 300 workers. This is happening all over our country. No more!” as

negative (a “threat”) and the tweet about Ford on November 17, 2016 “Just got a call from

my friend Bill Ford, Chairman of Ford, who advised me that he will be keeping the Lincoln

plant in Kentucky - no Mexico” as positive (a “praise”).5

If a tweet mentions more than one company such as a tweet about General Motors and

Walmart on January 17, 2017 “Thank you to General Motors and Walmart for starting the

big jobs push back into the U.S.!, the tweet is listed twice to capture the impact on both

companies. This is important especially when a tweet is positive about one company and

negative about another company such as a tweet about Lockheed Martin and Boeing on

December 22, 2016 “Based on the tremendous cost and cost overruns of the Lockheed Martin

F-35, I have asked Boeing to price-out a comparable F-18 Super Hornet! that is negative

about Lockheed Martin but positive about Boeing. Our sample does not contain any days

with both positive and negative tweets about the same company. In two tweets about

Ford, General Motors and Lockheed Martin on January 18, 2017, the tone of the tweets is

ambiguous, so we exclude them. Our data set then includes 27 events. Six are classified as

a threat, and 21 are classified as a praise.

3.2 Market Data

We analyze the impact of the presidential tweets on company stock price, trading volume,

institutional investor attention, and company-specific sentiment. The price and trading

volume are obtained from Yahoo Finance. We employ the Bloomberg institutional investor

5This classification focuses on the tone of the tweet rather than potential economic impacts that are likelyto be complex. For example, a decision to keep a plant in the United States may be advantageous for acompany if it is able to negotiate incentives such as tax breaks or reduced regulation or disadvantageous ifit forgoes cost savings from relocating to a country with lower production costs.

6

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attention (IIA) measure described by Ben-Rephael, Da, and Israelsen (2016). Bloomberg

tracks how many times Bloomberg users read articles about a given company and search for

information about the company. Bloomberg records hourly counts, compares the counts in

the previous eight hours to previous 30 days and assigns a score of 0, 1, 2, 3 and 4 if the

average over the last eight hours is less than 80%, between 80% and 90%, between 90% and

94%, between 94% and 96%, or higher than 96%, respectively, compared to the previous 30

days. Following Ben-Rephael et al. (2016), we construct a binary measure of abnormal IIA

that equals 1 if IIA equals 3 or 4, and 0 otherwise, so that the abnormal IIA captures the

right tail of the IIA distribution, and the value of 1 represents an IIA shock.

The company-specific sentiment is constructed by Bloomberg for each stock based on

messages posted about the company on Twitter and StockTwits, a social media platform for

sharing information about stocks and markets. Bloomberg separates messages with company

tickers into three categories (positive, negative and neutral) and assigns confidence scores

using a proprietary algorithm. These scores are then aggregated to derive a measure of

sentiment for each company. This computation is performed every 30 minutes. The values

are averaged over 24 hours (from 9:30 a.m. on the previous day to 9:29 a.m. on the current

day) to compute daily sentiment which is then made available to Bloomberg users rescaled

to a range from -1 (the most negative sentiment) to +1 (the most positive sentiment).

4 Methodology

To analyze the impact of the presidential tweets on company stock prices, we use daily

closing stock prices, Pi,t, for each company i. We compute the holding period return for

each company as Ri,t =Pi,t−Pi,t−1

Pi,t−1. We compute excess return as the return for that company

in excess of the risk-free return, RFt, obtained from Kenneth French’s website, ERi,t =

Ri,t −RFt. Table 1 shows the summary statistics.

We estimate the standard Fama-French three-factor model (Fama & French, 1993) using

7

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Table 1: Summary Statistics

Absolute AbnormalAbsolute Value Abnormal Company- Institutional

Value Abnormal Abnormal Trading Specific InvestorReturn Return Return Return Volume Sentiment Attention

Median 0.108 0.726 -0.005 0.617 -0.061 0.000 0.000Mean 0.144 1.068 -0.006 0.930 0.080 -0.023 0.249Minimum -10.280 0.000 -9.617 0.001 -0.814 -0.987 0.000Maximum 9.682 10.280 6.881 9.617 10.858 0.980 1.000Std Dev 1.574 1.165 1.397 1.041 0.726 0.193 0.433

This table shows the summary statistics for return computed as Ri,t = (Pi,t − Pi,t−1)/Pi,t−1, the absolutevalue of the return, abnormal return computed as residuals from equation (1), the absolute value of abnormalreturn, abnormal volume computed as AVi,t = (Vi,t−VAvrg,t)/VAvrg,t, and Bloomberg measures of sentimentand abnormal institutional investor attention. Returns are expressed in percentage terms. The sample periodis from November 9, 2016 to February 28, 2017. The number of days is 75. The number of companies is15 for all variables except for the Bloomberg sentiment measure where data is not available for Rexnordcompany. The resulting number of panel observations is 1,125 except for the Bloomberg company-specificsentiment measure where the number of observations is 1,045.

OLS that regresses the excess return on the stock market return, RMt, minus the risk-free

return factor, the small-minus-big market capitalization factor, SMBt, and the high-minus-

low book-to-market ratio factor, HMLt:6

ERi,t = β0 + β1(RMt −RFt) + β2SMBt + β3HMLt + εi,t. (1)

Controlling for the stock market return is especially important since the overall market

increased during our sample period. We obtain residuals, ui,t, or abnormal returns, from

equation (1) for each company. We then estimate a fixed effects panel model:

ui,t = γ0 + γ1Ti,t + γi + vi,t, (2)

where γi accounts for the fixed effects and Ti,t is the Twitter variable described in Section 3.7

6This regression uses data from January 1, 2016 to February 28, 2017 to properly estimate the effect ofthe Fama-French factors on the excess return.

7In contrast to studies that analyze the impact of scheduled announcements (for example, Balduzzi etal. (2001), Andersen et al. (2003) and Kurov et al. (2017) on macroeconomic announcements) that have tosubtract market’s expectations from the actual released announcement values to compute the unexpectedcomponent of the announcement, our study does not have to subtract market’s expectations because the

8

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The number of days is 75. The number of companies is 15. The resulting number of panel

observations is 1,125. We use panel-corrected standard errors to account for cross-correlation

across stocks.

To analyze the impact of the presidential tweets on company stock trading volume, we

compute abnormal trading volume, AVi,t, for each company i as the difference between

trading volume Vi,t and mean trading volume of the previous five days divided by the mean

trading volume of the previous five days similarly to Joseph et al. (2011): AVi,t =Vi,t−VAvrg,t

VAvrg,t

where VAvrg,t =ΣJ

1 Vi,t−j

Jand J = 5. We then estimate a fixed effects panel model:

AVi,t = δ0 + δ1|Ti,t|+ δi + εi,t, (3)

where δi accounts for the fixed effects, and the absolute value of the Twitter variable is used

because both positive and negative tweets may increase the trading volume. We again use

panel-corrected standard errors to account for cross-correlation across stocks.

To analyze the impact of the presidential tweets on the Bloomberg measure of sentiment

about the company, we estimate the fixed effects panel model specified in equation (2) with

the sentiment variable in place of the residual, ui,t.

Lastly, to analyze the impact of the presidential tweets on the abnormal IIA measure

described in Section 3.2, we follow Ben-Rephael et al. (2016) and estimate a panel probit

model of the abnormal IIA measure on the absolute value of the Twitter variable |Ti,t| with

dummies for individual stocks.

5 Empirical Results

Section 5.1 reports the overall impact of the presidential tweets on company stock returns,

trading volume, and IIA. Section 5.2 discusses how the impact varies over time including the

impact on company-specific sentiment.

presidential tweets are unscheduled and unexpected.

9

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5.1 Stock Market Reactions to Presidential Tweets

Column (1) of Table 2 reports the impact of the presidential tweets on abnormal returns

in the full sample period from November 9, 2016 to February 28, 2017. The coefficient on

the Twitter variable indicates that presidential tweets on average move the company stock

price by approximately 0.78%: If the tweet is positive, the stock price tends to rise; if the

tweet is negative, the stock price tends to fall. This is an economically meaningful effect on

shareholder value because the median values of the absolute daily return and absolute daily

abnormal return are approximately 0.73% and 0.62%, respectively, per Table 1.

Table 2: Impact of Presidential Tweets

(1) (2) (3) (4)Abnormal Abnormal Abnormal Institutional Company-Specific

Return Trading Volume Investor Attention Sentiment

Full SampleTwitter variable 0.776*** 0.408*** 0.462*** 0.056

(0.257) (0.129) (0.082) (0.038)

Pre-InaugurationTwitter variable 1.157*** 0.476*** 0.521*** 0.078*

(0.306) (0.173) (0.327) (0.100)

Column (1) reports results for the fixed effects panel model specified in equation (2). Column (2) reportsresults for the fixed effects panel model specified in equation (3). Column (3) reports the marginal effectsof the probit model of the Bloomberg abnormal IIA discussed in Section 4. Column (4) reports resultsfor the fixed effects panel model specified in equation (2) with the market sentiment variable in placeof the residual, ui,t. Panel-corrected standard errors are shown in parentheses. *, **, and *** indicatestatistical significance at 10%, 5% and 1% levels, respectively. The full sample period is from November9, 2016 to February 28, 2017. The number of days is 75. The number of companies is 15. The resultingnumber of panel observations is 1,125. This includes 27 observations with tweets listed in Table A1. Thepre-inauguration sample period is from November 9, 2016 to January 19, 2017. The number of days is48. The number of companies is 12. The resulting number of panel observations is 576. This includes20 observations with tweets listed in Table A1. The market sentiment data is not available for Rexnordcompany, so the number of companies used in the analysis of Bloomberg company-specific sentiment is 14and 11 in the full sample period and pre-inauguration sample sub-period, respectively.

Column (2) reports the impact on abnormal trading volume. The coefficient on the

Twitter variable indicates that the presidential tweets (both positive and negative) on average

increase trading volume by approximately 41% compared to the average trading volume on

the previous five days.

10

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Column (3) reports the marginal effects of the probit model of the abnormal IIA. The es-

timate indicates that the presidential tweets (both positive and negative) on average increase

the probability of abnormal IIA by 46%. This suggests that President Trump’s company-

specific tweets capture attention of institutional investors.

5.2 Pre-Inauguration Period

Our sample period comprises two distinct sub-periods. The first sub-period is from the

presidential election to inauguration (November 9, 2016 to January 19, 2017). The second

sub-period is from the inauguration to the end of our sample period (January 20, 2017 to

February 28, 2017). We analyze whether the impact of the tweets is stronger during the pre-

inauguration period than during the full sample period. Table 2 presents the results for the

pre-inauguration period. There is a clear pattern of the coefficients on the Twitter variable

being higher than in the full sample period. The presidential tweets on average move the

company stock price by approximately 1.16% compared to 0.78% in the full sample period.

The tweets on average increase trading volume by approximately 48% compared to 41% in

the full sample period. Moreover, the tweets increase the probability of abnormal IIA by

52% compared to 46% in the full sample period.

The company-specific sentiment results seem to support this finding: The sentiment vari-

able is not significant in the full sample period but shows significance in the pre-inauguration

sub-period, with the tweets on average moving the Bloomberg sentiment measure by approx-

imately 0.08. Positive tweets have a positive effect on the sentiment whereas negative tweets

have a negative effect. The magnitude is economically meaningful given that the scale of the

sentiment variable is from -1 to 1.

It will be interesting to formally extend this sub-sample analysis to the post-inauguration

period when more data becomes available to determine whether the market reaction is indeed

lessening. Three potential explanations for this trend exist. First, the initial presidential

communications about specific companies took the markets by surprise, but the markets may

11

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have become accustomed to this new industrial policy targeting specific companies and do

not react as strongly any more. Second, Twitter was the primary channel of communicating

with the markets for the President-elect before inauguration. Other channels have been in

effect since the inauguration such as presidential executive orders, press releases, and press

briefings. These other channels could lessen the Twitter impact if investors consider them

more influential in setting the tone of the presidential industrial policy. Third, some of the

post-inauguration tweets were posted on the @POTUS account, which may differ in impact

from the @realDonaldTrump account since the two accounts differ in the number and perhaps

even characteristics of followers.

6 Conclusion

We analyze the impact of presidential tweets about specific companies on stock prices, trad-

ing volume, institutional investor attention, and company-specific sentiment. We find that

the tweets move company stock prices, increase trading volume and affect the institutional

investor attention and company-specific sentiment. These findings raise the question of

whether it is optimal for high-ranking government officials to communicate industrial policy

via Twitter where unexpected announcements can potentially instantly create or wipe out

millions of dollars in shareholder value. If this communication channel does become the

mainstay of presidential industrial policy, it will be important to implement procedures pre-

venting premature dissemination of the information similar to procedures utilized by other

government institutions that release market-moving announcements.

While our study documents the stock market impact of presidential social media usage,

this topic lends itself to further questions regarding the mechanisms when a larger sample

of presidential tweets becomes available. One avenue of future research could investigate

whether certain industry or firm-level attributes make the tweets particularly influential. For

example, some industries may be more influenced by the tweets due to their dependence on

12

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government contracts (for example, defense industry) or bailouts (for example, automobile

industry). A tweet about Nordstrom on February 8, 2017 “My daughter Ivanka has been

treated so unfairly by @Nordstrom. She is a great person – always pushing me to do the right

thing! Terrible!” provides anecdotal evidence that this may the case. Figure 2 shows that

the trading volume spiked, but after an initial dip the stock price increased in spite of the

tweet being negative about the company. This may be due to the company operating in the

retail industry that does not depend on government contracts or bailouts. Likewise, size of

the targeted company could play an important role in explaining the stock market impact

of the President’s social media messages.

Figure 2: Nordstrom (JWN) Stock on February 8, 2017

Stock price Trading volume

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f sha

res)

10:22 10:51 11:21

Nordstrom (JWN) on February 8, 2017

The figure shows Nordstrom (JWN) stock price and trading volume reaction in the 60-minute window around10:51 when President Trump tweeted “My daughter Ivanka has been treated so unfairly by @Nordstrom. Sheis a great person – always pushing me to do the right thing! Terrible!” The figure is constructed usingminute-by-minute transaction data from Genesis Financial Technologies.

Another possibility for future research could focus on the nature of the tweets. For

instance, one could investigate whether the impact is stronger when the President tweets

about a company for the first time. If there are multiple tweets about a given company, the

impact could also differ depending on whether the tweets rapidly follow each other or are

more distributed over time. If more tweets are posted on the @POTUS account, it will also be

13

Page 15: Stock Market Reactions to Presidential Social Media Usage ...lamacro.davidson.edu/wp-content/uploads/gravity... · Our study makes the following contributions. First, to our knowledge,

possible to test whether the two Twitter accounts differ in their impact. Linguistic textual

analysis could also be utilized to carefully analyze the tone of President Trump’s tweets.

Finally, if more tweets occur during the stock market open hours, a comprehensive analysis

of intraday data will reveal high-frequency price and trading volume moves that are likely

to be interesting based on anecdotal evidence in Figures 1 and 2.

14

Page 16: Stock Market Reactions to Presidential Social Media Usage ...lamacro.davidson.edu/wp-content/uploads/gravity... · Our study makes the following contributions. First, to our knowledge,

Table

A1:ListofTweets

Company

Ticker

Date

Tim

eTweet

Code

Event#

For

dF

11/1

7/16

21:0

1Ju

stgot

aca

llfr

om

my

frie

nd

Bil

lF

ord

,C

hair

man

of

Ford

,w

ho

ad

vis

edm

eth

at

he

wil

lb

eke

epin

gth

eL

inco

lnp

lant

inK

entu

cky

-n

oM

exic

o1

1

For

dF

11/1

7/16

21:1

5I

work

edh

ard

wit

hB

ill

Ford

tokee

pth

eL

inco

lnp

lant

inK

entu

cky.

Iow

edit

toth

egre

at

Sta

teof

Ken

tuck

yfo

rth

eir

con

fid

ence

inm

e!1

1

Car

rier

UT

X11

/24/

1610

:11

Iam

work

ing

hard

,ev

enon

Th

an

ksg

ivin

g,

tryin

gto

get

Carr

ier

A.C

.C

om

pany

tost

ayin

the

U.S

.(I

nd

ian

a).

MA

KIN

GP

RO

GR

ES

S-

Wil

lkn

owso

on

!1

2

Car

rier

UT

X11

/29/

1622

:40

Iw

ill

be

goin

gto

Ind

ian

aon

Thu

rsd

ayto

make

am

ajo

ran

nou

nce

men

tco

n-

cern

ing

Carr

ier

A.C

.st

ayin

gin

Ind

ian

ap

oli

s.G

reat

dea

lfo

rw

ork

ers!

13

Car

rier

UT

X11

/29/

1622

:50

Big

day

on

Thu

rsd

ayfo

rIn

dia

na

an

dth

egre

at

work

ers

of

that

won

der

ful

state

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wil

lkee

pou

rco

mp

an

ies

an

djo

bs

inth

eU

.S.

Th

an

ks

Carr

ier

13

Car

rier

aU

TX

11/3

0/16

13:2

1G

reat

inte

rvie

won

foxan

dfr

ien

ds

by

Ste

veD

oocy

w/

Carr

ier

emp

loye

e-w

ho

has

am

essa

ge

for

#P

EO

TU

Sre

alD

on

ald

Tru

mp

&#

VP

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TU

Sm

ike_

pen

ce.

13

Car

rier

aU

TX

11/3

0/16

15:0

0It

snot

un

com

mon

for

aR

epu

bli

can

tob

ep

ro-b

usi

nes

s.B

ut

Pre

sid

ent-

elec

tD

on

ald

Tru

mp

show

edT

ues

day

nig

ht

hes

pro

-work

er,

too,

by

savin

g1,0

00

job

sat

the

Carr

ier

pla

nt

inIn

dia

na.

13

Car

rier

UT

X11

/30/

1622

:48

Look

forw

ard

togoin

gto

Ind

ian

ato

morr

owin

ord

erto

be

wit

hth

egre

at

work

ers

of

Carr

ier.

Th

eyw

ill

sell

many

air

con

dit

ion

ers!

14

Car

rier

aU

TX

12/0

1/16

9:3

8G

etti

ng

read

yto

leav

efo

rth

eG

reat

Sta

teofIn

dia

na

an

dm

eet

the

hard

work

ing

an

dw

ond

erfu

lp

eop

leof

Carr

ier

A.C

.1

4

Rex

nor

dR

XN

12/0

2/16

22:0

6R

exn

ord

of

Ind

ian

ais

mov

ing

toM

exic

oan

dra

ther

vic

iou

sly

firi

ng

all

of

its

300

work

ers.

Th

isis

hap

pen

ing

all

over

ou

rco

untr

y.N

om

ore

!-1

5

Boei

ng

BA

12/0

6/16

8:5

2B

oei

ng

isb

uil

din

ga

bra

nd

new

747

Air

Forc

eO

ne

for

futu

rep

resi

den

ts,

bu

tco

sts

are

ou

tof

contr

ol,

more

than

$4

bil

lion

.C

an

cel

ord

er!

-16

Sof

tBan

ka,b

SF

TB

Y12

/06/

1614

:09

Masa

(Soft

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k)

of

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an

has

agre

edto

inves

t$50

bil

lion

inth

eU

.S.

tow

ard

bu

sin

esse

san

d50,0

00

new

job

s...

.1

7

Sof

tBan

ka,b

SF

TB

Y12

/06/

1614

:10

Masa

said

he

wou

ldnev

erd

oth

ish

ad

we

(Tru

mp

)not

won

the

elec

tion

!1

7

Exxon

Mob

ilX

OM

12/1

1/16

10:2

9W

het

her

Ich

oose

him

or

not

for

”Sta

te”-

Rex

Til

lers

on

,th

eC

hair

man

&C

EO

of

Exxon

Mob

il,

isa

worl

dcl

ass

pla

yer

an

dd

ealm

ake

r.S

tay

tun

ed!

18

Exxon

Mob

ilX

OM

12/1

3/16

6:4

3I

hav

ech

ose

non

eof

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tru

lygre

at

busi

nes

sle

ad

ers

of

the

worl

d,R

exT

ille

rson

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hair

man

an

dC

EO

of

Exxon

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il,

tob

eS

ecre

tary

of

Sta

te.

19

15

Page 17: Stock Market Reactions to Presidential Social Media Usage ...lamacro.davidson.edu/wp-content/uploads/gravity... · Our study makes the following contributions. First, to our knowledge,

Boei

ng

BA

12/2

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ase

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ase

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eral

Mot

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01/0

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ener

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exic

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ax

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da

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vin

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rap

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ico

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nt,

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an

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eto

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13

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dF

01/0

4/17

8:1

9T

han

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ord

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pp

ing

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exic

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ng

700

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his

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eb

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ore

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01/0

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13:1

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9:1

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01/1

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19

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16

Page 18: Stock Market Reactions to Presidential Social Media Usage ...lamacro.davidson.edu/wp-content/uploads/gravity... · Our study makes the following contributions. First, to our knowledge,

Lock

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17

Page 19: Stock Market Reactions to Presidential Social Media Usage ...lamacro.davidson.edu/wp-content/uploads/gravity... · Our study makes the following contributions. First, to our knowledge,

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