Title: Politics Gets Personal: Effects of Political Partisanship and Advertising on Family Ties Authors: M. Keith Chen1*†, Ryne Rohla2* Affiliations: 1 Anderson School, University of California, Los Angeles, CA 90095, USA. 2 School of Economic Sciences, Washington State University, Pullman, WA 99164, USA. *Both authors contributed equally to this work. † Corresponding author. Email: keith.chen@anderson.ucla.edu. Abstract: Research on growing American political polarization and antipathy primarily studies effects on public institutions and political processes, ignoring private effects such as damaged family ties. Using smartphone-tracking data and precinct-level voting, we show that politicallydivided families shortened Thanksgiving dinners by 20-30 minutes following the divisive 2016 election. This decline survives comparisons with 2015 and extensive demographic and spatial controls, and more than doubles in media markets with heavy political advertising. These effects appear asymmetric: while Democratic voters traveled less in 2016, political differences shortened Thanksgiving dinners more among Republican voters, especially where political advertising was heaviest. Partisan polarization may degrade close family ties with large aggregate implications; we estimate 27 million person-hours of cross-partisan Thanksgiving discourse were lost in 2016 to ad-fueled partisan effects. One Sentence Summary: Cell-tracking shows that mixed-party families had shorter 2016 Thanksgivings, an effect exacerbated by political advertising. Introduction: American partisan antipathy has risen sharply over the past twenty-five years. Over 55% of Democrats and Republicans described “very unfavorable” feelings toward the opposing party in 2016, up from 17-21% in the mid-1990s (1). Spatial sorting along partisan lines produces increasingly homogeneous electoral “bubbles” at both state and local levels (2, 3). Political minorities within these bubbles become more reticent to participate in or reveal their party as polarization increases (4). Animosity toward political rivals is not limited to the ballot box; implicit partisan biases manifest in discriminatory decisions at a rate higher than racial or gender biases (5). In surveys, parents have become less tolerant of their children dating and marrying across partisan lines (6), and observed dating and marital behavior segregates on politics more strongly than on physical attributes or personality characteristics (7). Political polarization impacts economic decisions in the public sphere, including where to work and shop, at higher larger than those caused by race, ethnicity, or religion (8). We study whether politics strains close family ties by measuring family gathering durations. After the historically divisive and stressful (9) 2016 presidential election, 39% of American families avoided political conversations during the holidays (10). Aversion to family political discussions largely spans both party and socioeconomic lines (10). In this context we study Thanksgiving, which in US election years, brings together family members with differing political views at a time of partisan salience. Anecdotal evidence suggests that many altered or canceled Thanksgiving plans in the wake of the 2016 election (11). Other families cut short their dinners if political arguments arose. Most political-personal studies rely on survey data, and lack the ability to broadly measure inflamed partisan antipathy and its effect on real-world behaviors such as spending time with friends and family. This study analyzes how political differences affected 2016 Thanksgiving dinners through the merging of two novel datasets. A unique collection of smartphone location-tracking data from more than ten million Americans allows observation of actual (not self-reported) movement behavior, at extremely precise spatial and temporal levels. We combined this with a database of the national precinct returns for the 2016 presidential election to impute individual political leanings at the finest spatial resolution legally possible. By comparing the partisan bend of an individual’s home location and where they attended Thanksgiving dinner, we can test the relationship between political disagreement and time expenditure. To further isolate the particular effect of election-year political partisanship, we compare time spent at Thanksgiving in 2016 with the Thanksgiving of the year before. That comparison suggests that our measured effect really is the result of heightened political rhetoric, and not an artifact of politically-correlated demographic or spatial sorting. Finally, since political advertising polarizes opinions (12) and media coverage of polarization heightens dislike for opposing parties (13), we compare partisan rifts between families who live within a few miles of each other but on opposite sides of media-market boundaries, and find political advertising more than doubles our measured Thanksgiving effects. Data Collection and Validation: We collected precinct-level results for the 2016 presidential election through internet scraping and by contacting Secretaries of State, Boards of Election, and other statewide and county-wide electoral authorities. For states that do not centrally compile precinct-level election results, we contacted individual County Clerks by email, phone, fax, or in person. The resulting dataset covers over 172,000 precincts in 99% of counties and over 95% of all votes cast in the race. Finally, we matched these vote totals to precinct polygonal shapefiles using Geographic Information Systems (GIS) software. Our data on political advertising come from Kantar Media’s Campaign Media Analysis Group as reported by the Center for Public Integrity (14). These data count every US presidential-level general election television ad aired in each of the 210 Nielsen Designated Market Areas after June 12, 2016, including ads purchased either directly by campaigns or by outside groups such as Political Action Committees. Additional demographic data from the Census Bureau’s 2012-2015 American Community Survey formed the basis of other control variables. Location tracking data comes from Safegraph, a company that aggregates location information from numerous smartphone apps. The data consist of “pings”, each of which identify the location (latitude and longitude) of a particular smartphone at a moment in time. Safegraph tracks the location of more than 10 million Americans’ smartphones, and our core analysis focusses on the more than 17 trillion pings Safegraph collected in the continental United States in November of 2016. To merge these data, we first form a proxy for each smartphone owner’s “home”, which both links that person to a voting precinct and determines whether a person ate Thanksgiving dinner away from home. Home locations are determined by looking at where each person in our sample is most frequently between 1 and 4am. If a person has a consistent early morning location over the three weeks before Thanksgiving, we use this location as a simple proxy for their “home”. This procedure identifies the home location of over 5 million people in the November Safegraph sample, and we link these locations with their corresponding voting precinct, two-party vote share, and census demographics using GIS software. An individual’s location for Thanksgiving is constructed based on their modal location between 1 and 5pm that day. If this location differs from the individual’s home, we assume that they traveled for Thanksgiving, and measure the amount of time that they spent at their Thanksgiving location for our duration analysis. By construction, this sample is only representative of the estimated 77% of Americans who own smartphones, which opens the question of whether our sample is politically representative of the American electorate as a whole. We test this by assigning to each person in our sample a voting ratio proportional to the 2016 two-party vote share of their home precinct. If a person lives in a precinct which recorded 150 Clinton and 50 Trump votes, for example, that person would be assigned 0.75 Clinton and 0.25 Trump votes. Figure 1(B) compares these votes against actual 2016 two-party vote shares for each state. The degree to which these points track the 45 degree line represents a joint test of the political representativeness of the Safegraph data, and the unbiasedness of our home-to-precinct likely-vote imputation. Our imputed votes are accurate to within 1 percent in 33 states and within 5 percent in all states. At a national level the data add up to a Democratic vote share of 50.3%, compared to the actual share of 51.1%. Empirical Analysis: Our first analysis examines whether conditional on traveling for Thanksgiving dinner, the partisan distance between the traveling and hosting households affects the dinner’s duration. For this we restrict our sample to households who were home both in the morning and the night of Thanksgiving, but who traveled for Thanksgiving dinner. This restricts our analysis to families who were likely able to control the duration of their visits. In Table 1 we estimate the following equation: durationij = α + β mismatchij + γ Fij + εij where mismatchij = Pi (1 – Pj) + (1 – Pi) Pj In this specification, durationij is the minutes traveler i spent with host j on Thanksgiving, and Fij is a set of fixed-effects that form groups of people for comparison defined by the pair of home / travel locations for persons i and j. Pi and Pj are the two-party vote shares of the precincts associated with home precincts for i and j, Pi = (demi / (demi + repi)). Using Pi and Pj as imputed vote probabilities, mismatchij is the imputed probability that persons i and j voted for different candidates in 2016. In all tables, regressions running from left to right control for progressively finer (i,j) location pairs culminating in 5-digit geohash boxes, a global grid of rectangular areas roughly 1.5 miles per side. To control for likely confounds such as demographics, distance, and travel time, our regressions compare Thanksgiving durations only between families that live and eat in the same pair of locations. For example, regression 3 compares two families if and only if they both live in zipcode X and visit zipcode Y, or vice versa. β is the coefficient of interest, measuring the difference in Thanksgiving durations between families that fall within the same Fij comparison groups, but some of whose votes matched and some of whose votes mismatched. Standard errors are clustered at the level of these comparison groups. We choose to use progressively tighter spatial controls to control for both demographics and travel distance simultaneously, since individual characteristics of people in our sample are inferred from spatial characteristics such as residential location. In online tables (available upon request) we report statistically identical results when demographics such as race, age, education, income, and employment are controlled for separately. Results in Table 1 indicate that despite fixed effects, which aggressively control for both travel distance and location-correlated demographics, families that were likely to have voted differently spent between 20 and 30 fewer minutes with each other; with Thanksgiving dinner averaging 4.1 hours. Tellingly, as we add finer spatial controls, our estimate of β increases in magnitude, suggesting that the measured decline in dinner duration is, if anything, an underestimate of the true effect of partisan mismatch. Table 2 separates the effects of the two components of mismatchij, [Pi (1 – Pj) and (1 – Pi) Pj]. This can be interpreted as separately measuring the effect of voting disagreement on Democratic voters visiting Republican households, and vice versa. Intuitively, this compares families within the same Fij pair, and asks if whether voting disagreement asymmetrically affects liberal travelers going from i to j, or more conservative travelers going from j to i. Table 2 suggests that conditional on traveling, travelers from Democratic precincts do not significantly shorten their visits to Republican hosts, while Republican-precinct travelers shortened their visits by over 40 minutes. Table 3 investigates whether these effects interact with local political advertising, and finds that, on average, Thanksgiving dinners are further shortened by around 1.5 minutes for every thousand political advertisements aired in the traveler’s home media market. In swing states such as Florida, media markets saw over 25 thousand ads over the course of the campaign, implying a 1.2 hours shorter Thanksgiving for vote-mismatched families. Consistent with our finding that advertising appears to heighten the partisan effect of the 2016 election on Thanksgivings, Table S1 gives the same analysis and regressions a year prior and finds no Thanksgiving-shortening effect, presumably at a time when political antipathy was less salient and polarizing. Continuing this comparison of 2015 and 2016, Figure S1 examines whether conditional on choosing to travel, families appear to have biased their choice of destinations to lower the political divide between guest and host, between 2015 and 2016. Figure S1 demonstrates that for families that traveled in both 2015 and 2016 —the strongest possible control for demographic and spatial confounds— there is no appreciable difference in the distribution of likelihood of political mismatch. Finally, tables S2 and S3 estimate linear probability models for the choice whether to travel for Thanksgiving dinner, in both 2015 and 2016. When comparing matched families living within a mile and a half of each other, Democratic voters reduced their likelihood of travel between 2015 and 2016 by 5 percentage points more than comparable Republican voters, an effect that increases significantly in areas with heavy political advertising. Following the 2016 election, anecdotal media reports (11) and online social media behavior (15) demonstrated an avoidance of political confrontations among Democratic voters, findings our study corroborate. Republicans, however, were more sensitive to partisan differences at Thanksgiving dinners. Aggregating across the 77% of American adults who own smartphones (16), our results suggest partisan differences cost American families 62 million person-hours of Thanksgiving time, 56.8% from individuals living in Democratic precincts and 43.2% from Republican precincts. Political advertising eliminated an additional 3.3 million person-hours, 52.8% from Democratic precinct residents and 47.2% from Republican residents. We estimate 27 million person-hours of cross-partisan discourse were eliminated, which may provide a feedback channel by which partisan antipathy reduces opportunities for close cross-party conversations. References and Notes 1. Pew Research Center, “Partisanship and political animosity in 2016.” (June 22, 2016); people-press.org/2016/06/22/partisanship-and-political-animosity-in-2016. 2. D. Wasserman, “Purple America has all but disappeared.” (FiveThirtyEight, March 8, 2017); fivethirtyeight.com/features/purple-america-has-all-but-disappeared. 3. A. Agadjanian, “The decline of competitive precincts from 2008 to 2016.” (Decision Desk HQ, March 30, 2017); decisiondeskhq.com/data-dives/the-decline-of-competitiveprecincts-from-2008-to-2016. 4. R. Perez-Truglia, G. Cruces, Partisan interactions: evidence from a field experiment in the United States. J. of Pol. Econ. 125, 1208-1243 (2017). 5. S. Iyengar, S. Westwood, Fear and loathing across party lines: new evidence on group polarization. Am. J. of Pol. Sci. 59, 690-707 (2015). 6. S. Iyengar, G. Sood, Y. Lelkes, Affect, not ideology: a social identity perspective on polarization. Pub. Opin. Quart. 76, 405-431 (2012). 7. J. Alford, P. Hatemi, J. Hibbing, N. Martin, L. Eaves. The politics of mate choice. J. of Pol. 73, 362-379 (2011). 8. C. McConnell, Y. Margalit, N. Malhotra, M. Levendusky, The economic consequences of partisanship in a polarized era. Am. J. of Pol. Sci., in press, (available at web.stanford.edu/~neilm/Economic_Consequences_Final_Identified.pdf). 9. American Psychological Association, “Stress in America: U.S. presidential election 2016.” (October 13, 2016); apa.org/news/press/releases/stress/2016/presidentialelection.pdf 10. Pew Research Center. “How Americans are talking about Trump’s election in 6 charts.” December 22, 2016. pewresearch.org/fact-tank/2016/12/22/how-americans-are-talkingabout-trumps-election-in-6-charts. 11. S. Tavernise, K. Seelye, “Political divide splits relationships—and Thanksgiving, too.” (The New York Times, November 15, 2016); nytimes.com/2016/11/16/us/politicaldivide-splits-relationships-and-thanksgiving-too.html 12. S. Ansolabenhere, S. Iyengar, Going Negative: How Political Advertisements Shrink & Polarize the Electorate (Free Press, 1996) 13. M. Levendusky, N. Malhotra, Does media coverage of partisan polarization affect political attitudes? Pol. Comm. 33, 283-301 (2016). 14. C. Zubak-Skees, “Tracking TV ads in the 2016 presidential race.” (The Center for Public Integrity, October 25, 2016); publicintegrity.org/2016/01/21/19164/tracking-tv-ads-2016presidential-race 15. D. Cox, R. Jones, “’Merry Christmas’ vs. ‘Happy Holidays’: Republicans and Democrats are polar opposites.” (Public Religion Research Institute, December 19, 2016); prri.org/research/poll-post-election-holiday-war-christmas 16. L. Rainie, A. Perrin, “10 facts about smartphones as the iPhone turns 10.” (Pew Research Center, June 28, 2017); pewresearch.org/fact-tank/2017/06/28/10-facts-aboutsmartphones Acknowledgments: The authors would like to thank seminar participants at UCLA, Northwestern, Simon Fraser, and Stanford Universities for helpful comments, and A. Hoffman, R. Squire and N. Yonack at Safegraph for data access and technical assistance. All data and code are available from the corresponding author by request. Neither author has any competing interests or funding sources related to this study. List of Supplementary Materials: Figure S1 Tables S1-S3 B 1 DC 0.9 Sampled Clinton Vote Share Fig. 1. Sampling and imputation validation. (A) Shows the results of the 2016 US presidential election, by precinct. (B) Jointly tests the representativeness of our celltracking data and the success of our simple vote-imputation process using voter precinct matching. For each state, the x-value is the actual two-party vote share in the 2016 election, and the y-value is the vote share obtained by assigning to each tracked smartphone the vote share of its imputed precinct. This produces a predicted national share of 0.503 for Clinton, while the actual vote share was 0.511. 0.8 0.7 California Hawaii 0.6 Nevada 0.5 New Mexico 0.4 Alaska Mississippi Alabama W. Virginia 0.3 Wyoming 0.2 0.1 0 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 2016 Clinton Vote Share 0.9 1 Variable: Prob. of political mismatch Observations: R-squared: Fixed-Effects: Num. of Groups: 1 Thanksgiving Duration (min) -13.02*** (1.990) 2 Thanksgiving Duration (min) -20.39*** (3.643) 3 Thanksgiving Duration (min) -22.18* (8.657) 4 Thanksgiving Duration (min) -26.94♦ (15.35) 583,071 0.0001 none 583,071 0.0552 county pairs 23,375 583,071 0.436 zip-code pairs 245,004 583,071 0.647 geohash-5 pairs 356,479 Table 1. Effect of political mismatch on Thanksgiving duration. Each column is an estimate of the effect of voting disagreement on the length of Thanksgiving dinner in 2016. All regressions are fixedeffect linear regressions, where fixed effects control for the pair of locations where an individual lives and ate Thanksgiving dinner. Regressions running from left to right control for progressively finer pairs of areas, culminating in 5-digit geohash boxes, a grid of boxes roughly 1.5 miles per side. For example, regression three compares families that live and ate in the same pair of zip codes, and can be interpreted as saying that within these comparison groups, opposite-voting families had 22minute shorter Thanksgiving dinners. The number of comparison groups these fixed-effects entail is listed for each regression. The mean duration of Thanksgiving dinner was 245 minutes, and the average probability of opposite-voting political mismatch was 0.44 with a SD of 0.10. Standard errors are clustered at the level of the fixed-effect and reported in parentheses, with significance levels: *** p<0.001, ** p<0.01, * p<0.05, ♦ p<0.1. Variable: Prob. D → R trvlr → host Prob. R → D trvlr → host Observations: R-squared: Fixed-Effects: Num. of Groups: 1 Thanksgiving Duration (min) 2.882 (2.290) -29.63*** (2.316) 2 Thanksgiving Duration (min) -5.024 (3.807) -36.27*** (3.963) 3 Thanksgiving Duration (min) -3.097 (9.067) -41.04*** (9.050) 4 Thanksgiving Duration (min) -12.03 (15.91) -43.95** (16.34) 583,071 0.0004 none 583,071 0.0555 county pairs 23,375 583,071 0.436 zip-code pairs 245,004 583,071 0.647 geohash-5 pairs 356,479 Table 2. Asymmetric effects of political mismatch. Each column is an estimate of the effect of voting disagreement between travelers and hosts (Dem to Rep and Rep to Dem) on the length of Thanksgiving dinner in 2016. All regressions are fixed-effect linear regressions, where fixed effects control for the pair of locations where an individual lives and ate Thanksgiving dinner. For example, regression three compares families that live and ate in the same pair of zip codes, and can be interpreted as saying that within these comparison groups, Republican-voting travelers leave Thanksgiving dinner over 40 minutes sooner if their hosts voted Democratic, while Democrat-voting travelers did not significantly shorten their stays at Republican-hosted dinners. The number of comparison groups these fixed-effects entail is listed for each regression. The mean duration of Thanksgiving dinner in 2016 was 245 minutes (4.1 hours), and the average probabilities of Democratvoting individuals eating at a Republican-hosted dinner (and vice-versa) were 0.221 and 0.216, respectively, both with SD = 0.10. Standard errors are clustered at the level of the fixed-effect and reported in parentheses, with significance levels: *** p<0.001, ** p<0.01, * p<0.05, ♦ p<0.1. Variable: Prob. D → R trvlr → host Prob. R → D trvlr → host Political ads (1K ads / mrkt) Prob. D → R × Pol. ads Prob. R → D × Pol. ads Observations: R-squared: Fixed-Effects: Num. of Groups: 1 Thanksgiving Duration (min) 2.882 (2.290) -29.63*** (2.316) 2 Thanksgiving Duration (min) -5.024 (3.807) -36.27*** (3.963) 3 Thanksgiving Duration (min) 13.53*** (2.643) -17.76*** (2.658) 0.734*** (0.171) -2.386*** (0.403) -2.825*** (0.412) 4 Thanksgiving Duration (min) -1.821 (4.671) -30.97*** (4.756) 0.136 (0.319) -0.931♦ (0.562) -1.491* (0.632) 583,071 0.001 none 583,071 0.0555 county pairs 23,375 583,071 0.001 none 583,071 0.0556 county pairs 23,375 Table 3. Political advertising heightens partisan effects. Each column is an estimate of the effect of voting disagreement between travelers and hosts (Dem to Rep and Rep to Dem) on the length of Thanksgiving dinner in 2016, and whether political advertising heightens these effects. All regressions are linear regressions, where fixed effects control for the pair of locations where an individual lives and ate Thanksgiving dinner. Media markets in swing states like Florida saw over 25 thousand ads in 2016; in regression four this implies a doubling of the main 31-minute effect, and resulting in a Thanksgiving dinner of over an hour shorter for Republicans eating with Democratic hosts. The mean duration of Thanksgiving in 2016 was 245 minutes (4.1 hours), and the average probabilities of Democrat-voting individuals eating at a Republican-hosted dinner (and vice-versa) were 0.221 and 0.216, respectively, both with SD = 0.10. Standard errors are clustered at the level of the fixed-effect and reported in parentheses, with significance levels: *** p<0.001, ** p<0.01, * p<0.05, ♦ p<0.1. Supplementary Materials: Fig. S1. The (non)effect of partisanship on Thanksgiving destination choice. This compares the distributions of voting mismatch for Thanksgivings 2015 and 2016 for individuals who traveled in both years. (A) shows the probability distribution that a person who traveled in both years voted differently from their Thanksgiving hosts in 2015 and 2016. (B) and (C) show the two ways mismatch can occur; a Democratic traveler eating with a Republican host (B), or vice versa (C). T-tests confirm that conditional on traveling for Thanksgiving dinner, the partisan difference of travelers and hosts did not change significantly between 2015 and 2016. Variable: Prob. of political mismatch Observations: R-squared: Fixed-Effects: Num. of Groups: 1 Thanksgiving Duration (min) 38.05*** (8.178) 2 Thanksgiving Duration (min) 16.05 (12.02) 3 Thanksgiving Duration (min) -66.20 (111.3) 4 Thanksgiving Duration (min) -61.86 (182.5) 25,969 0.001 none 25,969 0.163 county pairs 4,578 25,969 0.841 zip-code pairs 22,301 25,969 0.915 geohash-5 pairs 24,030 Table S1. The (non)effect of partisanship on Thanksgiving 2015. Each column is an estimate of the effect of opposite-party voting on the duration of Thanksgiving dinner as measured in celltracking data in 2015. All regressions are fixed-effect linear regressions, where fixed effects control for the pair of locations where an individual lives and ate Thanksgiving dinner. Regressions running from left to right control for progressively finer pairs of areas, culminating in 5-digit geohash boxes, a grid of boxes roughly 1.5 miles per side. While the sample of tracked smartphones is much smaller in 2015, these regressions suggest that unlike the post-election Thanksgiving of 2016, there was no systematic relationship between political mismatch and the duration of Thanksgiving dinner in 2015. The mean duration of Thanksgiving dinner in 2015 was 200 minutes, and the average probability of opposite-voting political mismatch was 0.42 with a SD of 0.11. Standard errors are clustered at the level of the fixed-effect and reported in parentheses, with significance levels: *** p<0.001, ** p<0.01, * p<0.05, ♦ p<0.1. Variable: Post election (year = 2016) Home 2-party vote (Dem) PE × H2PV Observations: R-squared: Fixed-Effects: Num. of Groups: 1 Thanksgiving not at home 0.146*** (0.00354) -0.000771 (0.00580) -0.121*** (0.00599) 2 Thanksgiving not at home 0.145*** (0.00431) 0.0287** (0.00933) -0.116*** (0.00891) 3 Thanksgiving not at home 0.151*** (0.00345) 0.0695*** (0.00703) -0.122*** (0.00585) 4 Thanksgiving not at home 0.156*** (0.00374) 0.0586*** (0.00781) -0.128*** (0.00633) 2,025,855 0.005 none 2,025,855 0.0114 county 1,838 2,025,855 0.0335 zip code 30,237 2,025,855 0.0886 5-digit geohash 116,901 Table S2. Partisanship and Thanksgiving travel: 2015 & 2016. Each column is an estimate of the effect of political leanings on the choice to eat Thanksgiving dinner at home or away, and how this effect differs between the pre-election 2015 and post-election 2016 Thanksgivings. All regressions are fixed-effect linear probability regressions, where fixed effects control for the location of a person’s home. Standard errors are clustered at the level of the fixed-effect and reported in parentheses, with significance levels: *** p<0.001, ** p<0.01, * p<0.05, ♦ p<0.1. Variable: Post election (year = 2016) Home 2-party vote (Dem) PE × H2PV Political ads (1K ads / mrkt) PE × H2PV × Pol. ads H2PV × Pol. ads PE × Pol. ads Observations: R-squared: Fixed-Effects: Num. of Groups: 1 Thanksgiving not at home 0.139*** (0.00417) -0.0113♦ (0.00683) -0.109*** (0.00705) -0.00178*** (0.000529) -0.00303** (0.000963) 0.00266** (0.000927) 0.00170** (0.000545) 2 Thanksgiving not at home 0.139*** (0.00505) 0.0198♦ (0.0111) -0.104*** (0.0106) -0.00180** (0.000641) -0.00295** (0.00114) 0.00231* (0.00104) 0.00164** (0.000582) 3 Thanksgiving not at home 0.145*** (0.00410) 0.0606*** (0.00833) -0.111*** (0.00695) -1.65e-05 (0.00116) -0.00265** (0.000954) 0.00223* (0.00108) 0.00152** (0.000525) 4 Thanksgiving not at home 0.150*** (0.00446) 0.0499*** (0.00930) -0.118*** (0.00753) -0.000514 (0.00162) -0.00233* (0.00104) 0.00213♦ (0.00122) 0.00135* (0.000574) 2,025,855 0.005 none 2,025,855 0.0114 county 1,838 2,025,855 0.0335 zip code 30,237 2,025,855 0.0886 5-digit geohash 116,901 Table S3. Political advertising and Thanksgiving travel: 2015 & 2016. Each column is an estimate of the effect of political leanings on the choice to eat Thanksgiving dinner at home or away, and how this effect differs between the pre-election 2015 and post-election 2016 Thanksgivings, and between areas that saw more or less political advertising in 2016. All regressions are fixed-effect linear probability regressions, where fixed effects control for the location of a person’s home. For example, regression three can be interpreted as saying that in 2016, Democratic households significantly reduced their propensity for Thanksgiving travel relative to Republicans living in their same zipcode, and that this effect was much more pronounced for Democratic households that were exposed to large amounts of political advertising. Standard errors are clustered at the level of the fixed-effect and reported in parentheses, with significance levels: *** p<0.001, ** p<0.01, * p<0.05, ♦ p<0.1.