With these questions in mind, it seems important for a better understanding of the Trump phenomenon to (1) provide systematic empirical evidence about his personality reputation using well‐established measures, (2) compare and contrast his profile with those of other contemporary candidates and especially with the profile of other populist leaders, 2 and (3) discuss the implications of his personality in terms of communication style and (future) performance.

Yet this narrative is supported by very limited systematic evidence (but see Visser, Book, and Volk 2017 ; Hyatt et al. 2018 ; Nai and Maier 2018 ), which is detrimental for a complete understanding of Trump’s political figure and potentially for understanding his ascension to the supreme executive position (Ahmadian, Azarshahi, and Paulhus 2017 ). Furthermore, and probably more important in a comparative perspective, opinions about Trump’s personality in the press often forget to mention that many populist political figures in other countries are also consistently described as having abrasive, narcissistic, provocative, and offensive personalities. Indeed, it is rather common to see populists described in the media or the public debate as “drunken dinner guest[s]” (Arditi 2007 , 78) who rely on provocation and a more aggressive rhetoric, which sets them apart from other mainstream candidates. Acting at odds with social norms and taking pleasure in displaying “bad manners” (Moffitt 2016 ), populists tend to adopt a “transgressive political style” (Oliver and Rahn 2016 , 191) that “emphasises [sic] agitation, spectacular acts, exaggeration, calculated provocations, and the intended breech of political and socio‐cultural taboos” (Heinisch 2003 , 94), often by introducing “a more negative, hardened tone to the debate” (Immerzeel and Pickup 2015 , 350). Is Trump then simply the U.S. incarnation of a general political style based on an abrasive, provocative, and bombastic public figure? Or does he stand apart even when compared to his fellow populists?

Regardless of their diagnostic value, these considerations overlapped with a narrative that portrays Donald J. Trump—the billionaire, the candidate, and now the president—as impetuous and quick to anger, thin skinned, constantly lying, insecure, brazen, vulgar, uninterested in details, and boasting a grandiose sense of self and an exaggerated vision of himself and his accomplishments (Cillizza 2018 ). Many have suggested that Trump exhibits “sky‐high extroversion combined with off‐the‐chart low agreeableness [… and] grandiose narcissism” (McAdams 2016 ) and that he could possibly “present a diagnosis of psychopathy” (Olbermann 2016 ). His actions display “a messiah complex, no conscience, and lacks complete empathy” (Hoise 2017 ). Late‐night‐show hosts—from Stephen Colbert to Samantha Bee, Seth Meyers, and the Saturday Night Live team—have eagerly done their part to enforce that narrative.

In the first years of Trump’s presidency, the attention to his mental fitness for office took center stage in the public debate. Waving the flag of Section 4 of the Twenty‐Fifth Amendment of the U.S. Constitution, many of his detractors hoped to find in his alleged mental instability a way out from a dire situation or solace after a bitter defeat in 2016. Many psychiatrists also added their voice to the cacophony, in partial disregard of the “Goldwater Rule”—an ethical guideline according to which the mental health of a public figure should not be assessed unless a direct examination of him or her occurred 1 and which many now consider as outdated (Lilienfeld, Miller, and Lynam 2018 ).

The 2016 presidential election and its aftermath will undoubtedly keep political scientists, sociologists, communication scholars, and social psychologists busy for the upcoming decades. Much has already been told about why and how Donald Trump was able to beat the odds and force out a nourished camp of GOP contestants in the primaries and ultimately win the presidency—and we do not pretend to provide any additional empirical evidence. Rather, we simply argue that the personality of political leaders (and, by extension, Trump’s personality) is likely to matter. In an electoral context, candidates’ orientations and record now overshadow issue orientations and even partisanship (Swanson and Mancini 1996 ; Van Zoonen and Holtz‐Bacha 2000 ; Costa Lobo 2018 ); in addition, nonpolitical characteristics of a candidate (e.g., integrity, appearance, family circumstances, and personality traits) more and more dominate the overall evaluations of political leaders (e.g., Wattenberg 1991 ; Bittner 2011 ; Anderson and Brettschneider 2003 ; but see Wattenberg 2016 ). Due to the decline of party identification in modern democracies, an increasing number of voters are in urgent need of reliable and easy‐to‐access indicators serving as a heuristic in political decision making. For instance, several studies suggest that voters are more likely to like and support candidates with personalities that “match” their own (Caprara et al. 2003 ; Caprara and Zimbardo 2004 ; Fortunato, Hibbing, and Mondak 2018 ). Personality traits of political leaders are hard to hide (and often are covered by the media) and considered to be stable over time and closely related to behavior; they thus seem to be a perfect yardstick to predict what to expect from a candidate if elected. 3 Indeed, beyond mere electoral dynamics, the personality of political leaders has been shown to drive their accomplishments once in office (Rubenzer, Faschingbauer, and Ones 2000 ; Lilienfeld et al. 2012 ; Watts et al. 2013 ; Joly, Soroka, and Loewen 2018 ), for instance, in terms of policy accomplishments, relationships with the legislative branch, use of executive orders, and likelihood of unethical behavior. We return to this issue in the conclusion.

Turning to the Dark Triad, people high in narcissism exhibit a tendency toward grandiosity and flamboyant attention seeking; narcissists are prone to overconfidence and deceit (Campbell, Goodie, and Foster 2004 ), hypercompetitiveness (Watson, Morris, and Miller 1998 ; O’Boyle et al. 2012 ), reckless behavior, and risk taking (Campbell, Goodie, and Foster 2004 ) and are perceived as bold, aggressive, and often even as discourteous. Narcissists are confident enough in their capacities to boldly turn the odds in their favor, being particularly “adept at persuading others to agree with them” (Goncalo, Flynn, and Kim 2010 ). Watts et al. ( 2013 ) showed, for instance, that grandiose narcissism is associated, in U.S. presidents, with public persuasiveness, “presidential greatness,” and even winning the popular vote. On the other hand, excessive narcissism and bombastic ego‐reinforcement behavior are usually slandered in the public arena; there is indeed some evidence that voters evaluate negatively candidates who display excessive levels of “overt positive self‐description” (Schütz 1998 ). Once in office, a narcissist can see his “reality‐testing capacities diminish. Fantasies held in check when his power is limited are apt to become his guides to action […], his behavior becomes more erratic, he runs into difficulties in meeting his goals, and his paranoid defenses become more exaggerated” (Glad 2002 , 1). In the same vein, Watts et al. ( 2013 ) showed that grandiose narcissism is associated in U.S. presidents with a higher incidence of impeachment resolutions and unethical behavior. Individuals high in psychopathy usually show “a cognitive bias towards perceiving hostile intent from others” (Levenson 1990 , 1074) and are impulsive, are prone to callous social attitudes, and show a strong proclivity for interpersonal antagonism (Jonason 2014 ); furthermore, they should be expected to more naturally adopt a confrontational, antagonistic, and aggressive style of politics. High psychopathy reflects dominance and risk aversion (Levenson 1990 ), traits particularly rewarded in “social niches” that promote high individualism and social boldness (or “fearless dominance”; Lilienfeld et al. 2012 ). Indeed, individuals high in psychopathy have been shown to perform well in business (Babiak and Hare 2006 ) and politics (Lilienfeld et al. 2012 ). Finally, people high in Machiavellianism are usually seen as prioritizing strategic behavior, ruse, and deception to increase direct and indirect benefits. Individuals high in this trait have been shown to be wary of actions that might harm their reputation and thus act strategically to preserve a good image (Jones and Paulhus 2014 ). Machiavellian individuals are “cynical, unprincipled, believe in interpersonal manipulation as the key for life success, and behave accordingly” (Furnham, Richards, and Paulhus 2013 , 201). Evidence suggests that Machiavellians might easily suffer from a tarnished image (Ricks and Fraedrich 1999 , 204) and can be judged as having lower integrity and trustworthiness (Silvester, Wyatt, and Randall 2014 ).

Increasing evidence exists that the personality reputation of public figures can be gauged by external observers in terms of known dimensions of human personality (Caprara, Barbaranelli, and Zimbardo 2002 ; Rubenzer and Faschingbauer 2004 ; Caprara et al. 2007 ; Gallagher and Blackstone 2015 ; Visser, Book, and Volk 2017 ). Two of the most widely used inventories of personality traits are the Big Five (Goldberg 1990 ; Gerber et al. 2011 ) and the Dark Triad (Paulhus and Williams 2002 ; Jones and Paulhus 2014 ). Starting with the Big Five, people high in extraversion (or perceived to be high on this trait) show a tendency to enjoy a sociable and active life and to move away from withdrawal, passivity, and shyness (Mondak and Halperin 2008 ) and are often described as sociable, energetic, active, and assertive. Extraversion is a strong and consistent factor determining charismatic leadership (Bono and Judge 2004 ), which in turn drives electoral success (House, Spangler, and Woycke 1991 ); the retrospective analysis by Rubenzer, Faschingbauer, and Ones ( 2000 ) shows that former U.S. presidents score quite high, comparatively, in this trait. Individuals high in agreeablenes s are usually described as warm and sympathetic and can be expected to benefit from “enhance[d] marketability perceptions” (Wille, De Fruyt, and Feys 2013 , 130). Conscientious people have a tendency to plan and organize all aspects of the individual and collective life and are often associated with responsibility, conformity, achievement orientation, and dependability (Judge et al. 1999 ; Seibert and Kraimer 2001 ). Unsurprisingly, this trait appears as the highest among U.S. presidents in the retrospective analysis by Rubenzer, Faschingbauer, and Ones ( 2000 ). Quite different are individuals low on emotional stability (or high on neuroticism), who are seen as being easily subject to negative feelings such as anxiety, sadness, tension, edginess, excitability, stress, and instability and as “view[ing] many developments as unfair and often unsatisfactory” (Mondak and Halperin 2008 , 345). Finally, people high on openness show a tendency to experience fresh situations and an eagerness toward everything that is new, challenging, and stimulating. High openness to experience (vs. closed‐mindedness) is associated “with increased creativity, curiosity, imagination and nonconformity” (Mondak and Halperin 2008 , 342).

The rest of the article unfolds as follows: The next section introduces the data set we use to systematically compare the personality reputation of Trump and other (populist and nonpopulist) contemporary candidates. We provide special attention to the measures of (perceived) personality traits and discuss their validity and reliability; we also introduce the variables we use to measure the campaigning style of candidates (negativity and emotionality). The following section presents the empirical evidence, first by developing the full reputation profile of Trump according to the eight main traits, then by comparing his profile with the (average) profile of other populist candidates who are usually also portrayed as outsiders with a peculiar and disruptive political style, and finally by assessing to what extent personality matters for electoral campaigning. The last section concludes and develops several informed predictions for the trajectory of the Trump presidency based on his profile and what happened during the first years in office.

After comparing the profiles of those candidates, we assess the extent to which personality matters when it comes to campaigning strategies. We focus here on two dimensions of modern electoral communication: negativity (i.e., the use of messages intended to attack the rivals instead of promoting one’s own profile and agenda; Lau and Pomper 2004 ; Nai and Walter 2015 ) and emotionality (i.e., the use of messages intended to stir an emotional response in the audience; Brader 2006 ). The use of these two sets of communication strategies in contemporary campaigns has been documented extensively, and strong reasons exist to expect that their use matters. On the one hand, if the electoral effectiveness of negative campaigning techniques is still contested (Lau, Sigelman, and Rovner 2007 ), mounting evidence seems to suggest that negativity is associated with unintentional systemic effects, for instance, depressed turnout and mobilization (Ansolabehere and Iyengar 1995 ) or increased cynicism, apathy, and a gloomier public mood (Yoon, Pinkleton, and Ko 2005 ). On the other hand, the use of emotional elements in campaigning (Brader 2006 ; Ridout and Searles 2011 ) starts from the assumption that feelings and emotions act as powerful determinants of attitudinal behavior (Marcus and MacKuen 1993 ; Marcus, Neuman, and MacKuen 2000 ): anxious citizens are likely to pay more attention to information and campaigns, which makes them easier targets for persuasion (Nai, Schemeil, and Marie 2017 ); enthusiastic citizens are more likely to get invested and participate (Marcus and MacKuen, 1993 ), but they do so by relying strongly on their previously held partisan beliefs and attitudes (Marcus, Neuman, and MacKuen 2000 ).

The aim of this article is threefold: (1) to provide systematic evidence about Trump’s personality style, described in terms of both the five socially benevolent traits (Big Five) and the three socially malevolent traits (Dark Triad); (2) to test the assumption that Trump is unique in his extreme personality not only when compared to other contemporary political candidates but also when compared to other populist candidates who often make the headlines for their provocative political style and brashness (e.g., the Netherlands’ Geert Wilders, the Czech Republic’s Andrej Babiš, France’s Marine Le Pen, and Germany’s Alexander Gauland); and (3) to discuss the implications of Trump’s extreme personality in terms of his adoption of a harsher and more negative campaigning style—a style that defined the 2016 electoral race and can potentially move the bar of what is a “normally acceptable” rhetoric during election campaigns. We pursue these aims by comparing Trump’s perceived personality with the profile of 103 other candidates (including 21 populists) who competed in elections across the world from June 2016 to October 2017. We rely on novel data gathered through expert ratings covering key elections such as the recent contests in the United States, France, the United Kingdom, Germany, Russia, the Netherlands, Spain, Austria, Australia, and beyond (Nai and Maier 2018 ; Nai 2018a ). 4 For Donald Trump, 60 national and international scholars provided ratings of his personality, which we use to assess his public profile in terms of the Big Five and Dark Triad.

Measuring the Personality Reputation of Candidates: Data and Method

Personality is a multifaceted concept, and its measure is often an elusive matter. Even more so are the definition and measure of the personality of political figures. What do we mean by that? And how can this be measured in a systematic and reliable way? It is important to stress from the outset that we do not claim to measure the candidates’ actual psychological profile—and, even less, the clinical components of their psyche—but rather their perceived personality (reputation), that is, the way their public persona and style can be classified according to known dimensions of human personality. Like other scholars before us (Rubenzer, Faschingbauer, and Ones 2000; Rubenzer and Faschingbauer 2004; Lilienfeld et al. 2012; Gallagher and Blackstone 2015; Visser, Book, and Volk 2017), we did so by asking experts to evaluate candidates through systematic instruments that have been developed for the assessment of individual personality profiles. In this article, we describe the candidates’ personality reputation in terms of both socially desirable (Big Five) and socially malevolent traits (Dark Triad).

The Data Set To measure candidates’ personality reputations, we used a new comparative data set about electoral campaign strategies in elections worldwide (NEGex; Nai 2018a; Nai and Maier 2018),5 covering national elections held across the world from June 2016 to October 2017. We gathered the information through a systematic survey distributed to election‐specific samples of national and international scholars in elections in the weeks following each election. The survey asked scholars to evaluate the personality reputation of selected candidates via two sets of batteries used to measure both socially desirable and malevolent personality traits: one to measure the Big Five and another to measure the Dark Triad. For each battery, each expert had to evaluate only one candidate (e.g., Big Five for Trump and Dark Triad for Hillary Clinton). This procedure minimized learning effects and ensured that candidates were evaluated at face value and not by rationalizing the differences between them. Individual scholar ratings were then aggregated at the candidate level to provide systematic measures of perceived personality that are comparable across candidates. Comparing expert judgments on political dynamics over extended periods of time is potentially hazardous, as the understanding, value, and weight of core political considerations may change over time. The fact that our study was carried out over a relatively brief period of time (15 months) should normally ensure that not many of those intervening factors exist. In the absence of large‐scale comparative mass surveys and the near impossibility of having self‐rating (but see Dietrich et al. 2012; Joly, Soroka, and Loewen 2018), the personality of political figures is frequently deduced from textual secondary data (e.g., by content‐analyzing speeches; e.g., Winter 1987). However, this approach suffers from at least three shortcomings. First, textual secondary data are usually extremely controlled and crafted and thus are likely to only indirectly represent the speaker’s personality. Second, content analysis of textual archives requires extensive resources, although automated and machine‐learning approaches show very promising results (Ramey, Klingler, and Hollibaugh2016, 2017). Third, and perhaps more importantly, content analysis of political texts suffers from questionable cross‐cultural comparability, as the discursive nature of political texts is often a function of the language and political culture (Reisigl 2008). As an alternative approach, much research has relied in recent decades on the ratings of external expert observers to draw a psychological profile of political figures (Rubenzer, Faschingbauer, and Ones 2000; Rubenzer and Faschingbauer 2004; Lilienfeld et al. 2012; Gallagher and Blackstone 2015; Visser, Book, and Volk 2017; Nai and Maier 2018; Nai 2018a). Expert judgments are an efficient, yet reliable, approach to provide systematic information about how the reputation of candidates is perceived. Data can be gathered in a fast and cost‐effective way, and interviewing scholars with proven expertise increases the chances that the main concepts tapped are understood in a similar fashion—thus reducing the risk of cross‐cultural biases in comparison. Furthermore, relying on scholars allows us to dramatically expand the coverage of the data (e.g., in our case, 47 elections in 40 different countries). Issues such as linguistic expertise or knowledge of cultural dynamics are outsourced to the experts themselves, which ensures that virtually all contexts can be studied, providing that relevant experts are identified and that their collaboration can be secured. Finally, the quality of expert judgments can be assessed empirically and adjusted, for instance, to take into account each expert’s familiarity with the topic studied, which increases the reliability of the aggregated scores. We discuss below why we claim that our measures of candidates’ reputations are empirically reliable and theoretically valid—including preliminary evidence that shows that experts perceive candidates similarly to the public at large, thus suggesting that the trends described here can be translated into the general population. Considering only candidates for whom at least two6 different experts provided independent evaluations, our data set comprised 104 candidates in total (including Trump) who competed in 47 elections worldwide. Information is based on answers provided by 875 experts, aggregated at the candidate level. Appendix A online lists all the elections and candidates in our data set and specifies the number of independent expert opinions gathered for each candidate. The NEGex survey is aligned with the most well‐known and developed expert surveys in terms of methodology, coverage, and respondents’ numbers, such as the Chapel Hill Expert Survey (Bakker et al. 2015), which provides information about the positioning of political parties on political ideology since the 1990s; its most extensive wave (2014) gathered responses from 337 political scientists in Europe. NEGex expands both the number of respondents (875 in our data set) as well as the geographical scope of the analysis, which includes in our case countries from around the world. Furthermore, the NEGex questionnaire efficiently complements and expands other studies on candidates’ personality traits based on expert assessments, such as the one discussed in Visser, Book, and Volk (2017) in which the two U.S. candidates were compared.

The Experts We define an expert as a scholar with expertise in electoral politics, political communication (including political journalism), and/or electoral behavior, or related disciplines, for the country where the election was held. Expertise is established by the presence of one of the following criteria: (1) existing relevant academic publications (including conference papers); (2) holding a chair in those disciplines in a department within the country; (3) membership in a relevant research group, professional network, or organized section of such a group; or (4) explicit self‐assessed expertise included on a professional webpage (e.g., bio on university webpage). The number of experts contacted for each election varied, depending on the specific case studied, from a minimum of 28 (Nicaragua) to a maximum of 626 (United States); the average response rate was approximately 20% (Table D2 in the online appendix presents the response rate for each election‐related sample). Experts were contacted via a personalized e‐mail during the week following the election and sent two reminders, respectively, one and two weeks after the first invitation. The invitation e‐mail contained the link to the questionnaire, administered through Qualtrics. On average, experts in the whole sample lean slightly to the left (M = 4.32/10, SD = 1.79), 74% are domestic (i.e., work in the country for which they were asked to evaluate the election), and 33% are female. Overall, experts declared themselves very familiar with the elections (M = 7.95/10, SD = 1.82) and estimated that the questions in the survey were relatively easy to answer (M = 6.46/10, SD = 2.42). For the U.S. experts, who were asked to evaluate the personality and campaigning style of the candidates in the 2016 presidential election only, 81% of the sample comprises domestic experts (i.e., about 20% of the experts live and work outside the United States) and 29% are female. The level of familiarity is even higher than the overall sample (M = 8.97/10, SD = 1.11), and experts found the questionnaire quite easy (M = 7.44/10, SD = 1.96). Finally, experts in the U.S. sample are also slightly skewed toward the left (M = 3.60/10, SD = 1.58). Table D2 in the online appendix presents the composition of the sample of experts for each election surveyed. The profile of experts can, potentially, alter their assessments (Steenbergen and Marks 2007; Curini 2010; Martínez i Coma and Van Ham 2015). To assess the extent of these profile effects, we ran a series of models in which the experts’ evaluations (i.e., how they evaluate the personality profiles of the candidates) is regressed on their profile. We ran two series of models; the first series of models (Tables D3 and D4 in the online appendix) assesses the effect of experts’ profile on their evaluation of candidates for all experts in our data set, that is, regardless of the election and/or candidate evaluated: results show that expert ratings are very rarely driven by their profile, and even when a significant effect is shown, its magnitude is extremely marginal (this is, for instance, the case for the effect of familiarity on conscientiousness). The second series of models zooms in on the experts who evaluated Trump, looking for the presence of biases due to their profile (Tables D5 and D6); in this case as well, the existence of profile effects is extremely limited—with the exclusion perhaps of narcissism: experts on the left, experts self‐reportedly more familiar, and international experts evaluated Trump more harshly than their counterparts (the last effect is perhaps due to a differential coverage of Trump in international media). This being said, the extent of the bias at the sample level is questionable: given the composition of our sample for the U.S. election, the positive negative effect of left‐wing ideology in the sample should be compensated for by the fact that 80% of the experts are domestic (and thus more likely to have lower scores for narcissism). Nonetheless, caution should be exercised when interpreting results concerning Trump’s narcissism.

Measures of Perceived Personality We describe the personality reputation of candidates in terms of (1) five socially benevolent traits that form the Big Five inventory (extraversion, agreeableness, conscientiousness, emotional stability, and openness) and (2) three socially malevolent traits that form the Dark Triad inventory (narcissism, psychopathy, and Machiavellianism). The five socially benevolent personality traits (Big Five), as perceived by experts, are measured via the Ten Item Personality Inventory (TIPI; Gosling et al. 2003). For each trait, experts had to evaluate two statements (e.g., the candidate might be someone who is “critical, quarrelsome”), and the underlying personality trait exists as the average value for those statements. Compared to other measures, the TIPI is relatively short and thus less nuanced; however, it has been shown to provide satisfactory results in terms of convergent validity (Ehrhart et al. 2009; but see Bakker and Lelkes 2018). The battery of questions yields five variables ranging from 0 (very low) to 4 (very high). The measure of the three malevolent personality traits is usually done through lengthy batteries of questions such as the 40‐item Narcissistic Personality Inventory, the 20‐item MACH‐IV test for Machiavellianism, or the 31‐item Self‐Report Psychopathy III scale (Paulhus and Williams 2002). For pragmatic reasons, we designed a shorter version of the Jonason and Webster (2010) Dirty Dozen battery based on the principal component analyses described in their study (422); we selected the two items that correlate the highest with each trait and used them as a battery (see the Supporting Information online).7 As for the Big Five, the Dark Triad variables we obtained from this battery range from 0 (very low) to 4 (very high). Appendix B online provides more details about the measures of personality reputation.

Validity and Reliability If we look at the personality reputation measures across all candidates in our data set (N = 104), we first observe that the internal validity of the eight traits, assessed through reliability checks, is high,8 and so is construct consistency (Tables B1 and B2). Comparing the two sets of traits, the relationship between the Big Five and Dark Triad traits has been shown to be sometimes erratic (e.g., Lee and Ashton 2005), but several similar patterns are often reported—for instance, agreeableness has been shown to correlate negatively with all three Dark Triad traits, conscientiousness is negatively associated with psychopathy and Machiavellianism, and narcissism is positively associated with extraversion (Paulhus and Williams 2002). We find all those patterns in our data as well (Table B3). A big question, of course, is whether our measures are able to effectively reflect the reputation and public personas of the candidates. This issue, external validity, is harder to assess than empirical reliability due to the absence of comparable data about the personality reputation, character, or public personas of candidates competing in elections worldwide. However, we discuss here three pieces of information that suggest, individually and jointly, that our measures seem to reflect shared views on the reputation of the candidates. First, we collected information about the public personas, character, and personality for 53 candidates as described independently in news media reports and scientific publications (see Table B5 in Appendix B online). For each candidate, we conducted an online search of news articles about him or her that refer in the title or body to the terms “personality,” “style,” “reputation,” “character,” and “profile.”9 All relevant articles (i.e., describing the personality of candidates along traits echoing the Big Five or Dark Triad—for instance, “charismatic,” “boring,” “narcissistic,” “reserved”) were reported in the table and used for comparison with our measures. Very often the image of those candidates as portrayed in the media and beyond converges closely with the measure of personality reputation we obtained from our experts through standardized questions. For instance, Angela Merkel is described in the media as uncharismatic, “reserved, rational and uninspiring” (Hung 2012), and having a public speaking style “as inspiring as the Eurozone quarterly growth figures” (Butler 2013) (we found in our data very low extraversion, but very strong conscientiousness and emotional stability); Theresa May is qualified as overall lacking personality and having “all the warmth of a wet weekend in Whitstable” (Mcleod 2017) and “the emotional intelligence of the Terminator” (Kurd 2017) (we found very low extraversion and agreeableness and high psychopathy); Norbert Hofer is described as “a wolf in sheep’s clothing […that learned] how to play nice” (MacKinnon 2017) (we found high Machiavellianism); Geert Wilders is accused of having “a controversial attitude and aberrant political style” (De Landsheer and Kalkhoven 2014) and “not trying at all to be agreeable” (McBride 2017) (we found very low agreeableness); and Emmanuel Macron is described as being “quite charismatic and [… leading a party with] a whiff of a personality cult” (Miller 2017) and as a “master of seduction” (Heyer 2017), but also as “politically savvy” (Miller 2017) (we found high narcissism and high conscientiousness). Of course, this does not represent a systematic test of external validity. The information was only available for a subsample of candidates (53 out of 104), and although chosen following a systematic protocol, the media analyzed are not necessarily representative of all articles published about those candidates from a statistical standpoint. Nonetheless, the consistent overlap we found between the content of the articles retrieved and our measures suggests that our data are efficient in capturing the major reputation traits of those candidates. Second, our scores for Hillary Clinton and Donald Trump overlap very strongly with trends described in a recent study by Visser, Book, and Volk (2017) that relies on ratings from a sample of experts having published on the psychology of personality. Their measures are extremely similar to the scores that both Clinton and Trump received from our experts (for more details, see Nai and Maier 2018). Third, we asked undergraduate students at the University of Amsterdam (Netherlands)10 to evaluate four candidates using the same batteries as presented above: in the first study, 275 students evaluated the personality of Donald Trump, and in the second study, 200 students evaluated the personality of two main Dutch political figures, the current Prime Minister Mark Rutte and the populist leader of the Partij voor de Vrijheid (Party for Freedom) Geert Wilders, and the personality of Angela Merkel. Comparing the two sets of evaluations shows strong consistency. Some small differences between the two populations exist—for instance, the experts tended to see Trump as slightly less agreeable than the students, whereas the students on average saw Wilders as more Machiavellian, Rutte as less agreeable, and Merkel as more extraverted than the experts did. Nonetheless, the scores obtained by those candidates in the expert and student data sets are very strongly correlated (Trump, R = 0.97; Rutte, R = 0.76; Wilders, R = 0.85; Merkel, R = 0.89; see Table B4 in Appendix B online). This suggests that the two populations perceive the different candidates in a very similar way overall even across cultures, which we see as an additional confirmation of the external validity of our measures.

Campaigning Style We measure the content of electoral campaigns—negativity and emotionality—also via aggregated expert judgments (Nai 2018b). Experts evaluated the tone of candidates’ campaign on a scale ranging from −10 (the campaign was exclusively negative) to 10 (the campaign was exclusively positive) and were also asked to evaluate the type of attack candidates mostly used against their rivals on a scale ranging from 1 (exclusively policy attacks) to 5 (exclusively character attacks). Finally, the experts were asked to assess the extent to which candidates used anxiety and enthusiasm appeals, using a scale ranging from 0 (very low use) to 10 (very high use). These four variables, aggregated at the candidates’ level, have been standardized to fit into a 0–1 scale to allow comparison and simplify their interpretation in regressions.