Cava de' Tirreni 2015
The field experiment took place during the 2015 electoral race for mayor in Cava de' Tirreni -- a mid-size city in the South of Italy, which featured the incumbent facing two main challengers. The treatment consisted of canvassing done by volunteers of one of the challengers either with a positive message or with a negative message against the incumbent. The randomization took place at the precinct level (link to picture): a third of the 55 precincts were canvassed by the volunteers with a positive message, a third with a negative message, and the remaining third received no informational treatment. We study the e ffect of these treatments on actual electoral outcomes: the vote shares obtained by the three candidates and the turnout rate at the precinct level in the first round of the election.
Positive Spillovers from Negative Campaigning, with Tommaso Nannicini and Salvatori Nunnari, American Journal of Political Science, 2021. Online Appendix, Replication Data.
Negative advertising is frequent in electoral campaigns, despite its ambiguous effectiveness: Negativity may reduce voters’ evaluation of the targeted politician but may have a backlash effect for the attacker. We study the effect of negative advertising in electoral races with more than two candidates with a large-scale field experiment during an electoral campaign for mayor in Italy and a survey experiment in a fictitious mayoral campaign. In our field experiment, we find a strong, positive spillover effect on the third main candidate (neither the target nor the attacker). This effect is confirmed in our survey experiment, which creates a controlled environment with no ideological components or strategic voting. The negative ad has no impact on the targeted incumbent, has a sizable backlash effect on the attacker, and largely benefits the idle candidate. The attacker is perceived as less cooperative, less likely to lead a successful government, and more ideologically extreme.
Treatments: Positive & Negative Electoral Campaign -- Canvassing
Positive campaign material.
Negative campaign material.
Randomization at Precint Level