HAL Id: hal-01875313
https://hal.archives-ouvertes.fr/hal-01875313 Submitted on 17 Sep 2018
HAL is a multi-disciplinary open access
archive for the deposit and dissemination of sci-entific research documents, whether they are pub-lished or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers.
L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.
Fluctuations of the desirability bias of voters during the 2017 French presidential elections
Aurélie Mouneyrac, Tania Wittwer, Céline Lemercier, Valérie Le Floch
To cite this version:
Experiment A: Inter-subject design
Specific manipulation: Varying the time available between the vote and the completion of the survey
209 participants answered an online survey (Mage = 35.6,
SDage = 1.1). Only data of respondents for 9 candidates (out
of 11) were kept others were n < 5.
Overestimation bias: Estimation of the election result of the preferred candidate (on a scale from 0 to 100%) is compared to his/her election result (collected after the elections).
Time available: the delay between the completion of the survey and the respondents’ vote.
Results:
H1: Respondents overestimate the election result of their preferred candidate.
Note. t test were significant at p < .01 except for voters of E. Macron, P. Poutou and M. Le Pen.
H2: Contrary to our expectation, results show significantly negative correlation between time available and the overestimation bias (r = -.171, p = .013) meaning that the overestimation bias decreases over time.
Experiment B: Mixed design
Specific manipulation: Varying the degree of reflection about politics
92 participants answered 3 online surveys during the
election day (Mage = 30.7, SDage = 1.5). Only data of
respondents for 3 candidates were kept as others were n < 5.
Content varies among 3 conditions (inter-subject design):
- Reflection : quotes about politics to rate (from sad to happy)
- Distraction : jokes to rate (from sad to happy)
- Neutral : no content to rate
Overestimation bias is a repeated measure.
Results:
H1: Respondents overestimate the election result of their preferred candidate.
Note. t test were significant at p < .01 except for voters of E. Macron.
H2: The overestimation at 10 a.m. does not increase over time (Pillai’s Trace: V < 1, ns). The reflection condition (pertaining to distraction and neutral conditions) does not increase the overestimation bias (F < 1, ns), even in interaction with time of questionnaire completion (V < 1, ns).
Aims
1/ Replicating the overestimation bias in real
presidential elections.
H1 : Voters overestimate their preferred candidate’s election result as compared to the election result obtained
2/ Identifying illusory control
H2 : The respondents who have the longest time to reflect on the reasons why their preferred candidate would win will be more likely to overestimate their preferred candidate’s election result – thus showing illusory control.
Two experiments were conducted on April 23rd, 2017.
Background
Desirability bias is an overestimation of the
probability of occurrence of a preferred
outcome, while underestimating the occurrence of unwanted outcomes.
Conclusion
On the election day, voters tend to overestimate the election result of their preferred candidate. However, contrary to the expectations, this bias does not increase over time after the vote. Among the factors that might explain this are the processes involved during the weeks and months before the election day, rather than during the hours just after the vote. Confidence in the preferred candidate’s election result might increase until it reaches a level important enough to encourage the voter to vote for the candidate on the election day – reaching a ceiling effect after the vote. As the overestimation bias over the election day has a robust effect, it might be a process influencing people to vote – even if their vote has proportionally a very low impact on the result of the election.
Content + estimation 10:00 a.m. Content only 3:00 p.m. Content + estimation 6:00 p.m.
Companion study presented in this congress:
Causal Attributions in a French Electoral Context (Wittwer, T., Mouneyrac, A., Py, J. & Tredoux, C.)
Voters are prone to the desirability bias: they overestimate their preferred candidate’s chances of winning (Granberg & Brent, 1983).
Illusory control is also an overestimation of the
chances of winning. However, this bias is explained by the perceived control individuals have on their environment. This bias has been extensively studied in gambling (e.g. sports betting).
In particular, the more gamblers think about an event, the more they are willing to believe its occurrence. Time available between the bet and the result is thus a factor that increases illusory control (Langer, 1975). For the first time, we examined voters’ illusory control in real presidential elections.
Aurélie Mouneyrac, Tania Wittwer, Céline Lemercier & Valérie Le Floch
University of Toulouse, CLLE aurelie.mouneyrac@univ-tlse2.fr 0 5 10 15 20 25 30 35 Electio n r esult (%)
Candidates’ election results: mean of estimations versus real election result
Estimation
Real score
References:
Granberg, D., & Brent, E. (1983). When prophecy bends: The preference–expectation link in US presidential elections, 1952–1980. Journal of Personality and Social
Psychology, 45(3), 477-491.
Langer, E. J. (1975). The illusion of control. Journal of personality and social psychology,
32(2), 311-328. 0 5 10 15 20 25 30
J.L. Mélenchon E. Macron B. Hamon
Electio
n
r
esult
(%)
Candidates’ election results: mean of 10 a.m. and 6 p.m. estimations versus real election result
Estimation at 10 a.m. Estimation at 6 p.m. Real score
