Suppose politician C goes negative on politician M. Politician’s M’s support declines..where do his supporters go? If there are just two candidates, they either go to politician C or stay at home. But if there are three or more candidates, they might go to politician A, B, or K etc etc. So, to a first order, it is less profitable to go negative the greater the number of candidates.
This resembles the Holmstrom teams model but with unproductive effort.
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February 10, 2016 at 7:21 pm
Enrique Guerra-Pujol
Great question, but why assume a static environment? Once candidate C goes negative, an arms race usually ensues in which M goes negative too! Also, I suspect many voters actually enjoy negative ads …
February 13, 2016 at 8:44 am
Sandeep Baliga
Feel free to work out the static or dynamic version! Just acknowledge me in footnote.
February 14, 2016 at 6:07 pm
Enrique
or better yet, let’s write it together: you do the static part of the model and I’ll do the dynamic one
February 28, 2016 at 6:19 pm
Sourav
There is a paper in JLEO by Amit Gandhi and co-authors testing this empirically, They do find that incidence of negative campaigning falls with the number of candidates in competition.