Why Do We Support Underdogs?

That's the interesting question that Yvain has posed at Less Wrong. He points to Vandello et al's study from 2007 with empirical evidence for the claim. When participants were asked to consider a hypothetical sports competition in which one team as "highly favored to win," 81% of them preferred the underdog. Subjects were asked to rate their support (on a scale of 1-9) for teams competing in the Olympics; Sweden was the favorite, Belgium was the middle-ranked team, and Slovenia was the underdog. In individual match ups, subjects preferred Belgium to Sweden (6.4 to 4.1), Slovenia to Belgium (6.8 to 4.5), and most strongly Slovenia to Sweden (7.0 to 4.0).

Finally, the Palestinian-Israeli conflict was framed through map manipulation as either a case where the Israelis are the underdog against the greater Middle East or where the Palestinians are the underdog against the larger Israelis. When Palestine was framed as the underdog in the conflict, 53.3% were more supportive towards Palestine. When Israel was framed as the underdog, 76.7% were more supportive towards their side! So the effect size for the phenomenon is robust.

Skimming through the comments, the most plausible reasons for this tendency have been:

• Cut off in this large world from our ancestral environment, we all feel like underdogs. So when we see another underdog we see similarity which enhances feelings of sympathy.
  
• If there is a tribal conflict between two leaders and you are not currently affiliated with either, it may be optimal to support the underdog without angering the overdog. Presumably the underdog will have fewer supporters and if he wins you will reap huge rewards in terms of status and resources for having supporting him early.
  
• If you see two enemies fighting, you want them both to use up as many resources as possible, so the winner is weaker and less of threat to you. You can accomplish this by systematically supporting the weaker side.
  
• Social signaling that you are clever and independent because you can adopt a minority opinion and support it.
  
• We don't actually support underdogs (especially when it is costly), but instead signal a tendency to support the underdog, in order to look more impressive and keep any overly ambitious tribal leader in check. As a prediction of this explanation, there should be a disconnect between expressed opinions about distant situations and actual proximal responses.
  
• Empathy circuits--humans like to help and to be seen as helping, and the underdog is the party that needs more assistance.

My explanation, which I admit is a little bit weak, is based on terror management theory. By supporting a cause that is probably going to win anyway, we gain little. But by supporting an unlikely cause such as Leonidas at Thermopylae, there is an increased possibility that if we succeed our accomplishments will live on past us, because they will be so incredible. In this way, we become immortal.

One problem with this theory is essentially trivial contests such as the Olympics should not have such a large impact on our psyche, but perhaps it is difficult for our monkey brains to differentiate between actually important events and non-important ones. One prediction of my explanation is that preferences for underdogs should increase when subjects are primed to consider their own mortality.

Do you have any ideas?

Cite: Vandello JA, Goldschmied NP, Richards DA. 2007 The Appeal of the Underdog. doi: 10.1177/0146167207307488.