http://www.pnas.org/cgi/content/abstract/0504902103v1

Is a link to the abstract of this article from the Proceedings of the National Academy of Sciences:

"Stabilizing the Earth's climate is not a losing game: Supporting evidence from public goods experiments", by Manfred Milinski and others.

I will only highlight the abstract here, and say that they performed an experiment demonstrating that people will make small donations in favor of climate change after being informed on the issue. They become more generous if they are publicly known for having donated.

While the experiment appears to make no mention of hybrid vehicles, I sent an email to the lead author. Suggested that their experiment seems consistent with the idea that hybrid vehicle drivers are willing to pay "extra" for their vehicles, and even bear some perceived risk on the technology/reliability side. For the most part hybrid vehicles are readily identifiable, and some owners will go further and purchase distinctive license plates. I also requested a reprint of the article, which is "what scientists do".

I am not aware of other scientific studies that might relate to hybrid vehicle purchasing decisions. What has anyone else seen?