I also believe that diversity is important, but I feel like diversity in this case isn't that important. Take for instance my earlier preference for AoE over Candy Crush. Is there a reason why I should look to create a diverse distribution of Candy Crush/AoE players in my workplace?
Similarly, what is it about this distribution in academia that gives it a particularly quantifiable effect on Republicans? Is there evidence of an effect? Why aren't we talking about third-party candidates or non-voters?
What evidence is there that a lack of diversity in political views in social psychology leads to a lack of truth in that discipline?
As to your last three paragraphs I suggest reading the journal article. If you want to continue the discussion after doing that feel free.
Perhaps I was being confusing, so I'll try again: What quantifiable evidence (not anecdotal, not hearsay, "may be" or implication) is there that this ratio of liberals to conservatives is an indicator of negative outcomes for conservatives?
I think we may be speaking at cross purposes. I care about this because ideological diversity leads to a greater diversity of viewpoints, which makes it more likely that the hypothesis will be examined from a number of viewpoints, so any flaws are more likely to be discovered. This is a social psychology result that has held up to replication.
What do you mean by negative outcomes for conservatives? I would have thought that denying one tenure for one's political opinions would be a pretty negative outcome for any academic.
There is a very large difference between 68-32 and 98-2. The first is the vote among postgrad holders in 2008, the second the liberal-conservative gap among social psychology postgrads.
I do not care about Republicans. I care about the truth. If social psychology and other academic disciplines are overwhelmingly liberal they will be less likely to approach the truth because of a lack of viewpoint diversity.