I do an informal experiment testing whether LessWrong karma scores are susceptible to a form of anchoring based on the first comment posted; a medium-large effect size is found although the data does not fit the assumed normal distribution & the more sophisticated analysis is equivocal, so there may or may not be an anchoring effect.
Have I? If I have, I'm sure there were some germane difference: banned accounts, more than 1 sock, abuse of socks to gain multiple votes, unsystematic data collection, no analysis, no public claim, clear damage, etc.
Full writeup on gwern.net at http://www.gwern.net/Anchoring