Are YOU more intelligent than the average person?
Of course! :-)
The survey also revealed that race was not a major contributor to these thoughts ...
I know what you mean, but ... "race"? Apart from the area of selective breeding I would say normally the term 'subspecies' is used instead of 'race', and apart from that, nowadays taxonomists abstain from dividing the species Homo sapiens into different subspecies.
Concerning the question if human 'races' do exist maybe this article is quit interesting to read.
As long as for example two randomly chosen Europeans can differ genetically more from each other than one of them differs from a randomly chosen African individual, one cannot talk of different 'races'.
Race was the term used by the authors. Certainly from a genetic perspective, there is no such thing as race. It's purely a phenotypic term, though perhaps epigenetic modifications play some role in the quantization of what people define as "races." That would certainly be something not taken into consideration in the 2006 article you provided. I don't know, it's not something I really think about, I don't care about where people are from, only how they think.
I am aware that the linked text is not the newest anymore but due to some good explanations I still prefer it over most other sources available in the internet ... the current taxonomic assessment is still the same anyway ...
Concerning the self-rating of being more intelligent than average that's just typical human. Let me name another funny example: if you ask people about the coming soccer world champion, the majority (or at least a rather high percentage) will answer their own country will probably win, even if - obviously - the probability p = 1 that any team will win the tournament is distributed on all teams, so that even the best team has a rather low probability (not more than typically roughly p = 0.2 or lower) to become world champion.
I guess educated people are a bit atypical, in rating them selves on average less intelligent then they are. :D