If the frequencies within one, two and three standard deviations of the average are known (34,1%, 13,6% and 2,1%), can one calculate the frequency from a certain value?

 

More specifically, I want to know if, if it is true that Ashkanazi Jews are 10% more intelligent, how much percent is gifted. Normally, that's 2,1%. If the average IQ in Ashkenazis really is 110, then the Bell curve shifts 10 points and 13,6% should have an IQ from 125 to 135. Subtract the frequency of IQs from 125-130, add the other 2,1%, and you have the frequency of giftedness. How do I know the frequency of IQs from 125-130?

 

And please, no paranoid ragings about racialism here. I'm not Jewish myself and was merely curious about this hypothesis.

Assuming this sub-group has a higher mean (median?) score on IQ tests, I don't see any reason to expect the score distribution would simply be a "shifted" curve congruent with the general population's curve and measured on the same scale.

You mean the bell curve would not only shift but might also either become flatter or steeper? Hadn't thought of that.

Or it might not be a traditional bell curve at all, measured on the same scale as the general pop. But we should back up - what IQ test are you talking about?