"In investigating the question of whether men are smarter than women, British researcher Adrian Furnham came up with some startling results. His analysis of some 30 studies showed that men and women are fairly equal overall in terms of IQ, but women underestimate their own intelligence while men overestimate theirs. Surprisingly, both men and women perceived men being smarter across generations — both sexes believe that their fathers are smarter than their mothers and their grandfathers are more intelligent than their grandmothers. And if there are children, both men and women think their sons are brighter than their daughters."

Source:http://science.slashdot.org/story/09/12/06/2228210/How-Men-and-Women-Badly-Estimate-Their-Own-Intelligence