When estimating their intelligence, men boast while women are more modest, according to a study. Adrian Furnham, professor of psychology at University College London, investigated the self-rated intelligence levels of 2,006 people in 12 countries. He found the largest gender difference in France, where men on average rated their intelligence 15 IQ points higher than women did. The second-largest difference was in the British sample, with men rating their intelligence on average 10 IQ points higher. The research was published in the British Journal of Psychology.