Click on the picture if you wish to read about the “Mars effect”
A) You want to test the theory that people who were born close to noon on July 7 are unusually tall. You choose randomly 100 Norwegian men over 25 years old and discover that the one person born closest to noon of 7/7 is the 15th tallest among them. Then you chose 100 Nigerian women and discover that the woman born closest to noon on July 7 is the 10th tallest. You figure out that without the putative effect being real (in other words, under the null hypothesis) the chance for such results occuring at random is 1/10 times 3/20 which is 1.5%, and conclude that this lends significant support to your theory. Are you correct?
B) In a certain scientific area, the level of significance required for a statistical test is 5%. Would it serve the quality of scientific papers in this area to reduce the required significance level to, say, 0.5%, in order to exclude publishing papers which report experiments that were successful by sheer chance?