part of statistical hypothesis test objective null hypothesis A null hypothesis is a statistical hypothesis that is tested for possible rejection under the assumption that it is true (usually that observations are the result of chance). The concept was introduced by R. A. Fisher. The hypothesis contrary to the null hypothesis, usually that the observations are the result of a real effect, is known as the alternative hypothesis.[wolfram alpha] Alejandra Gonzalez-Beltran Orlaith Burke Philippe Rocca-Serra http://mathworld.wolfram.com/NullHypothesis.html hypothesis alternative hypothesis ready for release