The Binomial Test procedure compares an observed proportion of cases to the proportion expected under a binomial distribution with a specified probability parameter. The observed proportion is defined either by the number of cases having the first value of a dichotomous variable or by the number of cases at or below a given cut point on a scale variable. By default, the probability parameter for both groups is 0.5, although this may be changed. To change the probability, you enter a test proportion for the first group. The probability for the second group is equal to 1 minus the probability for the first group. Additionally, descriptive statistics and/or quartiles for the test variable may be displayed.