Outcomes: conduct a test of hypothesis for two independent population means. Use separate-variance t test when unequal s are known s and s are unknown and s are unknown but equal s and. Characteristics of f distribution: there is a family of f distributions. Each member of the family is determined by two parameters i. the degree of freedom in the numerator ii. the degree of freedom in the denominator: the f distribution is continuous. This means that it can assume an infinite number of values between 0 and positive infinity: the f distribution cannot be negative. The smallest value f can assume is 0: it is positively skewed. The long tail of the distribution is to the right-hand side. As the number of degrees of freedom increases in both numerator and denominator, the distribution approaches a normal distribution: it is asymptotic. Ryerson limos offers limousine service from the city hall in toronto, ontario, to the.