Transportation Statistics and Microsimulation

Sampling Distributions    ◾    101

population distribution (as long as the variance exists). e population dis-

tribution may be discrete or continuous, as well as symmetric or skewed.

Nevertheless, we can make inferences about the mean of the population

without depending on its distribution, and this is why the CLT is oen con-

sidered the most important theorem in statistics. You will see variations of

the above equations throughout the remainder of the text whenever infer-

ences on population means are required.

e central limit theorem on the sample mean can be illustrated using

the SA loop speed data (recorded in mph) given in Figure 3.1.