Comparing Means of More Than Two Samples

Abstract

In Chapter 11 we took two approaches to comparing the means of two samples. The first approach involved using each sample separately to estimate the mean of the population that the sample came from. We then attached error ranges for several confidence levels to these estimates and drew a picture of the whole thing with a bullet graph (Fig. 11.1). This approach is easily extended to the comparison of any number of samples. In this chapter we will use another fictitious example consisting of 127 Archaic period projectile points from the Cottonwood River valley. After considering possible sources of bias, we decide to work with these as a random sample from the large and vaguely defined population of Archaic projectile points from the Cottonwood River valley.