Archaeology: Cultural Affiliation “Unknown cultural affiliations and loss of identity at high elevations.”

These words are used to propose the hypothesis that archaeological sites tend to lose their identity as altitude extremes are reached. This idea is based on the notion that prehistoric people tended not to take trade wares to temporary settings and/or isolated areas (Source: Prehistoric New Mexico: Background for Survey, by D. E. Stuart and R. P. Gauthier, University of New Mexico Press). As elevation zones of prehistoric people (in what is now the state of New Mexico) increased, there seemed to be a loss of artifact identification. Consider the following information.

Elevation Zone Number of Artifacts Number Unidentified 7000–7500 ft 112 69 5000–5500 ft 140 26 Let p1 be the population proportion of unidentified archaeological artifacts at the elevation zone 700027500 feet in the given archaeological area.

Let p2 be the population proportion of unidentified archaeological artifacts at the elevation zone 500025500 feet in the given archaeological area.

(a) Check Requirements Can a normal distribution be used to approximate the pˆ pˆ 1 2 2 distribution?

Explain.

(b) Find a 99% confidence interval for p1 2p2.

(c) Interpretation Explain the meaning of the confidence interval in the context of this problem.

Does the confidence interval contain all positive numbers? all negative numbers? both positive and negative numbers? What does this tell you (at the 99% confidence level) about the comparison of the population proportion of unidentified artifacts at high elevations (700027500 feet) with the population proportion of unidentified artifacts at lower elevations (500025500 feet)? How does this relate to the stated hypothesis?

AppendixLO1