Statistics and Probability with Applications for Engineers and Scientists, Preliminary Edition

Chapter 8

Estimation of Population Parameters

The focus of this chapter is the development of methods for finding point and interval estimates of population parameters. The topics covered are:

• Point estimators for the population mean and variance
• Interval estimators for the mean of a normal population
• Interval estimators for the difference of means of two normal populations
• Interval estimators for the variance of a normal population
• Interval estimators for the ratio of variances of two normal populations
• Other estimation methods: method of moments and the method of maximum likelihood
• Point and interval estimators for the binomial parameter
• Prediction: estimation of a future observation

Learning Outcomes

After studying this chapter, the reader will be able to

• Understand the role of estimation in applied statistics.
• Determine the point and interval estimates for parameters of various discrete and continuous distributions.
• Understand the concept of a confidence coefficient and interpret confidence intervals.
• Understand the distinction between statistical and practical significance.
• Apply statistical packages MINITAB, Microsoft Excel and JMP to determine confidence intervals of parameters of various distributions.

8.1 Introduction

We often encounter statistical problems of the following type: we have a large lot or population of objects such that, if a measurement were made on each object, we would have a distribution of these measurements. Since these measurements have not been ...