[4] Describing Relationships Between Variables

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Describing Relationships Between Variables

Stephen B. Vardeman & J. Marcus Jobe

This chapter is part of: Vardeman S. & Jobe J. 2023. Basic Engineering Data Collection and Analysis

Description
The methods of Chapter 3 are really quite simple. They require little in the way of calculations and are most obviously relevant to the analysis of a single engineering variable. This chapter provides methods that address the more complicated problem of describing relationships between variables and are computationally more demanding. The chapter begins with least squares fitting of a line to bivariate quantitative data and the assessment of the goodness of that fit. Then the line-fitting ideas are generalized to the fitting of curves to bivariate data and surfaces to multivariate quantitative data. The next topic is the summarization of data from full factorial studies in terms of so-called factorial effects. Next, the notion of data transformations is discussed. Finally, the chapter closes with a short transitional section that argues that further progress in statistics requires some familiarity with the subject of probability.

Description

The methods of Chapter 3 are really quite simple. They require little in the way of calculations and are most obviously relevant to the analysis of a single engineering variable. This chapter provides methods that address the more complicated problem of describing relationships between variables and are computationally more demanding. The chapter begins with least squares fitting of a line to bivariate quantitative data and the assessment of the goodness of that fit. Then the line-fitting ideas are generalized to the fitting of curves to bivariate data and surfaces to multivariate quantitative data. The next topic is the summarization of data from full factorial studies in terms of so-called factorial effects. Next, the notion of data transformations is discussed. Finally, the chapter closes with a short transitional section that argues that further progress in statistics requires some familiarity with the subject of probability.

Details

Published	Published By	Pages
Jan. 12, 2023	Iowa State University Digital Press	98
License Information
© 2001 Stephen B. Vardeman and J. Marcus Jobe. Basic Engineering Data Collection and Analysis is available under a Creative Commons Attribution NonCommercial ShareAlike (CC BY-NC-SA) 4.0 International license. You may share and adapt the material, so long as you provide appropriate credit to the original authors, do not use the material for commercial purposes, and any adaptations or remixes of the material which you create are distributed under the same license as the original.
Citation
Vardeman S. & Jobe J. 2023. Describing Relationships Between Variables. In Vardeman S. & Jobe J. 2023. Basic Engineering Data Collection and Analysis