Concept explainers
Pillar stability is a most important factor to ensure safe conditions in underground mines. The authors of “Developing Coal Pillar Stability Chart Using Logistic Regression” (Intl. J. of Rock Mechanics & Mining Sci., 2013: 55–60) used a logistic regression model to predict stability. The article reported the following data on x1 = pillar height to width ratio, x2 = pillar strength to stress ratio, and stability status for 29 coal pillars.
The corresponding logistic regression output from R is given here:
a. Using the output with α = .1 to determine whether the two predictor variables appear to have a significant impact on pillar stability.
b. Provide interpretations for e2.774 and e5.668.
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Chapter 13 Solutions
Probability and Statistics for Engineering and the Sciences
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