Concept explainers
Confidence Intervals for β0 and β1 Confidence intervals for the y-intercept β0 and slope β1, for a regression line (y = β0 + β1x) can be found by evaluating the limits in the intervals below.
where
where
The y-intercept b0 and the slope b1 are found from the sample data and tα/2 is found from Table A-3 by using n − 2 degrees of freedom. Using the 40 pairs of shoe print lengths (x) and heights (y) from Data Set 2 in Appendix B, find the 95% confidence
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Elementary Statistics
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