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Statistics and probability

Course: Statistics and probability > Unit 15

Lesson 1: Inference about slope

Introduction to inference about slope in linear regression
Conditions for inference on slope
Confidence interval for the slope of a regression line
Confidence interval for slope
Calculating t statistic for slope of regression line
Test statistic for slope
Using a P-value to make conclusions in a test about slope
Using a confidence interval to test slope
Making conclusions about slope

Confidence interval for slope

Musa is interested in the relationship between hours spent studying and caffeine consumption among students at his school. He randomly selects

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students at his school and records their caffeine intake (mg) and the amount of time spent studying in a given week. Here is computer output from a least-squares regression analysis on his sample:

Predictor	Coef	SE Coef	T	P
Constant	$2.544$ ‍	$0.134$ ‍	$18.955$ ‍	$0.000$ ‍
Caffeine	$0.164$ ‍	$0.057$ ‍	$2.862$ ‍	$0.010$ ‍
$S = 1.532$ ‍	$R-sq = 60.0 %$ ‍

Assume that all conditions for inference have been met.

Which of these is a $95 %$ ‍ confidence interval for the slope of the least squares regression line?

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Statistics and probability

Course: Statistics and probability > Unit 15

Problem