Concept explainers
(a)
Construct a
(b)
Find the value of
Find the value of
Find the value of b.
Find the equation of the least-squares line.
Construct the line on the scatter diagram.
(c)
Find the sample
Find the value of the coefficient of determination
Mention percentage of the variation in y is explained by the least-squares model.
(d)
Check whether the claim that the population correlation coefficient is positive or not.
(e)
Find the number of people would be predicted to buy insurances when a week during which Dorothy makes 18 visits.
(f)
Verify the values of
(g)
Find the 95% confidence interval for the number of sales Dorothy would make in a week during which made 18 visits.
(h)
Check whether the claim that the slope
(i)
Find a 80% confidence interval for
Interpret the confidence interval.
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Chapter 9 Solutions
Understandable Statistics: Concepts and Methods
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