With reference to Exercise 78, use the result of part (b) of Exercise 39 to construct a 99% confidence interval for the mean weekly net profit of restaurants with a seating capacity of 210 at a location where the daily traffic count averages 14,000 cars.
Exercise 78
The following are data on the average weekly profits (in $1,000) of five restaurants, their seating capacities, and the average daily traffic (in thousands of cars) that passes their locations:
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(a) Assuming that the regression is linear, estimate β0, β1, and β2.
(b) Use the results of part (a) to predict the average weekly net profit of a restaurant with a seating capacity of 210 at a location where the daily traffic count averages 14,000 cars
Exercise 39
If x01, x02, ... , x0k are given values of x1, x2, ... , xk and X0 is the column vector
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it can be shown that
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is a value of a random variable having the t distribution with n - k - 1 degrees of freedom.
(a) Show that for k = 1 this statistic is equivalent to the one of Exercise 23.
(b) Derive a (1 - α)100% confidence interval formula for
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Exercise 23
Use the results of Exercises 20 and 21 and the fact that
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Exercises 20
Under the assumptions of normal regression analysis, show that
(a) the least squares estimate of α in Theorem 2 can be written in the form
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(b)
has a normal distribution with
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Theorem 2
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Exercises 21
This question has been intentionally omitted for this edition.