An engineer wants to fit the model η = βx to the following data by the method of least squares. The tests were made in the random order indicated below. Do this work for him. First make a plot of the data.
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(a) Obtain the least squares estimate for the parameter β.
(b) Find the variance of this estimate (assuming that the variances of the individual y readings are constant and equal to 16).
(c) Obtain a 90% confidence interval for β.
(d) Make any further analysis you think appropriate and comment on your results. State any assumptions you make.