# Building a quadratic regression model

See attachment for data on y = green liquor (g/L) and x = paper machine speed (ft/min) from a Kraft paper machine.

(a) Fit the model Y = Bo + B1x + B2x^2 + e using least squares.

(b) Test for significance of regression using alpha = 0.05. What are your conclusions?

(c) Plot the residuals from the model in part (a) versus y. Does the plot reveal any inadequacies?

(d) Construct a normal probability plot of the residuals. Comment on the normality assumption.

See attachment for given chart.

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Part a:

After running quadratic regression in excel, the ...

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The solution builds a quadratic regression model and tests both significance and normality assumption of the model using excel.

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