1 Suppose we are interested in the relationship between the

1. Suppose we are interested in the relationship between the glucose concentration y (in g/L) and the fermentation time x (in days) for a particular blend of malt liquor. The glucose concentration was measured over n = 8 days and the following polynomial regression results of the data were reported.

yˆ = 84.482115.8750x +1.7679x 2 SSResid = 61.7679 SSTotal = 586.8750

a. Estimate the mean glucose concentration for malt liquor that has fermented for x = 9 days.

b. Give a point estimate for the standard deviation of (i.e., a point estimate for e ).

c. Compute and interpret the value of R2 , the coefficient of multiple determination.

Solution

a)

Y = 84.4821 - 15.8750 * 9 + 1.7679 * (9)^2

Y = 84.807

b)

SD = 586.8750 / 61.7679 = 9.5013

c)

R ^2 = 1 - 61.7679 / 586.8750 = 0.89475