# Regression Analysis

An analyst would like to predict water consumption in a city based on daily temperature. She has gathered the following data for a random sample of n= 7 days.

Temperature ( C) 40 5 25 15 10 30 35

Water Consumption(million gallons) 225 25 150 100 75 125 175

Using the following sums and sums of squares and cross-products

Summation of x= 160 Summation of y= 875 SS(x)= 1042.857 SS(y)= 26,250 SS(xy)= 5,000

A) Compute the regression line to explain "water consumption" in terms of "temperature".

B) Test, at the alpha= 0.01 level of significance, whether temperature is a significant predictor of water consumption.

C) Compute the coefficient of determination of the regression model.

D) Find a 99% confidence interval for water consumption on a particular day when the temperature is 28ÂºC.

https://brainmass.com/statistics/regression-analysis/compute-regression-line-explain-water-consumption-16457

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An analyst would like to predict water consumption in a city based on daily temperature. She has gathered the following data for a random sample of n= 7 days.

Temperature ( C) 40 5 25 15 10 30 35

Water Consumption(million gallons) 225 25 150 100 75 125 175

Using the following sums and sums of squares and cross-products

Î£x= 160 Î£y= 875 SS(x)= 1042.857 SS(y)= 26,250 SS(xy)= 5,000

n= 7

Î£x= 160

Î£y= 875

SS(x)= 1042.857

SS(y)= 26250

SS(xy)= 5000

See the answer on the following pages

A) Compute the regression line to explain "water consumption" in terms of "temperature".

Regression equation: Y=a+bX

b=SS(xy)/ SS(x)= 4.7945 =5000/1042.857

Î£Y=na+bÎ£X

or 875=7*a + 4.7945*160

or ...

#### Solution Summary

Computes the regression line to explain "water consumption" in terms of "temperature", tests whether temperature is a significant predictor of water consumption, computes the coefficient of determination of the regression model and finds a 99% confidence interval for water consumption on a particular .