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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

    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 28ºC.

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    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

    Σx= 160 Σy= 875 SS(x)= 1042.857 SS(y)= 26,250 SS(xy)= 5,000

    n= 7
    Σx= 160
    Σy= 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

    ΣY=na+bΣX
    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 .

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