# Scatter Plot and data

Show all steps used in arriving at the final answers. Incomplete solutions will receive partial credit.

Data for a sample of houses sold recently in the suburb of a large metropolis are given below:

Area of House (hundreds of square feet) Selling Price (thousands of dollars)

20 250

19 220

27 350

28 390

30 320

15 200

25 360

23 290

18 210

35 410

(a) Do a scatter diagram for the data, insert the trend line and add the equation and R2 value to the diagram.

(b) Find SSxx, SSyy and SSxy.

(c) Determine the correlation coefficient. Comment on the value of the correlation coefficient.

(d) Find the regression equation manually. Compare with the equation obtained when doing the scatter diagram.

(e) Find SST, SSR and SSE.

(f) Find the degrees of freedom associated with the sum of squares in part (e).

(g) Find MSR and MSE.

(h) Summarize your findings as an ANOVA table.

(i) Find the coefficient of determination R2.

(j) Find standard error of the estimate se

(k) Test the hypothesis that Y and X are not related. That is, test H0: 1 = 0 vs. H1: 1 0 by using a t-statistic. Use = 0.05.

(l) Find the predicted value of Y given X = 24. Give an interpretation of the predicted value in the context of the problem.

(m) Find a 95% confidence interval for the mean value of Y given X = 24. Give an interpretation of the confidence interval in the context of the problem.

https://brainmass.com/statistics/scatter-plot/scatter-plot-data-490587

#### Solution Preview

Show all steps used in arriving at the final answers. Incomplete solutions will receive partial credit.

Data for a sample of houses sold recently in the suburb of a large metropolis are given below:

Area of House (hundreds of square feet) Selling Price (thousands of dollars)

20 250

19 220

27 350

28 390

30 320

15 200

25 360

23 290

18 210

35 410

(a) Do a scatter diagram for the data, insert the trend line and add the equation and R2 value to the diagram.

(b) Find SSxx, SSyy and ...

#### Solution Summary

The expert examines scatter plot data to find the MSR and MSE.