# Statistics: Determining Regression Coefficients

Please use data of the attached two tables to answer the following questions about Pb 9.24.

C) Find the regression coefficiet a and b.

K)iii. Construct the 99% confidence interval for ?.

I)iii. Construct the 99% confidence interval for ?.

(p) Compute the correlation coefficient r.

q)ii. Construct the 95% confidence interval for ?.

Data are on the two attached tables(9.19 and 9.20).

Problem 9.24:

The ejection fraction at maximal exercise was measured before, X, and after, Y , training.

X = 0.556, Y = 0.564, [x^2] = 0.30284, [y^2] = 0.46706, and [xy] = 0.2809.

Is there association (? = 0.05) between the two ejection fractions? If yes, do tasks (c), (k-iii), (l-iii), (p), and (q-ii) above.

Is there a change (? = 0.05) between the two ejection fractions?

If yes, find a 95% confidence interval for the average difference.

#### Solution Preview

See the attached file. Hope this will help. Thanks

Problem 9.24:

The ejection fraction at maximal exercise was measured before, X, and after, Y , training.

X = 0.556, Y = 0.564, [x^2] = 0.30284, [y^2] = 0.46706, and [xy] = 0.2809.

Is there association (a= 0.05) between the two ejection fractions?

X 0.556

Y 0.564

[x^2] 0.30284

[y^2] 0.46706

[xy] 0.2809

First we calculate the degree of linear relationship between the two ejection fractions.

Pearson product moment correlation coefficient

r= 0.746893677

Now test wehther the correlation coefficient is significantly different from zero.

We do the t -test for testing the hypothesis ρ = 0. The formula for calculating t-statistic is

No. of observations n= 19

= 4.631253036

Degrees of freedom 17

Significance Level 0.05

Critical ...

#### Solution Summary

This solution provides a detailed, step by step calculation of the given statistics problem.