Question

help please.. show work

2.041 0.25 1.4122 1.2830-2 3.01 Independent variables with a p-value >.05 (or with confidence intervals including 0) are considered unuseful Assume the non-contributing independent variables are dropped. The following table detals the coefficien List any independent variables that do not contribute to the usefulness of the model ts for the 'r Note: df is now t then above (since fewer x variables in model). So, look up a new critical value for t. Coefficients 40 0.21 Standard Error Lower 95% Intercept XXx ххх 2.754 Write the Calculated Regression Line for 'revised" model) Solve for YA (revised model) 10 and X4-15, Y^ If X2 Written Interpretation for the confidence interval for the slope of X4 for 'revised' model) we .ate

Answer 1

The estimated regression line is

у = 0.212.2-2.754.4 + 40

When x_2=10 and x_4=15 then

y = 0.21 * 10-2.754 * 15 + 40 0.79

When x_2=7 and x_4 =9, then

y = 0.21 * 7-2.754 * 9 40 16.684

n=48 so the t value for 46 degrees of freedom for 95% confidence is 2.013.The margin of error is 2.013*S.E for x_4 from the above table

Margin of Error(M.E)=2.013*1.0166=2.046

The 95% confidence interval for the coefficient of x_4 or the slope of x_4 is (slope value-M.E,slope value+M.E) between -4.8 and -0.7 .95 percentage of the times we could find the true value of slope within the confidence interval.