Business Analytics

Two linear regression models are fit using the same data. The summary of model fits are shown below. What might be the reason that the input variable was found significant in model 1 but not in model 2? MODEL 1: Call:lm(formula=mpghp+wt+disp+drat+qsec,data=mtcars) Coefficients: Signif.codes:0***0.0010.010.050.1,1 Residual standard error: 2.558 on 26 degrees of freedom Multiple R-squared: 0.8489 , Adjusted R-squared: 0.8199 F-statistic: 29.22 on 5 and 26DF,p-value: 6.892e10 Residual standard error: 2.558 on 26 degrees of freedom Multiple R-squared: 0.8489 , Adjusted R-squared: 0.8199 F-statistic: 29.22 on 5 and 26DF,p-value: 6.892e10 MODEL 2 : Call: lm(formula=mpghp+wt+disp,data=mtcars) Residuals : Coefficients : Residual standard error: 2.639 on 28 degrees of freedom Multiple R-squared: 0.8268 , Adjusted R-squared: 0.8083 F-statistic: 44.57 on 3 and 28 DF, p-value: 8.65e11