#Plot of stopping distance over speed
plot(cars,speed ~ dist)
#Creation of Linear Model
Cars.lm <- lm(dist ~ speed, data=cars)
Cars.lm
##
## Call:
## lm(formula = dist ~ speed, data = cars)
##
## Coefficients:
## (Intercept) speed
## -17.579 3.932
#plot of stopping distance over speed with ab line
plot(dist ~ speed,cars)
abline(Cars.lm)
#summary of model
summary(Cars.lm)
##
## Call:
## lm(formula = dist ~ speed, data = cars)
##
## Residuals:
## Min 1Q Median 3Q Max
## -29.069 -9.525 -2.272 9.215 43.201
##
## Coefficients:
## Estimate Std. Error t value Pr(>|t|)
## (Intercept) -17.5791 6.7584 -2.601 0.0123 *
## speed 3.9324 0.4155 9.464 1.49e-12 ***
## ---
## Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
##
## Residual standard error: 15.38 on 48 degrees of freedom
## Multiple R-squared: 0.6511, Adjusted R-squared: 0.6438
## F-statistic: 89.57 on 1 and 48 DF, p-value: 1.49e-12
plot(fitted(Cars.lm),resid(Cars.lm))
#Q-Q model of residuals
qqnorm(resid(Cars.lm))
qqline(resid(Cars.lm))
