I am asked to do a regression analysis on
distance ~ speed in R. Using the following code:
fit <- lm(dist ~ speed) summary(fit)
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 ***
I am asked:
Can we conclude that the slope is greater than zero? Can we conclude that the intercept is smaller than zero? Report the relevant p-values to support your conclusions.
I am not exactly sure what they ask me to do in this question. Can I draw the conclusions from information obtained by the
summary-command or should I make a confidence interval? I would say the $p$-values in this case show that there is enough statistical significance to conclude that the intercept < 0 and speed > 0.