## Influential Observations

This section discusses the notion of influence and describes what makes a point influential. It introduces the concepts of leverage and distance, which are useful to detect influential observations.

### Questions

**Question 1 out of 2.**

Which of the following statements are true about studentized residuals?

They are the deviations of the observed values from the fitted line.

They're closely related to the errors of prediction of the observation.

Large studentized residuals will lead to large influence on the regression model in all circumstances.

**Question 2 out of 2.**

Which of the following would have the largest influence? (h is the leverage, R is the studentized residual)

X:1, Y:2, h:0.39, R:1.2

X:2, Y:3, h:1.23, R:-0.13

X:3, Y:5, h:1.21, R:-1.68