Question

Suppose you fit a model with an influential point. With the point, the association of interest...

Suppose you fit a model with an influential point. With the point, the association of interest is just statistically significant, and without it, it is clearly not. What would you do?

Homework Answers

Answer #1

An influential point is an outlier that greatly affects the slope of the regression line. If your data set includes an influential point, here are some things to consider.

1. An influential point may represent bad data, possibly the result of measurement error. If possible, check the validity of the data point.

2. Compare the decisions that would be made based on regression equations defined with and without the influential point. If the equations lead to contrary decisions, use caution.

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