Stat 20: Intro to Probability and Statistics
Lecture 9: Regression Methods
Tessa L. Childers-Day
UC Berkeley
7 July 2014

Today’s Goals
The Intuition
The Mechanics
Some Caveats
Simplification
By the end of this lecture...
You will be able to:
Decide if regression is applicable to a given situation
Construct and interpret regression estimates for averages and
individuals
Calculate the equation of a regression line
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Today’s Goals
The Intuition
The Mechanics
Some Caveats
Simplification
Correlation is great, but...
Correlation is a very limited quantity
Strength of linear association
between
x
and
y
Doesn’t actually
do anything
with the association
We believe there is a linear
association. Let’s use it.
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