Page 153 - Statistics II for Dummies

Chapter 8

Yes, No, Maybe So:

Making Predictions by Using

Logistic Regression

In This Chapter
▶ Knowing when logistic regression is appropriate
▶ Building logistic regression models for yes or no data
▶ Checking model conditions and making the right conclusions

veryone (even yours truly) tries to make predictions about whether or
Enot a certain event is going to happen. For example, what’s the chance
it’s going to rain this weekend? What are your team’s chances of winning the
next game? What’s the chance that I’ll have complications during this sur-
gery? These predictions are often based on probability, the long-term percent-
age of time an event is expected to happen.
In the end, you want to estimate p, the probability of an event occurring. In
this chapter, you see how to build and test models for p based on a set of
explanatory (x) variables. This technique is called logistic regression, and in
this chapter, I explain how to put it to use.

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