Part_08_Estimators.md

Estimators objects: Fitting data:

The core object of scikit-learn is the estimator object.

All estimator objects expose afit method, that takes as input a dataset (2D array):

estimator.fit(data)
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Suppose``LogReg`` and``KNN`` are (shorthand names for) scikit-learn estimators.


# Supervised Learning Problem
LogReg.fit(SAheartFeat, SAheartTarget)

# Unsupervised Learning Problem
KNN.fit(IrisFeat)
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#### Estimator parameters:

All the parameters of an estimator can be set when it is instanciated, or by modifying the corresponding attribute:


estimator = Estimator(param1=1, param2=2)
estimator.param1
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#### Retrieving Estimator parameters: 

* When data is fitted with an estimator, parameters are estimated from the data at hand.
* All the estimated parameters are attributes of the estimator object ending by an underscore:


estimator.estimated_param_ 
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