sklearn का cross_val_score()

Python में Model Validation

Kasey Jones

Data Scientist

cross_val_score()

from sklearn.model_selection import cross_val_score
from sklearn.ensemble import RandomForestClassifier
rfc = RandomForestClassifier()

estimator: उपयोग करने वाला मॉडल

X: predictor डेटासेट

y: response array

cv: cross-validation splits की संख्या

cross_val_score(estimator=rfc, X=X, y=y, cv=5)
Python में Model Validation

scoring और make_scorer का उपयोग

cross_val_score का scoring पैरामीटर:

# Load the Methods
from sklearn.metrics import mean_absolute_error, make_scorer
# Create a scorer
mae_scorer = make_scorer(mean_absolute_error)
# Use the scorer
cross_val_score(<estimator>, <X>, <y>, cv=5, scoring=mae_scorer)
Python में Model Validation

sklearn की सभी methods लोड करें

from sklearn.ensemble import RandomForestRegressor
from sklearn.model_selection import cross_val_score
from sklearn.metrics import mean_squared_error, make_scorer

मॉडल और scorer बनाएँ

rfc = RandomForestRegressor(n_estimators=20, max_depth=5, random_state=1111)
mse = make_scorer(mean_squared_error)

cross_val_score() चलाएँ

cv_results = cross_val_score(rfc, X, y, cv=5, scoring=mse)
Python में Model Validation

परिणाम एक्सेस करना

print(cv_results)
[196.765, 108.563, 85.963, 222.594, 140.942]

mean और standard deviation रिपोर्ट करें:

print('The mean: {}'.format(cv_results.mean()))
print('The std: {}'.format(cv_results.std()))
The mean: 150.965
The std: 51.676
Python में Model Validation

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Python में Model Validation

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