ValueError: Unknown metric function

ValueError: Unknown metric function

$ python -c "from sklearn.model_selection import cross_val_score; from sklearn.linear_model import LogisticRegression; import numpy as np; X=np.random.rand(10,2); y=np.random.randint(0,2,10); cross_val_score(LogisticRegression(), X, y, scoring='accuracyy')"
Traceback (most recent call last):
  File "<string>", line 1, in <module>
ValueError: Unknown metric function: accuracyy

Why this happens

• Misspelled or unsupported scoring name.

Fix

• Use a valid metric name like accuracy, f1, roc_auc, etc.

Wrong code

cross_val_score(LogisticRegression(), X, y, scoring='accuracyy')

Fixed code

cross_val_score(LogisticRegression(max_iter=500), X, y, scoring='accuracy')