ageron / ageron/handson-ml2

Gaussian Mixture models mismatch predicted classes

Open
#221 1 comment 0 reactions 0 assignees View on GitHub
Dominant language
Jupyter Notebook
Stars
30k
Forks
13.1k
PR merge metrics
No merged PRs in 30d

Description

https://colab.research.google.com/github/ageron/handson-ml2/blob/master/09_unsupervised_learning.ipynb#scrollTo=iBdY4mAzvkHa

The code mismatches label predicted using unsupervised learning resulting in zero accuracy when I run the code in Colab.

y_pred = GaussianMixture(n_components=3, random_state=42).fit(X).predict(X)
mapping = np.array([2, 0, 1])
y_pred = np.array([mapping[cluster_id] for cluster_id in y_pred])

I suggest matching clustered labels to the most common y labels prior to the calculation of accuracy:

from copy import deepcopy
y_pred = GaussianMixture(n_components=3, random_state=42).fit(X).predict(X)
# replace prediction with the most common value
dic_val = {}
index = {}
for i in range(3):
newval = np.bincount(y[np.where(y_pred == i)[0]]).argmax()
index[i] = deepcopy(np.where(y_pred == i)[0])
dic_val[i] = deepcopy(newval)

for i in range(3):
y_pred[index[i]] = dic_val_copy[I]

My name is Ilya Rahkovsky, I am teaching a class using your textbook. Thank you for sharing your code.

Contributor guide

No contributing guide indexed for this repository

Assessment

This issue has not been assessed yet.

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.