NMF — A visual explainer and Python Implementation

 By Medium - 2021-03-19

Description

Gain an intuition for the unsupervised learning algorithm that allows data scientists to extract topics from texts, photos, and more, and build those handy recommendation systems. NMF explanation is…

Summary

  • Gain an intuition for the unsupervised learning algorithm that allows data scientists to extract topics from texts, photos, and more, and build those handy recommendation systems.
  • NMF NMF stands for Latent Semantic Analysis with the ‘Non-negative Matrix-Factorization’ method used to decompose the document-term matrix into two smaller matrices — the document-topic matrix (U) and the topic-term matrix (W) — each populated with unnormalized probabilities.
  • The Art of Topic Modeling The output of NMF changes each time you run it, and the topics are not resolved — the data scientist must infer the topic from the highest word frequencies per topic, using the H matrix.
  • This is a generative model where you can use these smaller matrices to reconstruct the original text.

 

Topics

  1. NLP (0.36)
  2. Backend (0.11)
  3. Machine_Learning (0.08)

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