Friday, March 28, 2025

CH_03_03: Types of ML : Semi-Supervised Learning

Semi-Supervised Learning is a machine learning approach that falls between supervised and unsupervised learning. It utilizes a small amount of labeled data along with a large amount of unlabeled data to improve learning efficiency and accuracy.


Types of Semi-Supervised Learning:

Self-Training

A model is first trained on labeled data, then used to label some of the unlabeled data, which is added back for further training.

Example: A spam detection model is trained on a small set of labeled emails and then used to label additional emails, improving accuracy over time.

Co-Training

Two models are trained on different feature sets of the same data and help label unlabeled data for each other.

Example: A face recognition system might use both image pixels and metadata (e.g., timestamps) as separate features to learn better.

Graph-Based Methods

Data points are represented as nodes in a graph, and labels propagate through connected nodes.

Example: Social media friend recommendations use graph structures to infer new connections based on labeled users' preferences.

Generative Models

A probabilistic model is trained to understand data distribution and generate labels for unlabeled data.

Example: A model trained on a few labeled medical images generates synthetic labels for new images.

Use Cases:

Healthcare: Medical diagnosis with a limited number of labeled cases.

Speech Recognition: Using labeled audio data and unlabeled speech recordings to improve accuracy.

Text Classification: Sentiment analysis with a few labeled reviews and a vast number of unlabeled ones.


No comments:

Post a Comment