unit 0.4 - Types of learningο
There are different types of learning in machine-learning, depending on how a desired relationship is acquired.
Supervisedο
\(y_d = f(x)\) with \(y_d\) as desired output and \(x\) as input.
Samples in the dataset are {{x1,y1}, {x2, y2}, {x3, y3}} β both \(x\) and \(y\) are provided as examples!
Examples:
a picture of a cat and a category number (1 = cat)
from a list of homework grades (a vector \(x\)) to final class grade \(y\)
generating an image from a text caption (Dall-E)
Unsupervisedο
There is only \(x\) here! Can we split \(x\) in groups?
Examples:
a zoo of animals, all of different kinds - group by kind
a set of points, group by closeness (k-means clustering)
a set of people, group by age, race, sex, β¦
Self-supervisedο
There is only \(x\) here! What is the desired output \(y_d\)? It is \(x\) itself!
Examples:
A portion of an image from the rest of the image (in-painting)
Removing noise from an image (de-noising)
predicting the next words from a previous set of words (language models like: chat-GPT, Gemini, Llama)
Reinforcement learningο
Learning to improve a task based on a performance metric. Self-improvement by comparing your results and trying to optimize gains.
Examples:
a program that learns to play chess, go, tic-tac-toe, etc. from playing the game
an athlete that wants to improve its moves to achieve better results
a robot that learns to pick-and-place objects by trying not to drop them, or improving speed
Imitation learningο
Copy a sequence of items from one instance to another. Learning to do something by observing someone else.
Examples:
learning to draw a figure by observing someone
learning to play music from a youtube video
learning a recipe from a video
learning to code machine-learning from video-lectures
learning to sing after someone
Summaryο
These are the most typical learning techniques and data samples in the respective datasets. The examples of applications are innumerable and we only mentioned a few here for brevity.
Referencesο
Just a few links here but there are many more. Search online for βtypes of learningβ.