Machine learning

From AI Wiki
See also: Machine learning terms and artificial intelligence






Introduction to Machine Learning

Machine learning is a branch of artificial intelligence that deals with the design and development of algorithms and models that allow computers to learn from data and make predictions or decisions without being explicitly programmed. The aim is to create systems and models which can automatically improve their performance over time based on experience, thus solving real-world problems.

Types of Machine Learning

Machine learning consists of three primary approaches:

  1. Supervised learning: In supervised learning, an algorithm is trained on a labeled dataset where each input and its associated label are known. The goal is to learn a mapping between input and output so that the model can accurately predict future data without being informed beforehand.
  2. Unsupervised learning: Unsupervised learning involves training an algorithm on an unlabeled dataset, where the output or label for each input is unknown. The goal is to uncover patterns or structures within the data by grouping similar examples together.
  3. Reinforcement learning: Reinforcement learning is an approach in which an algorithm learns to make decisions by taking actions in an environment to maximize a reward signal. It receives feedback in the form of rewards or penalties, which it uses to adjust its decision-making strategy accordingly.

Algorithms and Models

Machine learning involves many algorithms and models:

  1. Linear regression: a straightforward method for predicting continuous output based on input features.
  2. Logistic regression: an approach used to predict binary outcomes from given input features.
  3. Decision tree: a tree-like model for making decisions or predictions based on input features.
  4. Random forest: an ensemble of decision trees used for both regression and classification tasks.
  5. Neural network: models inspired by the structure and function of the brain with neurons and hidden layers, used for various complex tasks.
  6. Support vector machine (SVM): Classification method that finds boundary that best separates different classes in data set.
  7. K-nearest neighbor (KNN): A classification algorithm that predicts the label of a new data point by looking at its closest neighbors in training data.


Machine learning has many applications, such as:

  1. Image recognition and computer vision
  2. Natural language processing
  3. Speech recognition and synthesis
  4. Recommendation systems
  5. Fraud detection
  6. Predictive maintenance
  7. Healthcare
  8. Financial services

Explain Like I'm 5 (ELI5)

Let's say you have a toy box full of different toys. Every day, you play with some of them and eventually decide which ones are your favorites - much like how computers learn to do things on their own.

Imagine you have a computer program trying to figure out which toys you like best. At first, it doesn't know anything and therefore makes guesses based on the rules given. However, as more toys are played with, and feedback is given about what works and doesn't work, the program gets better at anticipating future preferences. This process is known as "machine learning".

Just as you keep learning and discovering new favorites, your computer program can keep improving at figuring out what appeals to you. That is why machine learning is so powerful - it allows the computer to improve itself without being explicitly programmed for this task.