Algorithms and Models

🔑 1. Algorithms in AI

An algorithm is a step-by-step set of rules or instructions that an AI system follows to solve a problem or make a decision.

  • Think of it as the recipe that tells the AI what to do with data.

Common AI Algorithms:

  • Decision Trees: Break data into branches to make predictions (used in credit scoring, medical diagnosis).
  • k-Nearest Neighbors (k-NN): Predicts by comparing new data to the most similar past data points.
  • Support Vector Machines (SVM): Separates data into categories with a decision boundary.
  • Neural Networks: Algorithms inspired by the human brain that recognize complex patterns (used in image and speech recognition).
  • Reinforcement Learning Algorithms: Learn by trial and error, using rewards and penalties (used in robotics, gaming, self-driving cars).

🔑 2. Models in AI

A model is the result of training an algorithm on data — it represents what the AI has “learned.”

  • If an algorithm is the recipe, the model is the finished dish.
  • Models can then make predictions or decisions on new, unseen data.

Types of AI Models:

  1. Supervised Learning Models
    • Trained on labeled data (input + correct answer).
    • Example: Predicting house prices based on features like size and location.
  2. Unsupervised Learning Models
    • Find hidden patterns in unlabeled data.
    • Example: Customer segmentation (grouping buyers with similar behavior).
  3. Reinforcement Learning Models
    • Learn by interacting with an environment and receiving rewards or penalties.
    • Example: AI learning to play chess or optimize warehouse robots.
  4. Deep Learning Models
    • A subset of neural networks with many layers (“deep”).
    • Example: Facial recognition, self-driving car vision systems.

How They Work Together

  1. Algorithm → Defines the process (e.g., “find the best line that separates cats from dogs”).
  2. Data → Feeds examples into the algorithm.
  3. Model → The trained system that can now recognize cats vs. dogs in new images.

In simple terms:

  • Algorithms are the methods (how AI learns).
  • Models are the outcomes (what AI has learned).