What is Supervised learning?

Supervised learning is a type of machine learning where the algorithm learns from labeled data, meaning the input data is paired with corresponding output labels. The goal of supervised learning is to learn a mapping function from input variables to output variables based on the labeled training data.

Here's a detailed explanation of supervised learning:

Labeled Data:- In supervised learning, the training dataset consists of input-output pairs, where each input data point is associated with a corresponding output label. 

For example, in a classification task, the input data might be images of handwritten digits, and the output labels would be the digit each image represents (e.g., 0,1, 2, ..., 9).

Similarly, in a regression task, the input data might be features of houses, and the output labels would be the corresponding house prices.

Training Process:- During the training process, the algorithm learns to map input data to output labels by minimizing a loss function, which measures the difference between the predicted outputs and the true labels. The algorithm iteratively adjusts its parameters (e.g., weights in a neural network) to minimize the loss function using optimization techniques such as gradient descent.

Types of Supervised Learning:-

a. Classification:- In classification tasks, the output variable is categorical, meaning it belongs to a specific class or category. The goal is to predict the class label of new input data points.

Example: Email spam detection, where the input is an email and the output is either "spam" or "not spam."

b. Regression:- In regression tasks, the output variable is continuous, meaning it can take any numerical value within a range. The goal is to predict a quantity or value based on input features.

Example: House price prediction, where the input features are characteristics of a house (e.g., size, number of bedrooms) and the output is the price of the house.

Evaluation and Testing:- Once the model is trained on the labeled training data, it is evaluated on a separate set of labeled test data to assess its performance and generalization ability. Common evaluation metrics for classification tasks include accuracy, precision, recall, and F1-score. For regression tasks, metrics such as mean squared error (MSE) and mean absolute error (MAE) are commonly used to evaluate performance.

Applications of Supervised Learning:-

Supervised learning has numerous applications across various domains, including:-

   -- Image and object recognition

   --Speech recognition

   -- Natural language processing (e.g., sentiment analysis, named entity recognition)

   -- Medical diagnosis

   -- Financial forecasting

   -- Autonomous driving

In summary, supervised learning is a fundamental paradigm in machine learning where the algorithm learns from labeled data to make predictions or decisions about new, unseen data. It is widely used in various real-world applications and forms the basis for many advanced machine learning techniques.