Definition:
Supervised machine learning is a type of machine learning where the model is trained on a labeled dataset.
The labeled dataset consists of examples where each example is associated with a label.
The goal of supervised machine learning is to learn a mapping function from the input data to the corresponding labels.
This mapping function can then be used to make predictions on new, unseen data.
Types of Supervised Machine Learning
1. Classification: Classification is the task of assigning a class label to an input data point.
Example: A classification model could be used to classify emails as spam or not spam, or to classify images of handwritten digits.
2. Regression: Regression is the task of predicting a continuous numerical value.
Example: A regression model could be used to predict the price of a house based on its size, location, and other features, or to predict the future sales of a product.
Supervised Machine Learning Algorithms
Some of the most common algorithms include:
1. Linear regression: Linear regression is a simple and interpretable algorithm that can be used for both classification and regression tasks. It is a good choice for tasks where the relationship between the input data and the labels is linear.
2. Logistic regression: Logistic regression is a popular algorithm for classification tasks. It is a good choice for tasks where the labels are binary (e.g., yes/no, true/false).
3. Support vector machines (SVMs): SVMs are a powerful algorithm for both classification and regression tasks. They are known for their ability to handle high-dimensional data and their robustness to outliers.
4. Decision trees: Decision trees are a versatile algorithm that can be used for both classification and regression tasks. They are easy to interpret and can handle categorical data.
5. Random forests: Random forests are an ensemble algorithm that combines multiple decision trees to improve performance. They are a popular choice for classification and regression tasks.
Applications of Supervised Machine Learning
- Spam filtering: Can be used to filter spam emails from inboxes.
- Medical diagnosis: Can be used to diagnose medical conditions based on patient data.
- Fraud detection: Can be used to detect fraudulent transactions in financial data.
- Customer segmentation: Can be used to segment customers based on their demographics and behavior.
- Recommendation systems: Can be used to recommend products, movies, and other items to users.
Steps in Supervised Learning:
- Data Collection: Gather a dataset containing input features and corresponding target labels.
- Data Preprocessing: Clean, handle missing values, scale features, and split data into training and test sets.
- Model Selection: Choose an appropriate model or algorithm based on the problem and data characteristics.
- Model Training: The model learns from the training data by adjusting its parameters to minimize prediction errors.
- Model Evaluation: Assess the model’s performance using metrics like accuracy, MSE, precision, recall, etc., on a test set.
- Model Tuning: Fine-tune model hyperparameters or select a different algorithm if performance is inadequate.
- Model Deployment: Deploy the trained model to make predictions on new, unseen data in real-world applications.
References:
- Machine Learning: A Probabilistic Perspective by Kevin P. Murphy, MIT Press, 2012.
- Machine Learning: A Practical Guide by Florian Deisenroth, Faisal Abdulle, and Christopher Ong, Cambridge University Press, 2020.