Supervised learning
Supervised learning is a type of machine learning that involves training a model on a labeled dataset to make predictions about new, unseen data. It is one of the most used techniques in artificial intelligence (AI) and has applications in various fields such as computer vision, natural language processing, and predictive modeling.
The basic concept of supervised learning is based on the idea of providing the model with input-output pairs or examples to learn the underlying patterns and relationships between the features of the data. These input-output pairs are known as the training data and are used to teach the model how to make accurate predictions.
There are two main types of supervised learning: classification and regression. In classification, the goal is to predict which category or class an input belongs to, while in regression, the goal is to predict a numerical value or quantity. For example, predicting whether an email is spam (classification) or predicting house prices (regression).
To illustrate how supervised learning works, let us take a simple example of classifying fruits based on their color and shape. We provide the model with a dataset that includes different types of fruits along with their corresponding colors and shapes. The model learns from this training data and then when presented with a new fruit with unknown color and shape, it uses its learned knowledge to classify it into one of the existing categories.
Now let us dive deeper into some key concepts related to supervised learning:
- Training Data: As mentioned earlier, training data plays a crucial role in supervised learning. It contains both input features (attributes or characteristics) and their corresponding output labels (the desired prediction). The quality and quantity of training data affect the performance of a model.
- Features: Features refer to measurable characteristics or attributes that describe the input data. In our previous example, color and shape were features for classifying fruits.
- Label: A label is an output value associated with each set of features in the training data. It can be a class label (i.e., category or group) in classification or a numerical value in regression.
- Model: A model is an algorithm or mathematical function that represents the relationship between the input features and output labels. The goal of supervised learning is to train the model to accurately predict output values for new, unseen data.
- Training: Training refers to the process of using the labeled training data to teach the model how to make predictions. During training, the model iteratively adjusts its parameters based on the training data until it can accurately predict output values.
- Testing/Evaluation: After training, we evaluate the performance of our model using a separate dataset called testing or evaluation dataset. This dataset contains examples that were not used during training and serves as a benchmark for measuring how well our model generalizes to new data.
- Overfitting: Overfitting occurs when a model becomes too complex and fits too closely to the training data, resulting in poor performance on unseen data. This often happens when there is noise or irrelevant features in the training data.
- Underfitting: Underfitting occurs when a model is not complex enough to capture all relevant patterns and relationships in the data, leading to poor performance on both training and testing data.
Supervised learning
It is an essential concept in AI that involves teaching models with labeled data to make accurate predictions about new, unseen data. Understanding these key concepts is crucial for developing effective solutions using supervised learning techniques.