Supervised Learning vs. Unsupervised Learning

Today, machine learning (ML) has cut a path through sectors, including health care, finance, and entertainment. These developments require machines to analyze datasets using one of two methods: supervised learning and unsupervised learning.

While both approaches have their own pros and cons, they have differing training methods and pre-required datasets that make them beneficial in specific use cases.

See below to learn all about supervised learning and unsupervised learning in the ML market:

What is Supervised Learning?

Supervised learning requires human supervision to label and tame raw data. Once the data is classified, the model learns the relationship between input and output data for the engineer to apply to a new dataset and predict outcomes.

Compared to the unsupervised approach, supervised learning has higher accuracy and is considered trustworthy, due to the human involvement. Moreover, the approach allows users to produce an input based on prior references and experiences.

What is Unsupervised Learning?

Unsupervised learning involves identifying patterns in raw and unlabelled datasets. It is a hands-off approach — the data scientist will set model parameters, but the data processing will continue without human intervention.

Unsupervised learning works without labels, which is a major drawback to analyzing comparative models. However, the technique works well for exploratory analysis by identifying data structures. Unsupervised learning is the go-to method for a data scientist looking to create customer segmentation with given data. Moreover, the approach is ideal for offering initial insights when human predictions or individual hypotheses are likely to fail.

Features

Supervised Learning

• Training data: Supervised learning requires both labeled input and output data variables.
• Learning method: Under supervised learning, the model interprets the relationship between labeled input and output data to predict outcomes.
• Resource-intensive: Supervised learning is resource-intensive due to the requirement of data scientists to label data.
• Complexity: Relatively simpler programs like R and Python are used in supervised learning.
• Algorithm used: Supervised learning uses classification trees, vector machines, linear and logistics regression, neural networks, and random forests.
• Number of classes: Known
• Drawback: The training involved in the supervised learning approach can be time-consuming. Although labeling might seem like a simple task, it is quite a tedious job. Therefore, the labeling of the input and output data can only be done by an expert data scientist.

Unsupervised Learning

• Training data: Unsupervised learning involves the processing of raw and unlabeled data. Moreover, only input data is accommodated in the process.
• Learning method: Unsupervised learning learns patterns via an unlabeled, raw training dataset to find the inherent trend.
• Application: Unsupervised learning is done to cluster similar data points to identify patterns.
• Resource-intensive: Compared to supervised learning, unsupervised learning is less resource intensive and requires no human intervention.
• Complexity: Unsupervised learning requires computationally complex programs to work with large amounts of unlabelled data.
• Algorithms used: Unsupervised learning uses K-means, cluster algorithms, and hierarchical clustering.
• Number of classes: Not known
• Drawback: It is difficult to give a sufficient level of explanation or to validate the output variables without human intervention.

Points to Consider

Before picking a machine learning approach, consider:

• Evaluation of the dataset: Check whether your data is labeled or unlabeled. If it is unlabeled, do you have the required expertise to carry out the labeling of the data?
• Know your goals: Do you want to go for classification or regression (supervised learning) or clustering or association (unsupervised learning)?
• Size of the dataset: Is your dataset too large to be handled by supervised learning? Are you looking to generate accuracy or precision for your data trends?

Benefits

Supervised Learning

Supervised learning is mainly used to recognize and classify unseen data into specific categories, such as images, documents, and words. Other areas where the approach has advantages are data prediction and forecasting trends and outcomes, like projecting house pricing or customer purchase patterns. Supervised learning mostly solves two categories of problems: regression and classification.

• Regression typically establishes causality between an independent and dependent variable using linear, logical, and polynomial techniques, which is ideal for predicting numerical values, like annual revenues, shares, and market projections. for a company.
• Classification problems sort test cases into separate classes for better identification through decision trees and linear classifiers. If you want to divide spam mails from your inbox, then classification criteria are at play here.

Unsupervised Learning

Unsupervised learning usually involves representation learning, clustering, and dataset density estimation without official labels through an autoencoder algorithm. Benefits of unsupervised learning include:

• The method has a use case in image compression and user segmentation, which is ideal for data clustering based on similarities and differences.
• Association analysis determines the variable relationship in market conditions, search engines, and product carts of e-commerce websites. Next time you see the Based on Your Search results, know unsupervised learning is at work here.
• Dimensionality reduction is an ideal technique for heavy datasets. The method compartmentalizes inputs into manageable sizes while also maintaining their integrity.

Use cases

Supervised Learning

• Content recommendation: A streaming provider’s supervised machine learning algorithm can produce personalized recommendations based on an individual’s previous activity and favorite genres as well as content consumed by other users with similar interests. 
• Spam detection: Supervised learning can help clear your inbox by detecting spam. Email providers deploy supervised learning techniques to recognize and segment emails with specific keywords into the spam folder.
• Identity verification: Most websites employ Recatch to verify authentic users through supervised ML tools. Facial recognition systems use supervised learning to differentiate and identify individuals. Traffic lights can operate on a similar concept to fine users violating traffic rules.
• Bioinformatics: Supervised learning can help in storing genetic information, like retinal screening, fingertips, iris textures, swabs, and eyes. A smartphone can use the technique to unlock itself every time a user puts their fingerprint on the sensor.

Unsupervised Learning

• Anomaly detection: Unsupervised learning is used to pinpoint specific logistical barriers and detect mechanical issues during predictive maintenance. The technique can also help in fintech to spot scams and save resources.
• Targeting specific consumer market: Unsupervised learning deploys clustering tools to classify and segment users with similar traits to create personas for targeted marketing.
• Clinical studies: Studying and reading genes and tissue expression and making predictive analysis for early stage diseases are examples of unsupervised learning’s clustering approach.