In the first part we explored the fundamentals of machine learning, analyzing 2 types of it: supervised and unsupervised learning in detail. In this second part we will delve into more advanced ML techniques and their applications.
Reinforcement learning
Reinforcement learning is a machine learning technique in which an agent learns to make sequential decisions to maximize a cumulative reward. Unlike the labeled data from which supervised ML learns, here the agent interacts with an environment and improves its actions based on the feedback it receives.
Common applications of reinforcement learning are varied. In games, such as AlphaGo and Google DeepMind, these algorithms have been used to beat human champions in complex games. In robotics, reinforcement learning teaches robots to walk or manipulate objects. Finally, it is widely used in recommendation systems to optimize user interactions and improve the experience.
Semi-supervised learning
In this model, a combination of labeled and unlabeled data is used. It is very useful when you have large amounts of unlabeled data and only a little amount of labeled data, because it can reduce the time and cost of manual labeling.
Self-supervised learning
In this approach, the model uses part of the data to automatically generate labels for the rest of the data as well. It is used in natural language processing (NLP) and computer vision, where the model creates predictions based on patterns detected in the data.
Transfer learning
Transfer learning exploits the knowledge acquired by a model trained on a certain task to improve performance on another task related to the first. It is very useful when you have limited data for the second task, because it allows you to transfer knowledge from one domain to another.
Meta-learning
Also known as “Learning to Learn,” meta-learning aims to develop algorithms that can quickly adapt to new tasks with little information available. This is fundamental to develop AIs that can learn exactly like humans, which learn differently depending on different situations.
Comparing types of machine learning
Each ML approach has some advantages and disadvantages. Supervised learning, for example, is very powerful for predictive tasks, but requires a lot of labeled data. The unsupervised one is useful for exploratory analysis, but starting from unlabeled data it can be less precise. Reinforcement learning excels in dynamic situations but can be very computationally intensive. Semi- and self-supervised approaches offer a trade-off between accuracy and manual workload, while transfer learning and meta learning pave the way for more general, flexible, and adaptable models.
Real World Applications of types of machine learning
Many companies have implemented ML techniques and models to gain various competitive advantages. Google, for example, uses reinforcement learning to optimize energy consumption in its data centers, saving millions of dollars. Netflix uses supervised and unsupervised learning for personalized recommendations and to improve the user experience.
Challenges and future developments of various types of Machine Learning
While there is significant progress, ML will still face several challenges. Immediately visible are the need for large quantities of high-quality data, the management of bias, the difficulties of interpreting complex models. In any case, the prospects for the future are promising. Emerging technologies such as quantum computing could revolutionize this field by making models even more powerful.