Machine Learning: How Computers Learn from Experience?

Imagine a program that starts playing checkers as a novice, but after hundreds of games defeats its creator. Or a car that learns to avoid obstacles on its own without detailed instructions from a programmer. Machine learning is no longer an abstract concept or science fiction topic – it has become a technology that transforms our everyday lives, opening doors to a world where computers improve through experience, much like humans do.
The Roots of Machine Learning: Arthur Samuel's Vision
The history of machine learning is inextricably linked to Arthur Samuel, who in 1959 defined this field as "the ability of computers to learn without being explicitly programmed." This groundbreaking approach stood in contrast to earlier methods, where each computer functionality had to be meticulously coded.
On February 24, 1956, Arthur Samuel’s Checkers program, which was developed for play on the IBM 701,
was demonstrated to the public on television.
Samuel didn't stop at theorizing. In 1952, he created a pioneering checkers program that could improve its skills with each game played. This self-learning program applied various functions and heuristics to limit the number of analyzed moves, and after each game, it adjusted its parameters to increase future effectiveness.
In 1963, Samuel's program achieved a spectacular success – it won a game against a human. Although this was not a checkers grandmaster, the event itself caused a sensation and demonstrated the true potential of machine learning. His work paved the way for further research, which resulted in the creation of more advanced systems, such as Jonathan Schaeffer's Chinook program, which won the US Open checkers championship in 1992 and defeated longtime world champion Marion Tinsley in 1994.
The culmination of this process was the complete solution of the game of checkers by Schaeffer's team. After 18 years of almost continuous work by dozens of computers, the Chinook program gathered complete information about all 5×10^20 possible moves in checkers, proving that with perfect play, the game must end in a draw.
The Essence of Machine Learning
To understand the essence of machine learning, it's worth referring to concepts presented during the historic Dartmouth Conference of 1956, which formally initiated the field of artificial intelligence. It was there that the vision of machines capable of learning and improving their skills was born.
Machine learning is a specialized branch of artificial intelligence, focusing on information processing and developing algorithms that imitate how the human mind learns and solves problems. Unlike traditional programming, where the programmer must precisely define all steps leading to problem-solving, in machine learning, the computer independently discovers patterns and relationships in the provided data.
A key element of this process is the model, which is trained on a dataset. Machine learning algorithms build a mathematical model based on sample data, called a training set or training data, to make predictions or decisions. Machine learning systems can learn from experience, meaning that the more data they receive, the more accurate their predictions can be.
This process can be compared to how children learn – through observation, experience, and feedback, computers refine their skills, adjusting internal parameters in response to new data. This ability to adapt represents the fundamental difference between traditional programming and machine learning.
Main Methods of Machine Learning
In the field of machine learning, several basic approaches can be distinguished, differing in how algorithms acquire and process knowledge. Each of these methods has its strengths and weaknesses and appropriate applications.
Supervised Learning
Supervised learning is a method in which an algorithm learns from labeled examples. In this approach, the training dataset contains attached problem solutions, called labels or classes. The algorithm analyzes this data, identifies patterns and relationships, and then applies the acquired knowledge to new, unknown data.
Among supervised learning algorithms, two main categories stand out: those solving regression problems (predicting values) and classification problems (predicting classes). An example of regression application might be forecasting a car's value based on its characteristics such as model, brand, production year, or mileage. Classification, on the other hand, can be used in anti-spam filters that categorize messages as spam or non-spam.
Popular supervised learning algorithms include linear and polynomial regression, decision trees, k-nearest neighbors method, support vector machines (SVM), naive Bayes classifier, random forest, logistic regression, and neural networks.
Unsupervised Learning
Unsupervised learning is an approach where the algorithm analyzes and groups unlabeled data based on their similarities or natural patterns. Unlike supervised learning, training data does not contain labels, and the algorithm must independently discover the structure and patterns in the data.
The main application of unsupervised learning is detecting non-obvious dependencies and grouping similar objects. Popular algorithms in this category are k-means clustering and PCA (Principal Component Analysis).
Unsupervised learning finds applications in customer segmentation, financial data analysis, or discovering patterns in large biological datasets.
Reinforcement Learning
Reinforcement learning is a method in which the model learns through experience, taking actions in an environment in a way that maximizes some reward. This type of learning is based on a system of penalties and rewards – the algorithm receives positive reinforcement for correct decisions and negative for incorrect ones, allowing it to improve its strategy.
This method is particularly close to how humans often learn – through trial and error, with feedback on the effectiveness of actions taken. This approach has its roots in behavioral psychology and learning theory.
Reinforcement learning is particularly useful in applications such as games, robot navigation, or process optimization, where the system must make sequences of decisions in a dynamically changing environment. This is the method behind the success of systems like AlphaGo, which defeated the world champion in the game of Go.
Semi-Supervised Learning
Complementing the main categories is semi-supervised learning, which combines features of supervised and unsupervised learning. This approach uses both labeled and unlabeled data, which is particularly useful in situations where labeling all training data is too costly or time-consuming.
Gradient Descent: A Fundamental Method for Training Neural Networks
One of the key techniques in machine learning, especially in the context of neural networks, is the gradient descent method. This fundamental mathematical approach allows for effective adjustment of weights in a neural network, enabling it to learn and improve performance.
Gradient descent is an iterative optimization algorithm used to find the minimum of a function. In the context of machine learning, this function is the loss (or error) function, which measures how well the model predicts based on training data. The goal is to find model parameters that minimize this loss function.
In this method, the gradient of the loss function indicates the direction of the fastest increase in function value. By moving in the opposite direction to the gradient (hence the name "gradient descent"), the algorithm step by step approaches the minimum of the loss function, which corresponds to optimal model parameters.
Gradient descent finds particular application in neural networks, where the number of parameters can reach millions. Thanks to this method, neural networks can effectively learn on large datasets, improve their predictions, and handle increasingly complex tasks.
Machine Learning and Moravec's Paradox
When discussing machine learning, it's worth referring to Moravec's paradox, which sheds interesting light on the differences between human and machine intelligence. This paradox indicates that tasks simple for humans (such as object recognition or spatial navigation) are often extremely difficult for machines, while tasks requiring complex calculations (such as playing chess) can be relatively easy for computers.
This paradox has significant implications for machine learning. It shows that human intelligence and learning are deeply rooted in our biological evolution, which for millions of years optimized our perceptual and motor abilities. Computers, on the other hand, developed in a completely different direction, perfecting computational and logical abilities.
Machine learning represents an attempt to overcome this paradox. Through various techniques, such as neural networks that to some extent mimic the structure of the human brain, machine learning systems try to teach computers tasks that are intuitive for humans but traditionally difficult for machines. On the other hand, machine learning leverages the natural predisposition of computers to process large amounts of information to solve problems beyond human capabilities.
The AI Effect and Machine Learning
When talking about machine learning, it's impossible to ignore the phenomenon known as the "AI effect". This refers to the tendency to depreciate achievements of artificial intelligence as they become common and understandable. When a computer learns to solve a difficult task that previously required human intelligence, we often start to perceive it as just a computational process, not a manifestation of intelligence.
Paradoxically, successes in machine learning contribute to this effect. As machine learning programs excel in image recognition, language translation, or product recommendation, these skills cease to amaze us, and we begin to see them as "just calculations" rather than intelligent behaviors.
This effect has significant implications for the development of machine learning and more broadly – artificial intelligence. On one hand, it leads to continuously raising the bar for what we consider intelligent machine behavior. On the other hand, it may lead to underestimating real progress in this field.
Machine Learning vs. Generative and General Artificial Intelligence
Machine learning forms the foundation for both generative artificial intelligence (GenAI) and is a key element in the pursuit of creating general artificial intelligence (AGI).
Generative AI uses advanced machine learning techniques, such as GANs (Generative Adversarial Networks) or transformers, to create new content – text, images, music, or video. It's like teaching computers creative skills that we previously considered exclusively human. At the heart of these systems are machine learning algorithms that learn to recognize patterns from huge datasets and generate new content consistent with these patterns.
General artificial intelligence, a hypothetical system possessing human cognitive abilities across a wide range of domains, would also be based on machine learning, though it would go beyond its current capabilities. AGI would require the ability to transfer knowledge between different domains, adapt to new tasks without the need for retraining, and deeper understanding of context and meaning – challenges that current machine learning systems are just beginning to address.
The difference between current machine learning systems and AGI resembles the difference between a narrowly specialized expert and a versatile generalist. Contemporary models can excel at specific tasks they were trained for, but they lack a broader understanding of the world and the ability to adapt in the face of completely new challenges.
The Turing Test and Machine Learning
The concept of the Turing Test, proposed by Alan Turing in 1950, has interesting connections with the development of machine learning. The Turing Test is based on the assumption that if a machine in conversation with a human cannot be distinguished from another human, it can be considered intelligent.
Machine learning, especially in the context of natural language processing, is a key element in the pursuit of creating systems that could pass the Turing Test. Contemporary language models such as GPT, Claude, or LaMDA use advanced machine learning techniques to generate texts indistinguishable from human ones. Although they still have their limitations, they represent the closest approximation to Turing's vision from 1950.
At the same time, the success of these models raises questions about the adequacy of the Turing Test as a measure of intelligence. Does the ability to generate convincing texts really indicate deeper understanding and intelligence, or is it just an effective simulation? This question directly relates to the broader discussion about the nature of intelligence and consciousness that has accompanied the development of machine learning since its beginnings.
The Dartmouth Conference and the Birth of Machine Learning
At this point, it should be emphasized again that the history of machine learning is inextricably linked to the Dartmouth Conference of 1956, which officially initiated the field of artificial intelligence. It was there, during an eight-week meeting of scientists from various disciplines, that the term "Artificial Intelligence" was first officially used, and systematic research began on methods that today we know as machine learning.
Conference participants, including John McCarthy, Marvin Minsky, Nathaniel Rochester, and Claude Shannon, discussed, among other things, the possibilities of creating machines that could "think" and learn like humans. It was during this conference that Allen Newell and Herbert A. Simon presented the Logic Theory Machine – one of the first computer programs capable of automatic reasoning and proving mathematical theorems.
Although the term "machine learning" was formally coined by Arthur Samuel a few years later, it was at the Dartmouth Conference that the foundations for this field were laid, defining key problems and research directions. It's worth noting that many conference participants, including Minsky and Simon, later contributed significantly to the development of machine learning methods.
Applications and Future of Machine Learning
Machine learning finds applications in countless areas of life and economy:
Medicine
Machine learning systems can analyze medical images, assist in disease diagnosis, or predict treatment effectiveness. Algorithms analyzing X-ray images can detect cancerous changes with accuracy comparable to experienced radiologists.
Finance
In the financial sector, machine learning serves to detect fraud, assess credit risk, or forecast market trends. Algorithms analyze transaction patterns to identify suspicious operations and prevent fraud.
Transportation
Systems based on machine learning control autonomous vehicles, optimize routes, and manage traffic flow. Tesla cars use machine learning to avoid collisions by monitoring the environment and responding to potential threats.
Marketing
In marketing, machine learning enables personalization of customer communication, prediction of sales trends, or customer segmentation. Recommendation systems, used by companies such as Amazon or Netflix, analyze user behaviors to propose products and content tailored to their preferences.
Entertainment
Generating music, images, or texts are areas where machine learning opens new creative possibilities. From generating musical compositions, through creating images in a specific style, to writing dialogues for games – machine learning is finding increasingly wider application in the entertainment industry.
Industry
In the industrial sector, machine learning systems optimize production, predict equipment failures, or improve product quality. Predictive maintenance systems, based on sensor data analysis, can predict machine failure before it occurs, saving time and costs.
Ethical Aspects of Machine Learning
With the development of machine learning and its increasing influence on our lives, important ethical questions arise:
Algorithm Bias
Machine learning algorithms learn from historical data, which may contain hidden biases. If the training data is biased, the algorithm will also be biased, which can lead to discrimination in areas such as recruitment, credit approval, or justice.
Data Privacy
Machine learning often requires access to large amounts of data, which raises questions about privacy and security of personal information. Who has access to this data? How is it used? Can it be used in a way that is inconsistent with the intentions of the people it concerns?
Responsibility for Decisions
Who bears responsibility for decisions made by machine learning systems? Is it the algorithm creator, the implementing company, or perhaps the end user? This question becomes particularly important in the context of autonomous systems, such as driverless cars or medical applications supporting diagnosis.
Algorithm Transparency
Many advanced machine learning models, especially deep neural networks, operate on the principle of a "black box" – it's difficult to explain why they made a particular decision. This raises questions about transparency, interpretation, and explainability of such systems, especially when they affect important aspects of human life.
Machine Learning as a Digital Oracle
With certain reservations, contemporary machine learning systems can be compared to a kind of digital oracle. Like ancient oracles, modern models based on machine learning integrate huge amounts of data, analyze them, and generate responses that often go beyond what a single person would be able to infer.
However, like oracles, these answers are not always unambiguous or flawless. Machine learning systems operate based on data that may be incomplete or biased. Their "oracular" answers are only as good as the data they were trained on.
Moreover, like ancient oracles, machine learning systems often require interpretation of their results by experts who understand the context and limitations of the model. This emphasizes that despite enormous progress, machine learning remains a tool supporting human decision-making, not its replacement.
Summary
Machine learning, defined by Arthur Samuel as the ability of computers to learn without direct programming, has come a long way from the pioneering checkers-playing program to advanced systems generating texts, images, and music.
At the heart of this transformation lies a fundamental change in approach – from programming computers step by step to creating systems that can learn from data and their own experiences. This paradigm shift has opened doors to solving problems that previously seemed impossible to overcome.
The future of machine learning looks fascinating. New research directions, such as federated learning or neuromorphic computing, may lead to even more advanced systems. At the same time, growing awareness of ethical challenges associated with machine learning leads to the development of more responsible and transparent approaches.
Machine learning, although still far from true human intelligence, constitutes one of the most important foundations of modern technology. Understanding its basics, possibilities, and limitations becomes increasingly important in a world where algorithms increasingly influence our daily lives.
Note!
This article was developed with the support of Claude 3.7 Sonnet, an advanced AI language model. Claude also assisted with translating this article from Polish to English. While Claude helped with organization and presentation of content, the article is based on reliable sources about machine learning. It maintains an objective approach to the topic, presenting both historical development, basic concepts, as well as contemporary applications and challenges associated with this technology. If you notice any translation errors, please let me know in the comments.