Machine learning is fundamentally shifting our approach to solving complex problems. In contrast to traditional programming which depends on a strict set of rules, ML systems develop their own algorithmic strategies to solve problems by learning from datasets. This distinction marks a shift from a rule-based system to one that learns and evolves autonomously.
In traditional programming, the programmer is the one who creates a set of rules and feeds them to the computer. If they get unsatisfactory results, they go back to the drawing board – amend the initial set of rules in the hopes of improving outcomes.
In contrast, machine learning empowers computers to discern optimal rules independently. It does so by providing the computer with examples of the issues we are looking to solve and leaving it to the computer to create a machine-learning model.
Let's delve further into the definition of machine learning, exploring its core principles, main types of ML, algorithms, and real-world applications and see how it can fuel your future project.
Machine learning is the scientific study of algorithms and statistical models that enable computer systems to perform specific tasks independently (without human involvement), based on the results of a learning process.
Machine learning is a component of artificial intelligence, where AI is a broader spectrum of technologies that enable machines to simulate human cognitive functions such as learning, problem-solving, and decision-making. But unlike conventional AI which depends on a strict set of rules, ML systems develop their own algorithmic strategies to solve problems by learning from datasets. This distinction marks a shift from a rule-based system to one that learns and evolves autonomously.
There are three main machine learning categories – supervised, unsupervised, and reinforced. The fourth on the list, semi-supervised, is defined as a combination of supervised and unsupervised machine learning.
Choosing the appropriate machine learning solution is crucial for effective model building, and should, naturally, be done before you begin any work on the project. Key factors to consider include the problem's nature, data characteristics (size, quality, and structure), and algorithm complexity.
Supervised learning is the process of modeling the relationship between the data inputs and the labels. It refers to the set of training examples (data inputs) where the desired output signals (labels) are known.
In other words, supervised machine learning utilizes labeled datasets to train algorithms that predict outcomes based on input data, with the goal of teaching a model from labeled training data to make predictions about future data. Some real-life use cases include image classification and forecasting market trends in financial analysis.
There are two major subcategories of supervised learning:
Some resources include a third category, ordinal regression or ordinal classification, which is considered a hybrid of the first two. This type of supervised machine learning is characterized by categories (like in classification) but with ordering information between the classes.
Unsupervised learning is the second largest machine learning category and it involves algorithms that learn patterns and structures from data that has not been labeled. The goal of unsupervised machine learning is to discover hidden structures in data, as opposed to predicting continuous or discrete target labels.
There are 3 techniques used for unsupervised machine learning:
Semi-supervised machine learning is, as its name suggests, the combination of unsupervised and unsupervised ML. It refers to the specific instance of supervised learning without human-annotated labels. Semi-supervised learning involves scenarios where only some training examples are labeled, and the idea behind this type of machine learning is to use the labeled dataset (via supervised learning) to label the unlabeled set.
Reinforcement learning is often considered the most challenging category of machine learning. Unlike supervised learning, reinforcement does not predict a specific outcome but is focused on learning a series of actions that result in a specific outcome.
Developing a system that enhances its performance through interactions with the environment, and as the program navigates its problem space, it receives feedback in terms of rewards and punishment. This type of machine learning is particularly popular in gaming.
Deep learning models can be any (or a combination) of the three machine learning types – supervised, unsupervised, or semi-supervised. They are advanced ML algorithms based on Artificial Neural Networks (ANN), built with multiple layers of interconnected neurons to emulate the way the human brain works.
When a deep learning model is assigned to classify text, images, video, or audio, the data moves through each layer of the model and it learns and improves its performance, similar to how the human brain evolves with age and experience. As such, deep learning models perform complex tasks and datasets better than other ML algorithms. However, the training takes longer since it requires millions and millions of pieces of data.
Deep learning algorithms are most commonly used for image and speech recognition, as well as Natural Language Processing (NLP). They are utilized by tech giants like Microsoft, Google, and Amazon to power their smart assistants, smart driving cars, and other next-generation systems.
This section lists the 11 key steps to help get started with the machine learning process:
The k-nearest neighbor (k-NN) is a pattern recognition model used for classification and regression tasks. The “k” represents a positive integer, usually small l in value.
Whether employed for classification or regression, the algorithm operates by identifying the 'k' closest training examples within a given space based on their feature values. These nearest neighbors serve as the basis for making predictions or assigning labels to new data points.
In classification, the majority class among the k neighbors determines the class label of the new instance, while in regression, the average or weighted average of the target values of the k neighbors is used to predict the target value for the new instance.
Decision tree learning is a predictive modeling technique used for visual representation in decision-making processes. They are used to find their application as predictive models when dealing with machine learning and data mining tasks.
The primary objective of decision tree learning is to construct a model capable of predicting the target value based on input variables. In this predictive model, data attributes, inferred through observation, are depicted as branches, while the conclusions regarding the target value are encapsulated within the leaves.
During the process of "learning" a decision tree, the source data is subdivided based on tests performed on attribute values. This subdivision is recurrently applied to each derived subset, forming branches in the decision tree. The recursion continues until each subset at a node corresponds to a consistent target value. This iterative process ultimately culminates in the creation of a decision tree model that effectively maps observations to conclusions about the target value.
Linear regression is a fundamental supervised learning algorithm employed to find a linear relationship between variables. Typically, one variable is considered dependent, while the other is independent.
For instance, in predicting a person's weight based on their height, weight would serve as the dependent variable, while height would be regarded as the independent variable. Through linear regression analysis, the algorithm seeks to identify and quantify the extent of influence that the independent variable(s) exert on the dependent variable.
Naïve Bayes is a machine learning algorithm used in scenarios involving large datasets where predictions are required. This method relies on conditional probability, specifically the likelihood of an event happening as a result of another event that already occurred. By leveraging these probabilities, Naïve Bayes efficiently categorizes and makes predictions based on patterns observed in the data, even when dealing with vast amounts of information.
The programming language directly impacts the efficiency, scalability, and ease of development. The choice depends on the language's ecosystem, available libraries, community support, and compatibility with existing systems.
Careful consideration of these factors ensures optimal selection, aligning with project requirements and personal expertise. But let’s look into the specific advantages and applications of each in a bit more detail.
Python tends to emerge as a top choice due to its rich ecosystem of frameworks and libraries, such as TensorFlow, PyTorch, and Keras. Its clear and concise syntax makes it highly readable and easy to understand, while its versatility allows it to function as both a scripting language and a general-purpose programming language.
Python's strength lies in its efficient data preprocessing and direct data manipulation, facilitating seamless workflow in machine learning projects. Additionally, the sci-kit-learn library, a cornerstone of Python's ML ecosystem, leverages existing packages like NumPy, SciPy, and Matplotlib, streamlining the development process.
Java is a prevalent language in enterprise programming, attracting front-end desktop application developers who are also engaged in machine learning projects within the enterprise domain. While it may not be a beginner’s top choice, Java is favored by individuals with a background in Java development seeking to apply their expertise to machine learning tasks.
Several machine learning libraries available in Java further bolster its popularity in the field:
Java is used for machine learning applications across industries, particularly in network security contexts such as cyber attack and fraud detection scenarios.
C++ is popular within domains like game development and robotics, where AI plays a crucial role. Developers working on applications such as robot locomotion often prefer C++ due to its efficiency and control over system resources. This language is especially favored by embedded computing hardware developers and electronics engineers, leveraging their proficiency to craft high-performance machine learning solutions.
C++’s appeal in the field is enhanced by its robust machine learning libraries, including mlpack, Dlib, and Shark, offering scalability, a wide array of algorithms, and modularity for streamlined development.
