10 Machine Learning Algorithms Every ML Engineer Should Know
Machine learning (ML) is a rapidly growing field with a wide variety of applications. ML engineers are responsible for developing and deploying ML models that can solve real-world problems.
To be successful as an ML engineer, it is important to have a strong understanding of the underlying machine learning algorithms. In this blog post, we will discuss 10 of the most important machine learning algorithms that every ML engineer should know.
1. Linear regression
Linear regression is a simple algorithm that can be used to predict a continuous value, such as the price of a house or the number of sales. The model is defined by a line that minimizes the sum of squared errors between the predicted values and the actual values.
How it works: Linear regression works by finding the line that best fits the data points. The line is defined by a slope and a y-intercept. The slope tells us how much the predicted value changes for every unit change in the independent variable. The y-intercept tells us the predicted value when the independent variable is zero.
Advantages:
- Linear regression is a simple algorithm that is easy to understand and implement.
- It is relatively efficient to train, even on large datasets.
- It can be used to predict a wide variety of continuous values.
Disadvantages:
- Linear regression can only be used to predict continuous values.
- It is not as accurate as some other machine learning algorithms, such as decision trees and neural networks.
2. Logistic regression
Logistic regression is a more complex algorithm that can be used to predict a categorical value, such as whether or not a customer will default on a loan. The model is defined by a sigmoid function that maps the predicted values to a probability.
How it works: Logistic regression works by finding the line that best separates the two classes. The line is defined by a slope and a y-intercept. The slope tells us how much the predicted probability changes for every unit change in the independent variable. The y-intercept tells us the predicted probability when the independent variable is zero.
Advantages:
- Logistic regression can be used to predict both continuous and categorical values.
- It is relatively efficient to train, even on large datasets.
- It is more accurate than linear regression for predicting categorical values.
Disadvantages:
- Logistic regression can be more difficult to understand and implement than linear regression.
- It is not as accurate as some other machine learning algorithms, such as decision trees and neural networks, for predicting continuous values.
3. Support vector machines (SVMs)
SVMs are a non-parametric model that can be used for both classification and regression tasks. The model finds the hyperplane that maximizes the margin between the two classes.
How it works: SVMs work by finding the line that best separates the two classes while also maximizing the distance between the line and the closest data points. The data points that are closest to the line are called the support vectors.
Advantages:
- SVMs are very accurate for both classification and regression tasks.
- They are relatively robust to noise and outliers.
- They can be used to solve a wide variety of problems.
Disadvantages:
- SVMs can be more difficult to understand and implement than other machine learning algorithms.
- They can be computationally expensive to train, especially on large datasets.
4. Decision trees
Decision trees are a tree-based model that predicts a value based on a set of rules. The rules are learned by recursively splitting the data into smaller and smaller subsets.
How it works: Decision trees work by asking a series of questions about the data. The questions are designed to split the data into smaller and smaller subsets until each subset contains only data points of the same class. The final prediction is made based on the class of the largest subset.
Advantages:
- Decision trees are easy to understand and interpret.
- They are relatively efficient to train, even on large datasets.
- They can be used to solve a wide variety of problems.
Disadvantages:
- Decision trees can be sensitive to noise and outliers.
- They can be overfitting, which means that they learn the training data too well and do not generalize well to new data.
5. Random forests
Random forests are an ensemble model that combines multiple decision trees to make more accurate predictions. The trees are trained on different subsets of the data, and the predictions are averaged to get the final prediction.
How it works: Random forests work by training multiple decision trees on different subsets of the data. The trees are trained using a random subset of the features, which helps to prevent overfitting. The predictions from the individual trees are then averaged to get the final prediction.
Advantages:
- Random forests are very accurate for both classification and regression tasks.
- They are relatively robust to noise and outliers.
- They are easy to understand and interpret.
Disadvantages:
- Random forests can be computationally expensive to train, especially on large datasets.
6. K-nearest neighbors (KNN)
KNN is a non-parametric model that predicts the label of a new data point based on the labels of its k nearest neighbors. The k nearest neighbors are the data points that are most similar to the new data point.
How it works: KNN works by finding the k data points that are most similar to the new data point. The labels of the k nearest neighbors are then used to predict the label of the new data point.
Advantages:
- KNN is very simple to understand and implement.
- It is relatively efficient to train, even on large datasets.
- It can be used to solve a wide variety of problems.
Disadvantages:
- KNN can be sensitive to noise and outliers.
- It can be computationally expensive to find the k nearest neighbors for a new data point, especially on large datasets.
7. Naive Bayes
Naive Bayes is a simple probabilistic model that assumes that the features of a data point are independent of each other. The model is defined by a probability distribution for each feature.
How it works: Naive Bayes works by assuming that the features of a data point are independent of each other. This means that the probability of a data point belonging to a particular class is the product of the probabilities of each feature belonging to that class.
Advantages:
- Naive Bayes is very simple to understand and implement.
- It is relatively efficient to train, even on large datasets.
- It can be used to solve a wide variety of problems.
Disadvantages:
- Naive Bayes can be inaccurate if the features of the data points are not independent.
8. Neural networks
Neural networks are a powerful model that can learn complex relationships between features and labels. Neural networks are made up of interconnected neurons, and each neuron learns to respond to a specific pattern of input.
How it works: Neural networks work by learning the weights of the connections between the neurons. The weights are adjusted during training so that the neural network can learn to predict the correct label for the data points.
Advantages:
- Neural networks can be very accurate for a wide variety of tasks.
- They can be used to solve problems that are not possible to solve with other machine learning algorithms.
Disadvantages:
- Neural networks can be difficult to understand and interpret.
- They can be computationally expensive to train, especially on large datasets.
9. Deep learning
Deep learning is a type of neural network that uses multiple layers of neurons to learn even more complex relationships. Deep learning models have been shown to be very successful in a variety of tasks, such as image classification and natural language processing.
How it works: Deep learning works by learning the weights of the connections between the neurons in multiple layers. The weights are adjusted during training so that the deep learning model can learn to predict the correct label for the data points.
Advantages:
- Deep learning models can be very accurate for a wide variety of tasks.
- They have been shown to be more accurate than other machine learning algorithms for many tasks.
Disadvantages:
- Deep learning models can be difficult to understand and interpret.
- They can be computationally expensive to train, especially on large datasets.
10. Ensemble learning
Ensemble learning is a technique that combines multiple machine learning algorithms to make more accurate predictions. Ensemble models are often more accurate than any single algorithm.
There are many different ways to combine machine learning algorithms, but some of the most common methods include:
- Bagging: Bagging is a technique that combines multiple copies of the same algorithm, each trained on a different bootstrap sample of the data.
- Boosting: Boosting is a technique that combines multiple algorithms, each of which is trained to correct the mistakes of the previous algorithm.
- Stacking: Stacking is a technique that combines multiple algorithms, each of which is trained to predict the output of the other algorithms.
The best ensemble learning method for a particular problem will depend on the data and the desired outcome.
Advantages:
- Ensemble models can be more accurate than any single algorithm.
- Ensemble models can be more robust to noise and outliers.
- Ensemble models can be more interpretable than single algorithms.
Disadvantages:
- Ensemble models can be more computationally expensive to train than single algorithms.
- Ensemble models can be more difficult to tune than single algorithms.
These ten algorithms are your passport to the captivating world of machine learning. By mastering them, you’ll gain a profound understanding of the mechanisms that drive AI solutions. Remember, the key to truly understanding these algorithms is hands-on practice. Apply them to real-world datasets, tweak parameters, and see the magic unfold as you unlock the potential to create intelligent systems that learn and evolve. With these essential tools in your arsenal, you’re well on your way to crafting remarkable AI innovations.