# Category Archives: Python

## Tensor Explained with Python Numpy Examples Tensors are a hot topic in the world of data science and machine learning. But what are tensors, and why are they so important? In this post, we will explain the concepts of Tensor using Python Numpy examples with the help of simple explanation. We will also discuss some of the ways that tensors can be used in data science and machine learning. When starting to learn deep learning, you must get a good understanding of the data structure namely tensor as it is used widely as the basic data structure in frameworks such as tensorflow, PyTorch, Keras etc. Stay tuned for more information on tensors! What are tensors, and why are …

Posted in Data Science, Deep Learning, Machine Learning, Python. Tagged with , , .

## Cohen Kappa Score Python Example: Machine Learning Cohen’s Kappa Score is a statistic used to measure the performance of machine learning classification models. In this blog post, we will discuss what Cohen’s Kappa Score is and Python code example representing how to calculate Kappa score using Python. We will also provide a code example so that you can see how it works! What is Cohen’s Kappa Score or Coefficient? Cohen’s Kappa Score, also known as the Kappa Coefficient, is a statistical measure of inter-rater agreement for categorical data. Cohen’s Kappa Coefficient is named after statistician Jacob Cohen, who developed the metric in 1960.   It is generally used in situations where there are two raters, but it …

Posted in Data Science, Machine Learning, Python. Tagged with , , .

## Accuracy, Precision, Recall & F1-Score – Python Examples Classification models are used in classification problems to predict the target class of the data sample. The classification model predicts the probability that each instance belongs to one class or another. It is important to evaluate the performance of the classifications model in order to reliably use these models in production for solving real-world problems. Performance measures in machine learning classification models are used to assess how well machine learning classification models perform in a given context. These performance metrics include accuracy, precision, recall, and F1-score. Because it helps us understand the strengths and limitations of these models when making predictions in new situations, model performance is essential for machine …

Posted in Data Science, Machine Learning, Python. Tagged with , , , .

## K-Fold Cross Validation – Python Example In this post, you will learn about K-fold Cross-Validation concepts with Python code examples. K-fold cross-validation is a data splitting technique that can be implemented with k > 1 folds. K-Fold Cross Validation is also known as k-cross, k-fold cross-validation, k-fold CV, and k-folds. The k-fold cross-validation technique can be implemented easily using Python with scikit learn (Sklearn) package which provides an easy way to calculate k-fold cross-validation models.  It is important to learn the concepts of cross-validation concepts in order to perform model tuning with the end goal to choose a model which has a high generalization performance. As a data scientist / machine learning Engineer, you must have a good …

Posted in Data Science, Machine Learning, Python. Tagged with , , , .

## Linear Regression Explained with Python Examples In this post, you will learn about concepts of linear regression along with Python Sklearn examples for training linear regression models. Linear regression belongs to class of parametric models and used to train supervised models.  The following topics are covered in this post: Introduction to linear regression Linear regression concepts / terminologies Linear regression python code example Introduction to Linear Regression Linear regression is a machine learning algorithm used to predict the value of continuous response variables. The predictive analytics problems that are solved using linear regression models are called supervised learning problems as it requires that the value of response/target variables must be present and used for training the models. Also, recall that …

Posted in Data Science, Machine Learning, Python. Tagged with , , , .

## Mean Squared Error or R-Squared – Which one to use? In this post, you will learn about the concepts of the mean-squared error (MSE) and R-squared, the difference between them, and which one to use when evaluating the linear regression models. You also learn Python examples to understand the concepts in a better manner What is Mean Squared Error (MSE)? The Mean squared error (MSE) represents the error of the estimator or predictive model created based on the given set of observations in the sample. Intuitively, the MSE is used to measure the quality of the model based on the predictions made on the entire training dataset vis-a-vis the true label/output value. In other words, it can be used to …

Posted in Data Science, Machine Learning, Python. Tagged with , , .

## Tensor Broadcasting Explained with Examples In this post, you will learn about the concepts of Tensor Broadcasting with the help of Python Numpy examples. Recall that Tensor is defined as the container of data (primarily numerical) most fundamental data structure used in Keras and Tensorflow. You may want to check out a related article on Tensor – Tensor explained with Python Numpy examples. Broadcasting of tensor is borrowed from Numpy broadcasting. Broadcasting is a technique used for performing arithmetic operations between Numpy arrays / Tensors having different shapes. In this technique, the following is done: As a first step, expand one or both arrays by copying elements appropriately so that after this transformation, the two tensors have the …

Posted in Data Science, Deep Learning, Machine Learning, Python. Tagged with , , , , .

## Statistics – Random Variables, Types & Python Examples Random variables are one of the most important concepts in statistics. In this blog post, we will discuss what they are, their different types, and how they are related to the probability distribution. We will also provide examples so that you can better understand this concept. As a data scientist, it is of utmost importance that you have a strong understanding of random variables and how to work with them. What is a random variable and what are some examples? A random variable is a variable that can take on random values. The key difference between a variable and a random variable is that the value of the random variable …

Posted in Data Science, Python, statistics. Tagged with , , .

## SVM Classifier using Sklearn: Code Examples In this post, you will learn about how to train an SVM Classifier using Scikit Learn or SKLearn implementation with the help of code examples/samples.  An SVM classifier, or support vector machine classifier, is a type of machine learning algorithm that can be used to analyze and classify data. A support vector machine is a supervised machine learning algorithm that can be used for both classification and regression tasks. The Support vector machine classifier works by finding the hyperplane that maximizes the margin between the two classes. The Support vector machine algorithm is also known as a max-margin classifier. Support vector machine is a powerful tool for machine learning and has been widely used …

Posted in Data Science, Machine Learning, Python. Tagged with , , .

## Autoregressive (AR) models with Python examples Autoregressive (AR) models are a subset of time series models, which can be used to predict future values based on previous observations. AR models use regression techniques and rely on autocorrelation in order to make accurate predictions. This blog post will provide Python code examples that demonstrate how you can implement an AR model for your own predictive analytics project. You will learn about the concepts of autoregressive (AR) models with the help of Python code examples. If you are starting on time-series forecasting, this would be a useful read. Note that time-series forecasting is one of the important areas of data science/machine learning.  For beginners, time-series forecasting is the process of using a model …

Posted in Data Science, Machine Learning, Python. Tagged with , , .

## Ridge Regression Concepts & Python example Ridge regression is a type of linear regression that penalizes ridge coefficients. This technique can be used to reduce the effects of multicollinearity in ridge regression, which may result from high correlations among predictors or between predictors and independent variables. In this tutorial, we will explain ridge regression with a Python example. What is Ridge Regression? Ridge regression is a type of linear regression technique that is used in machine learning to reduce the overfitting of linear models. Recall that Linear regression is a method of modeling data that represents relationships between a response variable and one or more predictor variables. Ridge regression is used when there are multiple variables that …

Posted in Data Science, Machine Learning, Python. Tagged with , , .

## Lasso Regression Explained with Python Example In this post, you will learn concepts of Lasso regression along with Python Sklearn examples. Lasso regression algorithm introduces penalty against model complexity (a large number of parameters) using regularization parameter. The other two similar forms of regularized linear regression are Ridge regression and Elasticnet regression which will be discussed in future posts. In this post, the following topics are discussed: What’s Lasso Regression? Lasso regression is a machine learning algorithm that can be used to perform linear regression while also reducing the number of features used in the model. Lasso stands for least absolute shrinkage and selection operator. Pay attention to the words, “least absolute shrinkage” and “selection”. We will …

Posted in Data Science, Machine Learning, Python. Tagged with , , , .

## Stochastic Gradient Descent Python Example In this post, you will learn the concepts of Stochastic Gradient Descent (SGD) using a Python example. Stochastic gradient descent is an optimization algorithm that is used to optimize the cost function while training machine learning models. The most popular algorithm such as gradient descent takes a long time to converge for large datasets. This is where the variant of gradient descent such as stochastic gradient descent comes into the picture. In order to demonstrate Stochastic gradient descent concepts, the Perceptron machine learning algorithm is used. Recall that Perceptron is also called a single-layer neural network. Before getting into details, let’s quickly understand the concepts of Perceptron and the underlying learning …

Posted in Data Science, Machine Learning, Python. Tagged with , , .

## How to deal with Class Imbalance in Python In this post, you will learn about how to deal with class imbalance by adjusting class weight while solving a machine learning classification problem. This will be illustrated using Sklearn Python code example. What is Class Imbalance? Class imbalance refers to a problem in machine learning where the classes in the data are not equally represented. For example, if there are 100 data points and 90 of them belong to Class A and 10 belong to Class B, then the classes are imbalanced. Class imbalance can lead to problems with training machine learning models because the models may be biased towards the more common class. If there are more examples …

Posted in Data Science, Machine Learning, Python. Tagged with , , , .

## K-Nearest Neighbors Explained with Python Examples In this post, you will learn about the K-nearest neighbors algorithm with Python Sklearn examples. K-nearest neighbors algorithm is used for solving both classification and regression machine learning problems.  Introduction to K-Nearest Neighbors (K-NN) K-nearest neighbors is a supervised machine learning algorithm for classification and regression. In both cases, the input consists of the k closest training examples in the feature space. The output depends on whether k-nearest neighbors are used for classification or regression. The main idea behind K-NN is to find the K nearest data points, or neighbors, to a given data point and then predict the label or value of the given data point based on the labels or values … 