So far, we have seen how we can use deletion methods and imputation methods to handle missing values in a dataset. These univariate methods used for missing value imputation are simplistic ways of estimating the value and may not always provide an accurate picture. For example, let us say we have variables related to the…
Cross-validation (CV) is part 4 of our article on how to reduce overfitting. Its one of the techniques used to test the effectiveness of a machine learning model, it is also a resampling procedure used to evaluate a model if we have limited data. To perform CV we need to keep aside a sample/portion of the data which…
Machine learning models require a large amount of data in order to learn about a specific subject. This collection of data is called a dataset. When working with machine learning methods we typically need a few datasets for different purposes. We can rely on open-source datasets to initiate ML execution. There are mountains of data…
Ridge Regression is a Linear Regression model use to solve some of the problems of Ordinary Least Squares by imposing penalty on regression coefficients. What is Ridge Regression? We have seen Ordinary Least Squares. Suppose we have independent variable X and dependent variable Y. we can write and our Objective Function is Suppose we have…
This is another statistical method that’s commonly used for testing relationships between categorical variables. Therefore, it’s suited for categorical variables and binary targets only, and the variables should be non-negative and typically Boolean frequencies or counts. What it does is simply compare the observed distribution between various features in the dataset and the target variable….
There are four main test statistics you can use in a hypothesis test. Which one you use depends on which statistical test you run. Please refer to our earlier post to understand the terminologies of Hypothesis Testing. Hypothesis Test Test Statistic Z-Test Z-Score T-Test T-Score ANOVA F-statistic Chi-Square Test Chi-square statistic Different test statistics The calculated…
