Useful tips for everyday
What is a weakly dependent time series? A (time) sequence of random variables is weakly dependent if distinct portions of the sequence have a covariance…
What is classification in decision tree? Decision tree builds classification or regression models in the form of a tree structure. It breaks down a dataset…
How is a confounding variable related to the cause and effect? A confounding variable, also called a confounder or confounding factor, is a third variable…
How is feature importance calculated in XGBoost? Importance is calculated for a single decision tree by the amount that each attribute split point improves the…
How do you test the null hypothesis? Hypothesis testing works by collecting data and measuring how likely the particular set of data is (assuming the…
How to do Bayesian regression in PyMC3 using MCMC? Bayesian Regression in PYMC3 using MCMC & Variational Inference. Conducting a Bayesian data analysis – e.g.…
What statistical test should be used to find whether there is a relationship between the rankings? A chi-square test is used when you want to…
Should PCA be done before train test split? If you apply PCA on the whole data (including the test data) before training the model, then…
What does a residuals vs leverage plot show? The Residuals vs. Leverage plots helps to identify influential data points on the model. outliers can be…
What is the difference between direct effect and total effect? In the simple figures above, the estimate of the total effect is the value of…