Bootstrapping is a resampling method that involves taking repeated samples (called ‘bootstrap samples’) from a dataset with replacement. It is used to estimate the distribution of a statistic and to calculate confidence intervals and significance tests. Here is the basic procedure: Draw a Sample: Randomly select n observations from the…
Naive Bayes is a linear classifier using Bayes Theorem and strong independence condition among features. Given a data set with n features represented by Naive Bayes states the probability of output: Y from features F_i is, Bayes theorem states that: Logistic regression is a linear classification method that learns the probability…
Naive Bayes is a very popular Supervised Classification algorithm. This algorithm is called “Naive” because it makes a naive assumption that each feature is independent of other features. It is near to impossible to find such data sets in real life. Bayes’ theorem is the base for Naive Bayes Algorithm….
Logistic Regression is a supervised classification algorithm that is used to predict the probability of a categorical dependent variable using a given set of independent variables. It is a predictive analysis algorithm and based on the concept of probability. The most common use of logistic regression models is in binary classification problems. Some…
Gradient Descent is an optimization algorithm used to find the values of the parameters of any function that minimizes the cost function. The average difference of the squares of all the predicted values of y and the actual values of y is called a Cost Function. It is also called…
Linear regression is a supervised machine learning algorithm used for modeling the relationship between a dependent variable and one or more independent variables by fitting a linear equation. I would like to say it is the starting point of anyone’s ML journey! Linear regression is the simplest and most widely…
There are the five major assumptions: 1. Linear relationship: There should be a linear and additive relationship between the dependent (Y) variable and the independent (X –> x1,x2,x3,…) variable(s). A linear relationship suggests that a change in response Y due to one unit change in x1 is constant, regardless of…
A confidence interval is a range of values we are fairly sure our true value lies in. It is calculated from the sample data and gives an interval estimate, as opposed to a point estimate. The confidence level, often expressed as a percentage (e.g., 95% or 99%), quantifies the level…
In the world of data science, statistical tests play a crucial role in drawing meaningful insights from data, making informed decisions, and validating hypotheses. Let’s explore five essential statistical tests: the Z-test, t-test, chi-squared test, ANOVA, and the lesser-known but powerful Fisher’s Exact Test. 1. Z-test: Unleash the Power of…
Hypothesis testing is a method statisticians use to make decisions or inferences about populations based on sample data. Hypothesis testing is a core concept in statistics that allows us to make informed decisions based on data. It’s a structured, methodical way to put our claims to the test, demanding evidence…