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The Gini coefficient is a statistical measure of inequality, most commonly used to evaluate income or wealth distribution. It is named after the Italian statistician Corrado Gini, who introduced the index in 1912. The Gini coefficient ranges from 0 to 1, where 0 represents perfect equality (everyone has the same income or wealth), and 1…

The multinomial distribution is a multivariate extension of the binomial distribution, which models the probability of observing k successes and (n-k) failures in n independent Bernoulli trials. In other words, it models the probability distribution of multiple categories or outcomes in a single experiment or trial. This concept is widely used in various statistical analyses,…

The Exponential Distribution is a continuous probability distribution used to model the time between events in a Poisson Process. It is characterized by its memoryless property, meaning the probability of an event occurring in a small time interval is independent of the time elapsed since the last event. In this article, we will explore the…

The t-distribution is a probability distribution that is commonly used in statistical inference when the sample size is small and the population standard deviation is unknown. It is a bell-shaped distribution that is similar to the standard normal distribution, but it has heavier tails, which implies that it is more sensitive to outliers. The t-distribution…

Stratified sampling is a statistical method used to select a sample from a population in a way that the different subgroups or strata within the population are proportionally represented in the sample. This technique is particularly useful when we want to ensure that the sample has the same distribution of certain characteristics as the population….