Bernoulli Distribution - Complete Guide
Introduction A Bernoulli trial or Bernoulli experiment is a random experiment with exactly two mutually exclusive …
3 min ReadIntroduction A Bernoulli trial or Bernoulli experiment is a random experiment with exactly two mutually exclusive …
3 min ReadIntroduction Binomial distribution is one of the most important discrete distributions in statistics. It models the …
5 min Read
Introduction to Exponential Distribution The exponential distribution is a continuous probability distribution used to …
10 min Read
Introduction to Gamma Distribution The gamma distribution is a versatile continuous probability distribution used to …
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Introduction The geometric distribution is used to model situations where we are interested in finding the probability …
7 min Read
Hypergeometric Experiment A hypergeometric experiment is an experiment which satisfies each of the following conditions: …
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Introduction to Log-Normal Distribution The log-normal distribution is a continuous probability distribution of a random …
10 min Read
Introduction The negative binomial distribution is based on an experiment which satisfies the following three …
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Introduction to Normal Distribution The normal distribution, also known as the Gaussian distribution, is one of the most …
9 min Read
Poisson Distribution The Poisson distribution is one of the most important discrete probability distributions in …
9 min Read
Introduction to Uniform Distribution The uniform distribution is one of the simplest probability distributions where all …
8 min Read
Introduction to Weibull Distribution The Weibull distribution is one of the most widely used continuous probability …
8 min Read
Introduction to Hypothesis Testing Hypothesis testing is a statistical method for making decisions about populations …
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Advanced statistics extends beyond introductory methods to handle complex real-world scenarios. When assumptions are …
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Central Moments Overview Central moments are statistical measures calculated around the mean (or any fixed point) rather …
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Coefficient of Variation (CV) expresses standard deviation as a percentage of the mean. It’s dimensionless, making …
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While hypothesis testing asks “Is there a significant difference?”, confidence intervals ask …
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Correlation measures how two variables move together; regression predicts one variable from another. These tools help …
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Deciles Overview Deciles divide a dataset into 10 equal parts, with 9 dividing points: D₁, D₂, …, D₉. Each decile …
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Descriptive statistics is the foundation of data analysis. It involves methods to collect, organize, summarize, and …
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Statistical significance (p-value < 0.05) tells you an effect exists; effect size tells you how big it is. Large …
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Empirical Rule Overview The empirical rule, also known as the 68-95-99.7 rule, states that for a normal (bell-shaped) …
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Five-Number Summary Overview The five-number summary is a set of five statistics that provides a compact description of …
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The geometric mean is the nth root of the product of n values. It’s particularly useful for data representing …
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The harmonic mean is the reciprocal of the arithmetic mean of the reciprocals. It’s particularly useful for …
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The interquartile range (IQR) is the range of the middle 50% of data. It’s robust to outliers and useful for …
1 min Read
Kurtosis Overview Kurtosis measures the “tailedness” and peakedness of a distribution compared to a normal …
4 min Read
Mean Absolute Deviation (MAD) is the average absolute deviation from the mean. It’s more robust to outliers than …
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Mean, median, and mode are the three primary measures of central tendency. They each describe the “typical” …
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Octiles Overview Octiles divide a dataset into 8 equal parts, with 7 dividing points: O₁, O₂, …, O₇. Each octile …
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Outliers Overview Outliers are data points that deviate significantly from the typical pattern of a dataset. They can …
5 min Read
Percentiles Overview Percentiles divide data into 100 equal parts. The i-th percentile is the value below which i% of …
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Probability distributions describe how values in a dataset are spread across a range. They’re fundamental to …
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Quartile deviation (also called semi-interquartile range) is half the interquartile range. It represents the average …
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Quartiles Overview Quartiles are values that divide an arranged dataset into four equal parts. They consist of three …
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Every statistical study begins with a fundamental question: How do we choose who to study? Sampling is the process of …
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Skewness Overview Skewness measures the asymmetry of a distribution. It indicates whether data is symmetrically …
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Summary Statistics Overview Summary statistics provide a comprehensive overview of a dataset by summarizing key …
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Variance and standard deviation measure how spread out data is around the mean. Variance is measured in squared units, …
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Confidence interval for difference in means when variances are unknown and equal Let $x_1, x_2, \cdots, x_{n_1}$ be a …
2 min ReadBeta Type I Distribution A continuous random variable $X$ is said to have a beta type I distribution with parameters …
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Assignment Problem The assignment problem is a special case of transportation problem. Suppose there are $n$ jobs to be …
3 min ReadBayes’ Theorem One of the important uses of conditional probability is to find out the inverse probability. If an …
2 min ReadBayes’ Theorem One of the important uses of conditional probability is to find out the inverse probability. If an …
2 min ReadDefinition of Beta Type I Distribution A continuous random variable $X$ is said to have a beta type I distribution with …
3 min ReadBeta Type II Distribution A continuous random variable $X$ is said to have a beta type II distribution with parameters …
3 min ReadBeta Type II Distribution A continuous random variable $X$ is said to have a beta type II distribution with parameters …
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Cauchy Distribution A continuous random variable $X$ is said to follow Cauchy distribution with parameters $\mu$ and …
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Cauchy Distribution A continuous random variable $X$ is said to follow Cauchy distribution with parameters $\mu$ and …
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Chebyshev’s Inequality Chebyshev’s Theorem If $g(x)$ is a non-negative function and $f(x)$ be p.m.f. or …
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Chebyshev’s Inequality Let $X$ be a random variable with mean $\mu$ and finite variance $\sigma^2$. Then for any …
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Testing variance or standard deviation In this tutorial we will discuss a method for testing a claim made about the …
2 min Read
Chi-square Test for the Variance In this tutorial we will discuss a method for testing a claim made about the population …
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Column Minima Method Step 1 Select the smallest cost in the first column of the transportation table. Let it be …
1 min ReadIntroduction Confidence interval can be used to estimate the population parameter with the help of an interval with some …
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Confidence Interval for Mean In this tutorial we will discuss some numerical examples to understand how to construct a …
3 min ReadConfidence Interval for the population mean when standard deviation is unknown This tutorial covers examples on …
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Introduction In this article we will discuss step by step procedure to construct a confidence interval for difference …
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CI for difference between two population means (variances are known) In this tutorial we will discuss some examples on …
3 min Read
Confidence interval for difference in means when variances are unknown and equal In this tutorial we will discuss step …
4 min Read
Confidence Interval for paired t-test Let $X_1, X_2, \cdots, X_n$ and $Y_1, Y_2, \cdots, Y_n$ be two dependent samples …
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Confidence Interval for paired t-test In this tutorial we will discuss how to determine confidence interval for the …
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Confidence Interval for Proportion In this tutorial we will discuss some numerical examples to understand how to …
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CI for difference between two population proportions In this tutorial we will discuss some examples on confidence …
6 min Read
Confidence Interval for ratio of variances Let $X_1, X_2, \cdots , X_{n_1}$ be a random sample of size $n_1$ from …
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Confidence Interval for ratio of variances In this tutorial we will discuss some examples on confidence interval for …
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Introduction Confidence interval can be used to estimate the population parameter with the help of an interval with some …
2 min Read
Introduction Confidence interval can be used to estimate the population parameter with the help of an interval with some …
2 min Read
CI for difference between two population proportions Let $X_1$ be the observed number of individuals possessing certain …
2 min Read
Introduction Confidence interval can be used to estimate the population parameter with the help of an interval with some …
2 min Read
Confidence Interval for Variance In this tutorial we will discuss some numerical examples to understand how to construct …
3 min Read
Continuous Uniform Distribution A random variable has a uniform distribution if each value of the random variable is …
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Example Find the expected value and variance of $X$ for the following probability distribution. $x$ 1 2 3 4 $P(X=x)$ …
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Testing equality of two variances Many times it is desirable to compare two variances rather than comparing two means. F …
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F test for two variances In this tutorial we will discuss some examples on F test for comparing two variances or …
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Hungarian Method to solve Assignment Problem For obtaining an optimal assignment, Hungarian method involves following …
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Karl Pearson’s Correlation Coefficient Let $(x_i, y_i), i=1,2, \cdots , n$ be $n$ pairs of observations then the …
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Laplace Distribution A continuous random variable $X$ is said to have a Laplace distribution (Double exponential …
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Least Cost Entry Method This method is also known as Matrix Minima Method. Step 1 Select the smallest cost in the cost …
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Normal approximation to Poisson distribution In this tutorial we will discuss some numerical examples on Poisson …
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North-West Corner Method The North-West cornet method starts at the northwest corner cell of the transportation problem …
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Paired $t$-test (Dependent Sample) Let $X_1, X_2, \cdots, X_n$ and $Y_1, Y_2, \cdots, Y_n$ be two dependent samples each …
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Paired $t$-test (Dependent Sample) In this tutorial we will discuss some numerical examples on paired t test. Example 1 …
7 min Read
Plus Four Confidence Interval for Proportion In this article we will discuss step by step examples to construct a plus …
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Plus Four CI for difference between two population proportions In this tutorial we will discuss some step by step …
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Introduction In this article we will discuss step by step procedure to construct a plus four confidence interval for …
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Plus Four CI for difference between two population proportions The plus four method produces more accurate confidence …
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Poisson approximation to binomial distribution Let $X$ be a binomially distributed random variable with number of trials …
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Row Minima Method Step 1 Select the smallest cost in the first row of the transportation table. Let it be $c_{1j}$. …
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Sample size to estimate mean The minimum sample size required to estimate the population mean $\mu$ is $$ …
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Sample size to estimate proportion The minimum sample size required to estimate the population proportion is $$ n …
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Spearman’s Rank correlation Coefficient Let $(x_1, y_1), (x_2, y_2), \cdots , (x_n, y_n)$ be the ranks of $n$ …
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p value of the test p-value of the test is the probability that the test statistic under null hypothesis will take on …
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One Sample t test for mean In this tutorial we will explain the six steps approach used in hypothesis testing to test …
2 min Read
One Sample $t$-Test for mean In this tutorial we will discuss some numerical examples on one sample t-test for testing …
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Two sample t test with unknown and equal variances In this tutorial we will discuss two sample t-test for testing …
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Two sample t test for means with unknown but equal variances In this tutorial we will discuss some numerical examples on …
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Two sample t test for means with unknown and unequal variances In this tutorial we will discuss two sample t test for …
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Two Sample $t$-Test (Independent Sample with Unequal Variances) In this tutorial we will discuss some numerical examples …
5 min Read
Testing Correlation Coefficient Let $(x_i, y_i), i=1,2,\cdots, n$ be a random sample of $n$ pairs of observations drawn …
2 min Read
Testing Significance of Linear Relationship A test of significance for a linear relationship between the variables $x$ …
6 min ReadTesting Correlation Coefficient Let $(X_i, Y_i), i=1,2,\cdots, n$ be a random sample of $n$ pairs of observations drawn …
2 min ReadTesting Correlation Coefficient In this tutorial we will discuss step by step solution of numerical problems on testing …
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Testing Homogeneity of Two Correlation Coefficient We wish to test the null hypothesis that the correlation $\rho_1$ …
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Testing Homogeneity of Two Correlation Coefficient In this tutorial we will discuss step by step solution to some …
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Transhipment Problem The transhipment problem is more general than that of regular transportation problem, where direct …
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Transportation Problem Transportation problem is a special class of linear programming problem that deals with …
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Travelling Salesman Problem Suppose a salesman wants to visit certain number of cities, say, $n$. Let $c_{ij}$ be the …
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UV Method For Finding Optimal Solution of TP Step 1 First, construct a transportation table entering the origin …
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Vogel’s Approximation Method (VAM) Vogel’s approximation method is an improved version of the least cost …
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p value of the test p-value of the test is the probability that the test statistic under null hypothesis will take on …
2 min Read
One sample Z test for mean In this tutorial we will explain the six steps approach used in hypothesis testing to test …
2 min Read
Z-test for testing population mean In this tutorial we will discuss some numerical examples on one sample z test for …
5 min Read
$Z$-Test for Proportion Let $X$ be the observed number of individuals possessing certain attributes (say, number of …
2 min Read
Z-Test for Proportion In this tutorial we will discuss some numerical examples on one sample Z test for testing …
4 min Read
Two sample Z test for means In this tutorial we will discuss two sample Z test for testing the difference between means …
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Two sample Z test for means In this tutorial we will discuss some numerical examples on two sample z test for testing …
6 min Read
Two sample proportion test Suppose we want to compare two distinct populations $A$ and $B$ with respect to possessions …
3 min Read
$Z$-Test for difference of Proportions In this tutorial we will discuss some numerical examples on two sample Z test for …
6 min Read
Continuous Uniform Distribution The continuous uniform distribution is the simplest probability distribution where all …
3 min Read
Laplace Distribution A continuous random variable $X$ is said to have a Laplace distribution, if its p.d.f. is given by …
1 min Read
Confidence interval for means (variances are unknown and unequal) Let $x_1, x_2, \cdots, x_{n_1}$ be a random sample of …
2 min Read
Sample size to test mean The minimum sample size required to test the hypothesis about the population mean $\mu$ is $$ …
1 min Read
CI for difference between two population means with unknown and unequal variances In this tutorial we will discuss step …
4 min Read
Normal Approximation to Binomial Distribution Let $X$ be a binomially distributed random variable with number of trials …
2 min Read