How-To Guides
Step-by-step guides that teach you how to perform calculations manually.
How to Calculate Covariance: Step-by-Step Guide
Learn to manually calculate covariance between two datasets (X and Y) for both population and sample. Includes formulas, a worked example, and common pitfalls.
Read guideHow to Calculate Binomial Probability: Step-by-Step Guide
Learn to manually calculate binomial probability step-by-step. Understand the formula, work through an example, and avoid common pitfalls.
Read guideHow to Calculate Poisson Probability: Step-by-Step Guide
Learn to manually calculate Poisson probability for rare events. Understand the formula, worked examples, common pitfalls, and when to use a calculator.
Read guideHow to Calculate a Confidence Interval for the Mean: Step-by-Step Guide
Learn to calculate a confidence interval for the mean by hand. Understand the formula, t-distribution, and interpret your results with a step-by-step example.
Read guideHow to Calculate Percentile Rank: Step-by-Step Guide
Learn to manually calculate percentile rank for any score in a dataset. Understand the formula, follow a worked example, and avoid common pitfalls.
Read guideHow to Calculate the Harmonic Mean: Step-by-Step Guide
Learn to manually calculate the harmonic mean of any dataset. Understand the formula, see a worked example, and compare it with other means.
Read guideHow to Find F-Distribution Values: A Manual Guide for ANOVA
Learn to manually find F critical values and estimate p-values using F-tables for ANOVA hypothesis testing. Understand the F-distribution's role.
Read guideHow to Calculate the Least-Squares Regression Line by Hand: A Step-by-Step Guide
Learn to manually calculate the least-squares regression line (slope, intercept) and R-squared for any dataset, with formulas, examples, and common pitfalls.
Read guideHow to Calculate Z-Score Probability: Step-by-Step Guide
Learn to manually convert Z-scores to probabilities and percentiles using a Z-table. Understand the formula, worked examples, and common pitfalls.
Read guideHow to Calculate the Interquartile Range (IQR) and Five-Number Summary: Step-by-Step Guide
Learn to manually calculate the Interquartile Range (IQR) and the five-number summary step-by-step. Understand Q1, Q2, Q3, and how to identify outliers.
Read guideHow to Calculate the Geometric Mean: Step-by-Step Guide
Learn to calculate the geometric mean manually with our step-by-step guide. Covers the nth root formula, log method, worked examples, and common pitfalls.
Read guideHow to Calculate Moving Average: Step-by-Step Guide
Learn to calculate the Moving Average by hand! Understand the formula, follow a worked example, and avoid common pitfalls for accurate results.
Read guideHow to Calculate Chi-Square (χ²) Test: Step-by-Step Guide
Learn to calculate the Chi-Square test by hand to determine if two categorical variables are independent. Includes formula, example, and interpretation.
Read guideHow to Calculate a Paired t-Test: Step-by-Step Guide
Learn to manually calculate a Paired t-Test to compare related means. Includes formula, worked example, common pitfalls, and interpretation guide.
Read guideHow to Calculate a Confidence Interval for the Population Mean: Step-by-Step Guide
Learn to manually calculate a confidence interval for a population mean using a sample. Understand the formula, t-distribution, and interpretation.
Read guideHow to Calculate Statistical Power (and Sample Size): Step-by-Step Guide
Learn to manually calculate statistical power and required sample size for hypothesis tests. Understand the formula, worked examples, and common pitfalls.
Read guideHow to Calculate Effect Size (Cohen's d): Step-by-Step Guide
Learn to calculate Cohen's d effect size by hand with this step-by-step guide. Understand the formula, worked examples, and common pitfalls.
Read guideHow to Calculate P-Value from Test Statistics: A Step-by-Step Guide to Hypothesis Testing
Learn to manually calculate p-values from z, t, and chi-square test statistics. Understand hypothesis testing with formulas, examples, and interpretation.
Read guideHow to Calculate P-Values for Z, T, and Chi-Square Tests: Step-by-Step Guide
Learn to manually calculate p-values from Z, T, and Chi-Square test statistics using distribution tables. Understand hypothesis testing step-by-step.
Read guideHow to Calculate Outliers Using the IQR Method: Step-by-Step Guide
Learn to manually calculate outliers using the Interquartile Range (IQR) method. Find Q1, Q3, IQR, and whisker bounds step-by-step.
Read guideHow to Calculate Square Roots and Nth Roots by Hand
Learn to calculate square roots, cube roots, and any nth root manually with step-by-step instructions, formulas, and examples. Understand the math behind roots!
Read guideHow to Calculate the F-Test for Comparing Variances: Step-by-Step Guide
Learn to manually calculate the F-test to compare variances of two groups. Understand the formula, worked example, and common pitfalls.
Read guideHow to Calculate Cronbach's Alpha: Step-by-Step Guide
Learn to calculate Cronbach's Alpha by hand! This guide breaks down the formula, provides a worked example, and explains how to interpret reliability scores for your research.
Read guideHow to Calculate the Trimmed Mean: Step-by-Step Guide
Learn to calculate the trimmed mean by hand. Remove extreme values from your dataset for a more robust average. Includes formula, example, and common pitfalls.
Read guideHow to Check Divisibility Rules: Step-by-Step Guide
Learn to manually check divisibility by 2 through 12. Master the rules with examples, understand common pitfalls, and know when to use a calculator.
Read guideHow to Calculate Set Operations by Hand: Union, Intersection, Difference, and Symmetric Difference
Learn to manually calculate set union, intersection, difference, and symmetric difference with formulas, examples, and common pitfalls.
Read guideHow to Calculate Proportions: Step-by-Step Guide
Learn to solve proportions and find missing values using cross-multiplication. Master the formula, see a worked example, and avoid common mistakes.
Read guideHow to Calculate with 2x2 Matrices: Determinant, Inverse, Addition, and Multiplication
Learn to manually calculate 2x2 matrix operations: addition, multiplication, determinant, and inverse. Includes formulas, examples, and pitfalls.
Read guideHow to Understand and Interpret Type I and Type II Errors: A Step-by-Step Guide
Learn Type I and Type II errors, alpha, beta, and statistical power with a clear, step-by-step guide and worked example. Understand their impact on decisions.
Read guideHow to Calculate the Mann-Whitney U Test: Step-by-Step Guide
Learn to manually calculate the Mann-Whitney U test, a non-parametric alternative to the t-test. Understand the formula, steps, and interpretation.
Read guide