Statistics

The field of statistics is concerned with collecting, analyzing, interpreting, and presenting data. Learn statistics and probability for free, in simple and easy steps starting from basic to advanced concepts.

mediator moderator variable
Statistics

Mediating vs Moderating Variables

Mediating variables explain how an independent variable predicts an outcome, outlining the causal mechanism. Moderating variables change the strength or direction of a relationship between...

Reviewed by Olivia Guy-Evans, MSc

moderating variable
Statistics

Moderating Variable In Statistics

Reviewed by Olivia Guy-Evans, MSc

mediator variable
Statistics

Mediating Variable In Statistics

Reviewed by Olivia Guy-Evans, MSc

anova calculator
Statistics

P Value Calculator From F Ratio (ANOVA)

Reviewed by Olivia Guy-Evans, MSc

chi squared equation
Statistics

P-Value Calculator for Chi-Square

Reviewed by Olivia Guy-Evans, MSc

Explore Statistics

t test formula

Statistics

P Value Calculator from T Score

Reviewed by Olivia Guy-Evans, MSc

Illustration of 3 people surrounding a larger computer screen displaying graphs and charts. One person is holding a giant magnifying glass

Statistics

Exploratory Data Analysis

Reviewed by Olivia Guy-Evans, MSc

Businessman holding pencil at big complete checklist with tick marks

Statistics

What Is Face Validity?

Reviewed by Saul McLeod, PhD

criterion validity

Statistics

Criterion Validity: Definition & Examples

Reviewed by Saul McLeod, PhD

convergent validity

Statistics

Convergent Validity: Definition and Examples

Reviewed by Saul McLeod, PhD

content validity

Statistics

Content Validity: Definition & Examples

Reviewed by Saul McLeod, PhD

construct validity

Statistics

Construct Validity In Psychology Research

Reviewed by Saul McLeod, PhD

concurrent validity

Statistics

Concurrent Validity In Psychology

Reviewed by Saul McLeod, PhD

one way ind anova

Statistics

What Is An ANOVA Test In Statistics: Analysis Of Variance

Reviewed by Saul McLeod, PhD

box whisker plot

Statistics

Reading a Box and Whisker Plot

Reviewed by Olivia Guy-Evans, MSc

sampling distribution

Statistics

What is the Central Limit Theorem in Statistics?

Reviewed by Olivia Guy-Evans, MSc

Chi Square Test of Independence

Statistics

Chi-Square (Χ²) Test & How To Calculate Formula Equation

Reviewed by Saul McLeod, PhD

confidence interval

Statistics

Confidence Intervals: Examples, Formula & Interpretation

Reviewed by Saul McLeod, PhD

cohen d

Statistics

What Does Effect Size Tell You?

Reviewed by Olivia Guy-Evans, MSc

Kurtosis

Statistics

What Is Kurtosis in Statistics?

Reviewed by Olivia Guy-Evans, MSc

bell curve

Statistics

Introduction to the Normal Distribution (Bell Curve)

Reviewed by Olivia Guy-Evans, MSc

Probability and statistical significance in ab testing. Statistical significance in a b experiments

Statistics

Understanding P-Values and Statistical Significance

Reviewed by Olivia Guy-Evans, MSc

sampling distribution

Statistics

Sampling Distribution In Statistics

Reviewed by Olivia Guy-Evans, MSc

Standard error formula

Statistics

Standard Error In Statistics: What It Is, Why It Matters, & How to Calculate

Reviewed by Saul McLeod, PhD

type 1 and 2 errors

Statistics

Type 1 and Type 2 Errors in Statistics

Reviewed by Saul McLeod, PhD

z score

Statistics

Z-Score [standard Score]

Reviewed by Olivia Guy-Evans, MSc

z score table

Statistics

How to Use the Z-Score Table (Standard Normal Table)

Reviewed by Olivia Guy-Evans, MSc