Statistics Tutorials

Introduction to Confidence Intervals

Understand the margin of error, the confidence level and how confidence intervals describe the variability of a samples.

Comparing Two Means

Understand how to see if there is a significant difference between two samples. Covers the concept of sampling error and the t-distribution.

The Standard Deviation

Variability is a fundamental concept in statistics. This tutorial covers the standard deviation and why measuring variability is so important.

Calculators

2 Sample t-test

Compares the means of two data-sets using the t-distribution.

1 Sample t-test

Compares the means of one data-set against a test mean using the t-distribution.

Percentiles from the t-Distribution

Calculates the percent of area under the student t distribution given a t-score and degrees of freedom.

Inverse t-Distribution

Calculates the critical value from the student t distribution given a proportion of area and degrees of freedom.

Standard Deviation

Computes the sample standard deviation and population standard deviation from a dataset.