# Measures of Spread

• ### Introduction to Biostatistics (Populations and Samples)

The third chapter of an online Introduction to Biostatistics course. Lecture notes are provided. Additionally, links for additional reading and exercises with solutions are provided.

• ### Regression/Correlation

The ninth chapter of an online Introduction to Biostatistics course. Lecture notes and links for futher reading are provided.
• ### Introduction to Biostatistics (Normal Distribution)

The fifth chapter of an online Introduction to Biostatistics course. Three sets of lecture notes are provided. Additionally, links for additional reading and exercises with solutions are provided. A link is also given for a related statistical applet on the normal distribution.

• ### Introduction to Biostatistics (Estimation)

The sixth chapter of an online Introduction to Biostatistics course. Three sets of lecture notes are provided (only the first one works). Additionally, links for additional reading and exercises with solutions are provided.

• ### introduction to Biostatistics (Bernoulli and Binomial Distributions)

This resource provides two sets of detailed notes on the Bernoulli and Binomial distributions. Additional readings, examples, exercises, and links to applets illustrating the respective distributions are also given.

• ### Introduction to Biostatistics

An online Introduction to Biostatistics course complete with lecture notes and links for futher reading, links to applets, and exercises with solutions given.
• ### Building a Probability Tree Applet

This applet simulates a probability tree diagram. Step 1: Click inside the appropriate box on the desired level to build the tree. Step 2: Click on "Set Probabilities" at the top. Step 3. When you enter the respective probabilities, you must hit the ENTER key after each one. Step 4: Once all of the probabilities have been set (they should be blue), click "Final Tree" Step 5: Click "Simulation".
• ### "Probability by Surprise" Applets

A collection of several applets related to probability.

• ### Variance and standard deviation

This source defines and explains variance and standard deviation.
• ### Basic Sample Stats Calculator

The page calculates summary statistics for any dataset. Users will be prompted for sample size when opening this page. The calculator returns mean, sum of X, sum of X^2, variance, standard deviation, and standard error. Key word: Descriptive statistics.