# Data Presentation

• ### "Probability by Surprise" Applets

A collection of several applets related to probability.

• ### Probability Sampling

This website lists five different types of probability sampling, giving the advantages and disadvantages of each.

• ### ** Binomial Distribution

This JAVA applet is designed to give students practice in calculating basic probabilities using the binomial distribution. The applet gives students short problem descriptions that require a binomial probability to solve. The user is then prompted to follow a step by step process to find the probability. Users must answer a step correctly before the applet will allow them to move on to the next step. The page also gives further exercises that allow the user to think about binomial distributions more deeply and gives a link to a more detailed information about the binomial distribution.
• ### Likelihood Ratio Test

This site focuses on using the LRT to compare two competing models.
• ### Log-likelihood ratio

This site offers an involved definition of the likelihood ratio test with examples and formulas.
• ### The Beta Distribution

This applet allows the user to adjust a (1st shape) and b (2nd shape) parmaters of the Beta distribution with a slider or manual input. The applet allows the user to fix the x and or y axes. The user immediately sees how this affects the the shape of the graph as well as the variance and the expected value. This page was formerly located at http://www.stat.vt.edu/~sundar/java/applets/BetaDensityApplet.html
• ### Simple Linear Regression

This tutorial on Simple Linear Regression includes its definition, assumptions, and characteristics as well as related statistics and hypothesis test procedures. One section instructs users to perform simple linear regression in the WINKS software, but those without the software can still use the tutorial. An exercise is given at the end that can be done with any statistical software package.
• ### Chi Square Tests

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

This page gives a description of correlation, Pearson's r, Spearman's rho. There are some scatterplots illustrating the different values of r.