This collection of Analysis Tools can assist students and researchers with questions about study desgin, data analysis, and probability. Topics include sample size, power, survival, binomial probabilities, interaction, Fisher's exact test, one and two sample tests, and more.
This presentation on data analysis addresses observational studies and randomized controlled trials in two different sections. Types of studies are defined and examples of each study is given to emphasize the differences. Factors and variables are also discussed.
This site describes numerous methods of nonprobability sampling, including accidental, haphazard or convenience sampling and the many types of purposive methods.
Visual ANOVA is a simple little program that lets you put all this theory we've been describing into a simple visual whole. It assumes that you've read the Meanings and Intuitions section and have have understood the the general ideas at least. Even if your understanding of the previous section is incomplete at this time, it is worth playing with Visual ANOVA since that may clear up the big picture of ANOVA for you.
This applet simulates rolling dice and displays the outcomes in a histogram. Students can choose to roll 1, 2, 6, or 9 dice either 1, 10, 20, or 100 times. The outcome studied is the sum of the dice and a red line is drawn on the histogram to show expected number of occurences of each outcome.