Once again, Kristopher Magnusson has combined is computer programming and statistical knowledge to help illustrate statistical concepts. His latest interactive tool allows students to view the t-curve for different degrees for freedom. Additionally, students can view error rates associated with different degrees of freedom.
Note that the critical region is one-tailed with alpha set at .05. If you cursor around the critical region, you can set the alpha to .025 to better illustrate a two-tailed test (in terms of the critical region at which we declare significance).
|Error rates when n < 30|
|Error rates when n > 30|
This isn't the first time Kristopher's interactive tools have been featured on this blog! He has also created websites dedicated to explaining effect size, correlation, and other statistical concepts.