This PowerPoint presentation explains the two-sample t-test and t-interval, notation used, how to calculate the p-value, and standard errors based on variances. The original presentation is available for downloading.

...the most misleading assumptions are the ones you don't even know you're making is a quote by English author Douglas Noel Adams (1952-2001) that can be used in teaching the importance of understanding the assumptions being made that underlie statistical inference. The quote is from the 1990 book "Last Chance to See" that was co-written with Mark Carwardine. It is part of a passage that Adams...

Indeed, the laws of chance are just as necessary as the causal laws themselves. is a quote of quantum physicist David J. Bohm (1917- 1992). The quote appears on page 23 of his 1957 book "Causality and Chance in Modern Physics". The quote also appears in "Statistically Speaking: A dictionary of quotations" compiled by Carl Gaither and Alma Cavazos-Gaither.

I know there are some polls out there saying this man has a 32% approval rating. But guys like us, we don't pay attention to the polls. We know that polls are just a collection of statistics that reflect what people are thinking in reality. And reality has a well-known liberal bias. is a quote by American political satirist Stephen Tyrone Colbert (1964 - ). The quote is from a performance on...