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Dr. Kuan-Man Xu from the NASA Langley Reserach Center writes, "A new method is proposed to compare statistical differences between summary histograms, which are the histograms summed over a large ensemble of individual histograms. It consists of choosing a distance statistic for measuring the difference between summary histograms and using a bootstrap procedure to calculate the statistical significance level. Bootstrapping is an approach to statistical inference that makes few assumptions about the underlying probability distribution that describes the data. Three distance statistics are compared in this study. They are the Euclidean distance, the Jeffries-Matusita distance and the Kuiper distance. "

This presentation was given by Aneta Siemiginowska at the 4th International X-ray Astronomy School (2005), held at the Harvard-Smithsonian Center for Astrophysics in Cambridge, MA. 

Free statistical calculators online.  Our basic statistical calculators will help you in common tasks you might encounter and deal mostly with simple distributions. 

This textbook from VassarStats introduces various statistical topics and contains interactive components. Topics include: Measurement Principles; Distributions; Correlation; Regression; Partial Correlation; Rank-Order Correlation; Statistical Significance; Sampling Distributions; Hypothsis Tests; Probability; Chi-Square; Fisher's Exact Test; t-Distribution; t-test; Mann-Whitney Test; Wilcoxon Signed-Rank Test; Analysis of Variance; F-Distribution; Kruskal-Wallis Test; Friedman Test; Analysis of Covariance. Several calculators and generators include: Binomial Probability; Normal Probability; Binomial Sampling Distribution; Chi-Square Sampling Distribution.

Using the Fisher r-to-z transformation, this page will calculate a value of z that can be applied to assess the significance of the difference between two correlation coefficients, r_a and r_b, found in two independent samples. If r_a is greater than r_b, the resulting value of z will have a positive sign; if r_a is smaller than r_b, the sign of z will be negative.

For a table of frequency data cross-classified according to two categorical variables, X and Y, each of which has two levels or subcategories, this page will calculate the Phi coefficient of association; perform a chi-square test of association, if the sample size is not too small; and perform the Fisher exact probability test, if the sample size is not too large. For intermediate values of n, the chi-square and Fisher tests will both be performed.

This page will compute the t-test for either correlated or independent samples. One may copy and paste data in or type the data in individually.

...statisticians are the new sexy vampires, only even more pasty. A quote by American playwright, columnist, and humorist Paul M. Rudnick (1957 - ) from his November 19, 2012 essay "A Date with Nate" in "The New Yorker". The essay arose after the correct prediction of the winner of the presidential race in all 50 states in 2012 by statistician Nate Silver

A joke to teach the meaning of type I error by University of Texas at El Paso professor of Mathematical Sciences, Lawrence Mark Lesser (1964-) and Ohio State Unviersity PRofessor of Statistics Dennis K. Pearl (1951-).

A song to teach about Benford's Law for the probability distribution of first digits in real data. The lyrics are copyright by Lawrence Mark Lesser as a parody of Harry Nilsson's "One" made popular in 1969 by "Three Dog Night". "One is the Likeliest Number" was first published in the Spring 2011 issue of "Teaching Statistics". Free for use in non-profit education settings. Musical accompaniment realization and vocals are by Joshua Lintz from University of Texas at El Paso.