This page calculates the Poisson distribution that most closely fits an observed frequency distribution, as determined by the method of least squares. Users enter observed frequencies, and the page returns the fitted Poisson frequencies, the mean and variance of the observed distribution and the fitted Poisson distribution, and R-squared.
This page will perform the procedure for up to k=12 sample values of r, with a minimum of k=2. It will also perform a chi-square test for the homogeneity of the k values of r, with df=k-1. The several values of r can be regarded as coming from the same population only if the observed chi-square value proves the be non-significant.
This calculator returns the value of t for the difference between the means of two correlated samples, for sample sizes up to 10. Users are prompted for sample size as the page opens. It will also calculate various summary statistics for the two samples.
This chapter of the "Concepts and Applications of Inferential Statistics" online textbook describes in detail the Kruskal-Wallis test, it's formulas, variables, and procedures using an example involving wine-tasters.
As the page opens, you will be prompted to enter two sample size values, na and nb. If the samples are of different sizes, the larger of the two should be designated as sample A. If you are starting out with raw (unranked) data, the necessary rank- ordering will be performed automatically.
Beginning with a set of n paired values of Xa and Xb, this page will perform the necessary rank- ordering along with all other steps appropriate to the Wilcoxon test. As the page opens, you will be prompted to enter the number of paired values of Xa and Xb.
This page generates a Poisson distribution, as approximated by the Binomial. After clicking continue, users must enter the sample size (n>39) and probability of success (between 0.0 and 0.2, inclusive). A graph of the Poisson distribution with mean=np is shown as well as a table of the Poisson probabilities. Key Word: Poisson Calculator.
This page generates a histogram of a Poisson distribution and the associated table of probabilities. Upon opening the page, users will be prompted to enter the mean of the distribution (between 0.01 and 20.0, inclusive). Key Word: Poisson Calculator.
Illustrates the central limit theorem by allowing the user to increase the number of samples in increments of 100, 1000, or 10000.
Calculates the areas under the curve of the normal distribution falling to the left of -z, to the right of +z, and between -z and +z.