Statistical Tools

What Statistical Calculators do you have at your website?

There is a calculator often assessed by users on conditional power calculations, and three other tabs currently contain seven other calculators. Hyperlinks provided here to all the pages and tabs may help the user get to these pages a little easier than through the drop-down menu on smaller devices.

Under the other sample size tab, we have calculators on early phase single sample clinical trials with a survival endpoint, on the Gehan two-stage design, on the Cochran-Armitage trend test, and on the sample size for logistic regression. In the trial enrollment tab, there are calculators assessing the influence of large strata or sites in clinical trials and on estimating clinical trial enrollment eligible subgroups in oncology.  Computations for observational data include the sample size for matched case-control and cohort studies.

The calculations themselves can be worked out in a few hours to a day. However there is a need to dig out the appropriate reference, maybe pay for it, read and figure out the results and write code to calculate and check the results – all of which could take a little time and effort.

How can we reach you?

I welcome any questions or comments. You can reach me at 551-233-6768 or via e-mail at

What other content is at your site?

We have write-ups on topics in quantitative science and other odds and ends at this page. We have financial advice offerings described at this page and details on graphical tools here.

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Deep thoughts by webmaster on characteristic functions from graduate school notes (left panel) and the fiercely handsome webmaster himself (right panel).