Products Review

Non-parametric Statistics Without Tears by Felix Grant PDF 500KB - Scientific Computing World - May 2004
Software Review by John Ludbrook PDF 14KB
Clinical and Experimental Pharmacology and Physiology - May 2004

User Comments

"There are only a few applications that I can unequivocally acknowledge as truly outstanding. StatXact and LogXact together fall into this category.

Until these two software applications existed, there was little opportunity for a statistician or researcher to appropriately model certain data situations. Statisticians were acutely aware that one could not obtain correct statistical results – and at times could not produce any at all – when there were sparse or highly unbalanced data. Performing a χ2 test on cells of counts was impossible if a given cell or cells had no values, or if there was an extreme imbalance in the cell values. When modeling data using a maximum likelihood logistic model it was known that convergence could not be achieved if there was perfect prediction. The methods designed by Cyrus Mehta and Nitin Patel, the founders of Cytel, gave statisticians the means to accurately model such data.

I thoroughly agree that exact statistical methodology needs to be in the toolbox of every working statistician. And, without reservation, StatXact and LogXact are the leading software applications in the area."

Joseph M. Hilbe
Software Reviews Editor, The American StatisticiaGregory J. Stoddard, University of Utah

”I have found that Cytel Inc. has consistently produced the best statistical software on the market. In addition, their manuals contain the technical information statisticians need, while being easy to understand and clearly illustrated with examples. I own every product that they offer. . . . Just recently a medical journal reviewer insisted that my co-authors and I report medians instead of means on some variables with skewed distributions. At first this concerned me . . . I was not aware of a method to calculate a confidence interval on a median, so . . . I consulted the StatXact manual just in case a solution was there, and to my delight, I found that StatXact offered a confidence interval on the median. This allowed a far more intuitive presentation of the data to the reader than using a normality transformation, which has no intuitive appeal to the medical audience, or anyone else for that matter.“

Gregory J. Stoddard
University of Utah

”StatXact for Windows is the sort of package that biomedical investigators don't know they need until the acquire it. Indeed, it is only if investigators use their own experimental data to compare the outcome of tests that make use of the chi-square, t or F distributions, with the outcome of their exact, permutational counterparts that they can begin to perceive the inexactitude of the former.“

J. Ludbrook
Clinical and Experimental Pharmacology and Physiology

”As a statistician and as a user of StatXact for some time, I must tell you that I really admire this program with its fantastic range of exact statistical procedures. It is only to be hoped that more and more statisticians get to know this wonderful statistical tool.“

Professor, Dr. Leo
Knusel Institut fur Statistik Ludwig-Maximilians-Universitat Munchen

”This Cytel Software constitutes the best statistical package that I have ever used. Please keep me informed of any updates & technical information.“

Dr. Robert E. Blake
REB-Consulting

”I have shown colleagues who are experts neither in statistics nor with computers how to use this package in a matter of 10 to 15 minutes. StatXact is already helping to revolutionize the way in which a variety of statistical problems are handled.“

Dr. John D. Emerson
Professor of Mathematics Middlebury College, Vermont

”StatXact proved to be an indispensable tool for efficient and effective problem solving in epidemiology and toxicology.“

Dr. E. Frohlich
Federal Office of Public Health and Environment Bern, Switzerland

”For my purposes, it's state of the art. There are some cases where we can't live without it.“

Paul Gibbs, Statistician

”With your software, I have a level of functionality in analysis of small data sets which was unheard of a few years ago. In fact, before the advent of your software, my predecessor wrote extremely complex basic programs to perform those calculations. It does everything I have needed to do.“

Graeme Tucker
Head Health Statistics Unit Department of Human Services Government of South Australia

”StatXact has two superior characteristics. One is the ease of use - StatXact is extremely easy to use and understand, which is a real draw. The second is that it's not only accurate, but it's accurate and effective even for small sample size, which makes it stand out from other statistical packages, none of which have as many options for exact tests. It's a terrific product.“

William (Bill) Fals-Stewart
Ph.D., Senior Research Scientist Research Institute on Addictions, University at Buffalo