"Graham D Smith" <[EMAIL PROTECTED]> wrote in message
00c701bf3b2a$59f61d30$066c51c2@f19a">news:00c701bf3b2a$59f61d30$066c51c2@f19a...
> I agree with much of what has been said about the shortcomings of Excel.
> After all this strand of discussion was arose from problems with its
ranking
> procedure. However, I don't think that users should rely on Excel's
> statistical functions or analysis tools.
>
> Bob said;
> >Anybody can do statistic with Minitab, but you need a Ph.D. in statistics
> to (safely) do statistics with Excel. The LAST >people in the world who
> should beusing Excel for statistics are beginners.
Microsoft Excel's statistical accuracy is often called into question, and in
many instances the criticism is justified. But the problems are not limited
to Excel !!
However, we have recently been comparing Analyse-it (see
http://www.analyse-it.com/) our statistics software for Microsoft Excel
against competitor products. Our testing is based on the publically
available NIST datasets, and our testing includes most of the popular
packages like XlStat, WinStat, Minitab, SAS, SPSS and so on.
We were shocked by the results! We'll be publishing details on our web-site
soon, along with the datasets & results for all to see, but briefly:
* Excel's built-in statistical functions like STDEV(), VAR() and CORREL()
yeild inaccurate results in many cases. Most of the Excel add-ins use the
above functions so propagate these errors. Analyse-it does not use **ANY**
of Excels functions so is not affected.
* Even well established packages that are taken for granted like SPSS & SAS,
which were independently tested by the American Statistical Association, did
not perform well in many cases. In a few cases even Excel's results are more
accurate! You can read the reports online at
http://www.amstat.org/publications/tas/mccull.pdf and
http://www.amstat.org/publications/tas/mccull-1.pdf
* In our tests, Analyse-it has equal or better accuracy than SPSS, SAS and
the other Excel add-ins! No independent testing has been done on Minitab but
in our tests we found it to be as or less accurate than Analyse-it.
The problems arise from the use of inappropriate numerical algorithms.
Microsoft used some very unstable algorithms in Excel which has led to the
critisisms. Analyse-it uses numerically stable algorithms and produces
accurate results (many Excel add-ins use the same unstable algorithms as
Microsoft).
We will shortly be publishing the results of our testing on our web-site at
http://www.analyse-it.com/ In the meantime, I warn all users to be aware of
problems even in the supposedly accepted packages like SPSS. The above
papers show the problems are not limited just to Excel.
And of course, if you want to do any statistical analysis within Excel, then
download a free copy of Analyse-it from our web-site.
Regards,
_____________________________________
James Huntington
ANALYSE-IT SOFTWARE LTD
.............................................................
Analyse-it! powerful accurate statistical analysis for Microsoft Excel
Download a free no-obligation 14-day evaluation, and get more info at:
http://www.analyse-it.com
