Re: TIOBE Programming Community Index - update

[Paul.Jansen@tiobe.com]

Hi Martin,

Thanks again for your critical view on the TPC index.

Let me first stress that I am not biased as you are suggesting in your
review. I don't care about Ada being in 1st, 5th or 34th position. This
has nothing to do with our portfolio, because we adjust our portfolio
based on the TPC index and not the other way around. What we are trying
to do is to measure programming popularity with as simple rules as
possible in an objective way.

A while ago the language ABC (predecessor of Python) had a high score.
This was mainly due to the TV channel ABC and not because of ABC's
raising popularity. That's why we excluded "tv" and later on "channel".
For ABC the difference is 26,000 hits versus 886 hits! That's what I
call a difference (2934.5%)!

Now let me give you a brief course on statistics. If we add the
"missing" 17.4% to Ada's ratings this will become 0.540% * 1.174 =
0.634%. Now Ada is passing Fortran, wow! But... Fortran misses also
14.3%, so Fortran's ratings will become 0.600 * 1.143 = 0.686%. In
other words, the "-tv -channel" addition has no effect on the position
of Ada whatsoever! To be honest, I think most staticians will laugh
about your conclusion. It is a beginner's mistake.

I agree with you that we exclude now also legitimate pages with "-tv
-channel". But these are more or less equally distributed over all
languages. They hardly influence the ratings of languages because all
languages suffer from it more or less to the same degree. Only
languages which have a high amount of false positives are corrected in
this way.

Finally, there is indeed a bug in Google with exclusions. I have
submitted this already to Google.com, but apparently this has not been
fixed yet. 

Looking forward to your next review!

Regards,

Paul