Regardless of whether PageRank is "bad math" (the author being the arbiter of what's bad), it was never about being formally anal, it was about solving a problem -- making search much, much better than the then-competition.<p>PageRank solves the problem with flying colors. There is nothing wrong about having hidden constants that you tweak until you get the results you want. The alternative would be to, instead of coding what has become Google, attempt to find a more general solution. Maybe you'll find it. Maybe. And if you do, by the time you have, someone else will have come and made Google instead of you. And for what? Mathematical purity? Phobia of constants?<p>I suppose the author also feels much of physics is also bad, since it's riddled with constants upon constants, all of which are "ticking time bombs": <a href="http://en.wikipedia.org/wiki/Physical_constant" rel="nofollow">http://en.wikipedia.org/wiki/Physical_constant</a>
The math in the original 1998 PageRank paper might not be mathematically 100% sound, but why would they need that in the first place? Do you really think you need a formal analysis before you build something? This is not academia, you know - if you need a formal proof of everything you do, you'd never get anything done.<p>Besides, the paper you're referring to is 13 years old. Why drag it up now?
"But π=3.14159265358979 is a time bomb! Sooner or later it will fail you when it’s not accurate enough anymore."<p>Well, actually for almost everything humans do, this will never, ever fail you. In fact, I can't think of a single thing this will fail for outside of physics research or formal mathematics.
> But π=3.14159265358979 is a time bomb! Sooner or later it will fail you when it’s not accurate enough anymore.<p>If you know the exact diameter of the sun, and calculate the circumference with 3.14159265358979 as an estimate for pi, then your error will be about 10 microns. Using a 14 digit estimate of pi, is never going to be a timebomb for any practical task. If the earth was round to 14 significant digits the highest mountains would tower 10 nanometers above the deepest valley.