At Rentech, models had to meet four principles(S-C-S-R), says Mr Frey. These were (and maybe still are):
- Simplicity – “don’t make it more complicated than it needs to be”;
- Commonality – “make it as broad as possible”;
- Stability – “models you have to readjust constantly probably aren’t as good as ones that stand the test of time”; and
- Rationality – “it can’t just be statistically valid”. You have to employ reason to identify a statistically significant but spurious pattern.
His website: http://www.ams.sunysb.edu/~frey/

我曾经一度期望QT挽救NOKIA的。
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ZZ —— August 3, 2011 @1:13 pm