why do you think Purdue is much better than FSU and SB? And why do you think the SB is better than FSU?I think both Purdue PhD's are much better then FSU and SB.
According to US News SB's science departments are ranked fairly high, especially math is 23rd in US. Now the QF program is in Applied Math and I found some references that its decent. Also, according to The Financial Engineer ranking SB is above FSU by a large margin rank 15 vs 24. These are all indirect clues and kinda subjective but it's best I could find. By US News Purdue Stats phd is ranked 24 and Math phd is ranked 28. They are both very competitive. FSU math is ranked 73 lol That's probably why we haven't gotten offers Purdue yet. I was told the math department phd is specifically competitive to get in.
I see that you are just following rankings. I tend not to trust rankings that are mostly based on opinions.
Let me give you a piece of advice, try to find people who have gone through each of those programs and ask them about their experiences. Send them a quick email if you can (People in this forum are experts are using LinkedIn for this sort of thing). That's the only way you will get a real picture.
One more thing, you will get out of the PhD program as much as you want as long as you work at it. If your goal is academia, the school name might be important. However, if your goal is industry, it will mostly depend on you. Keep those things in mind when making a decision.