[tahoe-dev] Tahoe-LAFS is widely misunderstood

[Shawn Willden]

On Wed, Feb 2, 2011 at 4:56 PM, Greg Troxel <gdt at ir.bbn.com> wrote:
>
> For 1-of-4, and 50% reliability, you have a 1/16 odds of losing.
> For 10-of-40, you win if any 10 are up; my head is too foggy to do the
> math but it seems lossage is much less likely than 1/16.
>

What, you can't evaluate 1 - 847660528 p^10 + 23118014400 p^11 -
307276941400 p^12 +
 2647309033600 p^13 - 16592954835600 p^14 + 80531140802112 p^15 -
 314574768758250 p^16 + 1015098413472000 p^17 -
 2756274164358000 p^18 + 6382950696408000 p^19 -
 12733986639333960 p^20 + 22050193314864000 p^21 -
 33325860350874000 p^22 + 44137259862696000 p^23 -
 51362108947363500 p^24 + 52594799562100224 p^25 -
 47411177489874000 p^26 + 37598406549704000 p^27 -
 26184604561401000 p^28 + 15967381365936000 p^29 -
 8489324426222640 p^30 + 3912131071992000 p^31 -
 1550404217451375 p^32 + 522929485728000 p^33 -
 148035185298000 p^34 + 34513346058048 p^35 - 6452815769400 p^36 +
 930135606400 p^37 - 97034823600 p^38 + 6520465600 p^39 -
 211915132 p^40 for p=.5 in your head?

It's 0.00034, which is 183 times smaller than 1/16.

-- 
Shawn
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