Since I'm being harassed by a regular from this forum who I am convinced is a complete idiot, I would very much appreciate any comments on the validity of this post from the heads-up forum.
The thread containing this post was asking about the likelihood and frequency of downswings of various sizes while playing NLHE heads-up cash, with 20 buy-ins being a common example.
Obviously I gave up on my own (very misguided) attempts to approximate this problem, so all I've done here is plugged numbers into a formula provided by jason1990. Comments on both the validity of the formula itself, as well as comments on my application of the resulting math, would be greatly appreciated.
Thank you
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According to a formula generated in this thread:
http://forumserver.twoplustwo.com/sh...age=0&vc=1
If I managed to get the formula typed in right into excel (I'm fairly confident, since my output matched his numbers for the few examples he did run, but anything's possible, and I've screwed up far simpler things than transitioning a formula into excel)...
With a winrate of 8PTBB/100, and a std dev of 50PTBB/100, the chance of having a 20 buyin downswing in 50k hands is about 4.2%. Over 100k hands, it's 8.25%. Which (assuming the math is even close) basically means that one in twelve people will have a downswing that big in their first 100K hands. So yeah, that seems fairly common-ish. Of course, 100k hands is a *lot* of hands, so this probably shouldn't be a monthly occurence, but if you play enough, you could very easily see a swing that big multiple times.
And btw, this does depend HEAVILY on your actual variance. If the std. dev is increased to 75PTBB/100, the odds shoot through the roof, with an 57.3% chance of having a 20BI downswing over just 50k hands, and a 15.6% chance over just 10k hands. 75 does seem pretty high though, just based on the very few real std. devs I have heard.