[Leo99]

I apologize if I should have waited for Mason to reply first.

I believe the units for the SD are $/session-hour.
Time of the session is taken into consideration by the equation so it's not critical. Number of hands is not part of the equation. As long as your session times are fairly consistent (from the same normal distribution) they're ok. In other words, Mason's example is fine. If you threw in a 5 minute session where you won or lost a lot of money it would skew the calculation. Mason only deals with money won or lost per session-hour.

If you averaged 15 hands per hour over all 10 sessions in the example: 83.11$/15 session-hour = 5.5 $/hand If we assume a $2 BB then 15BB/100hands = (15x2BB)/(100hands/15hands/hour) = $4.5 $/hand which seems about in the right ballpark.

I don't understand Mason's statement when he says that for most poker games of any size expect a higher SD. Since the calculation ignores the stakes, the SD should be proportional to the stakes. The SD needs to be normalized by the BB in order to compare the SD in a low limit game to the SD in a high limit game.