Hi, this is just a quick question that I hope is not too silly. Thanks.

I noticed the house edge provided by different sources differ somewhat, and the discrepancies apparently are not due to rounding off.

For example, for [ D6, H17, DAS, RSA ] Arnold Snyder's article (using Peter Griffin's Theory of Blackjack) gives 0.54, while it is 0.57 from some website.

(I just ordered my cv package a couple of days ago so haven't been able to run the sims myself)

The five sources I'm looking at are:
http://www.blackjackforumonline.com/content/Calculating_the_House_Edge_for_Any_Blackjack_Rules _Set.htm#rules
http://www.blackjackinfo.com/bjbse.p...rr=ns&peek=yes
http://www.card-counting.com/blackja...calculator.htm
http://www.svengaliblackjack.com/edgecalc.html
http://www.beatingbonuses.com/houseedge.htm

The last two are exactly the same.
(btw, for these last two, what does 'per unit wager' mean? I thought this house edge is assuming betting one unit at this very one hand at the top of the shoe....)

Please take a look at the attachment for the comparison. HouseEdge.pdf
One would expect the numbers across a row to be the same 9within rounding error), but they are not.