Message Board : PNLH-1: Creating target SPRs

Nice work. 

One thing that I have noticed is that SPR's are proportional.

Here is what I mean by that. 

For example if we make a 10% of the smallest stack raise HU and get called our SPR will be 4.5.  So, if we make a 5% raise(half as large) we will get an SPR of ~9.  Since we are cutting the amount of money in half we double the resulting SPR. 

I just noticed this in passing so if (and am thinking as I do this) but this could be helpful for certain abouts.  This may not be that practical but could come in hand for easy calculations.  It works in reverse as well. 

For example, since a 10% raise equals an SPR of 4.5 then a 20% raise should equal an SPR of ~2.25.  

You can also take it as stack size dependent.

For example, a 2BB raise with 80BB stacks results in an SPR of 19.5. If you double the raise size to 4BB then the resulting SPR will be half. Thus, a 4BB raise will result in an SPR of ~10.  Carrying this example on a 3BB raise results in an SPR of 12.8 so a 6BB raise results in an SPR of ~6.5.

This is a good little trick that can help out. 

Your observation about the SPRs in proportion is a good one… it's one that I use while I play.

The formula thing I think can get dangerous, though… IMO it's a lot of precision in an idea that is, by its nature, imprecise. It's fine to do the formula if you realize garbage in-garbage out. That is… if you start with the wrong assumptions about your opponents or don't make a good estimate for your max/target SPRs, then your precise number will be precisely bad.

I think some people (mostly on other forums/places, not so much here) are taking SPR too literally… perhaps that's our fault for the way we introduced it in the book… but SPR is very much a "rule of thumb." The idea of commitment is a powerful one for planning hands, and SPR is designed to give you a general idea about when you're commited, when you're not, and if you'll get yourself into trouble by taking this action or that action.

I think it explains well why raising preflop with small cards in position can be good. Likewise, it explains well that once you put in that big preflop reraise, you're immediately in sink-or-swim mode if you flop something. And it explains why you can fool around with probing or information bets in some circumstances, but you can't in others.

But it's definitely not written in stone. Against some players I would fold top pair to a checkraise even if we started with an SPR of 2. And against other players, I'm more or less fine playing a top pair hand with an SPR of 13 because they'll rarely challenge me.

I treat SPR like a "sanity check" while I play. I don't use it, however, to decide whether to make it $15 or $17 to go preflop… or even $20 or $25 usually (though sometimes). Often other factors will take precedence. But at the same time, if I'm against a tough player or if I'm out of position in an uncertain situation, I'll definitely think about what SPRs will get me in the most trouble.