I was thinking about this today and wondered whether it can ever be positive expectation to raise peole all in with a hand like 78s, especially against medium stacked players?

Say if a player in a .50c/$1 game of Texas Hold 'Em No Limit makes a $4 raise from mid to late position and you are on the BB. He has a remaining stack of $16.

If the player was prepared to make the initial raise with AK, AQ, AJ, AA, KK, QQ, JJ, TT, 99, 88 and only prepared to call an all in with AK, AA, KK and QQ.

You are placing $19 into a $6.50 pot, so if they fold you are gaining $6.50 and this should happen when they have:

16 x AQ
16 x AJ
6 x JJ
6 x TT
6 x 99
6 x 88

Gives 56/90 times you will make $6.50 profit.

Of the remaining 34 times when you are called you will have the following expectation:

4 x AKs (38% underdog)
12 x AKo (41% underdog)
6 x AA (22% underdog)
6 x KK (22% unerdog)
6 x QQ (21% underdog)

This gives you an average epectation to win 0.29% of the time.

This gives 10/34 times = +$21.50
24/34 times = -$19

This means of 90 hands:

58 x +6.50 = + 377
10 x +21.5 = + 215
24 x -19 = - 456

Gives a total of + $136
Or 136/90 = + $1.5 per hand.

Added to this would be the advertising factor of encouraging large stacks to call your all ins with less than their usual standards.

Any thoughts?

Interesting, though one obvious gap in the logic is that pretty soon the hands that you have them folding they would start calling with as your image would be shot.

Irexes,

At which point you apply the principle of using your table image to your advantage and tighten up on your requirements and find that your KK is now being called by 88.

Indeed, but the process of identifying the change in your image and switching gears would likely cost you more than you made from the approach in the long run as a lot of the equity you make is from people folding hands they are prepared to make reasonable raises with in response to a reraise allin. In practice you would be lucky to get away with it once or twice before you were called and lost your stack, wiping out the benefit at a stroke.

You are not going to jeapordise your whole stack. That is why I would only do it against players with a smaller stack than myself. If you have a stack of $100 and there are 3 opponents at the table with $20. You may use the play twice without showing cards and make $13. Then if you get called the 3rd time you will probably be a 30% chance to lose $20.

However if you have already made this play twice and not been called you are quite happy to let the 3rd opportunity pass as people are more likely to call you anyway. Conversely if having used this play twice you are now dealt AA or KK when a shortstack makes a raise and you go all in they probably will now call you.