Harringtons M Zones

[Boothill]

This is how Harrington explains his zones of play based on your M.
From Harrington on Holdem Volume 2: The Endgame.
M is the ratio of a player's chipstack to the total of the blinds and antes.

The Green Zone : Your M is 20+ (20 or more times the SB + BB + antes)
This is where you want to spend as much of the tournament as possible. All styles of play are open to you. you can be conservative, aggressive, or super-aggressive, and switch back and forth among them as you wish, all moves are available. You can watch a raise and a reraise and come over the top of both players, and still have plenty of chips left for another move later in the hand. In the green zone you're a full- functional poker player, and it's worth taking some risks to stay here.

The Yellow Zone : Your M is 10-19
As you move from the green zone to the yellow zone you lose the ability to play conservative poker. The blinds are starting to catch you, so you have to loosen your play. You can be aggressive or super-aggressive but you have to start making moves with hands weaker than those a conservative player would elect to play. Oddly enough, however, certain hand types (small pairs and suited connectors) become less playable in the yellow zone (due to the lack of implied odds).

The Orange Zone : Your M is 6-9
In the orange zone, you lose the ability to make certain kinds of complex moves that require a reasonable stack size to succeed. Here's an example, a type of sandwich play. A loose middle position player raises 2-3 times the big blind. You know from past experience that he's probably trying a steal. But before you, another player sticks in a reraise. You realize that he probably knows what you know, and knows he doesn't need much of a hand to take the pot from the first bettor. If you have any kind of hand at all and a decent stack, you can come over the top of both players. The first player will probably lay his hand down, and if your raise is substantial and you have more chips to back it up, the second player will probably quit as well. But to execute this maneuver, you need a big stack relative to the pot. If you have to go all-in to make this play, the second bettor may be able to call you just based on pot odds, since he knows you can't do any further betting. In the orange zone, you have to play even more aggressively than in the yellow zone.

The Red Zone : Your M is 1-5
In the red zone you've lost any ability to make a bet other than an all-in bet. If you make a smaller bet, it consumes so much of your stack that you're pot committed anyway. So you might as well go all-in, since it gives you the best chance of winning the pot with your first bet. Of course when your M is lower than 3, your all-in bet will probably not be enough to drive other players out of the pot. The combination of your weak situation plus the attractive odds will usually result in at least one caller.

The Dead Zone : Your M is less than 1 times (SB + BB + antes)
In the dead zone you appear to be alive but your not... you're a poker wraith, just a gnat to be swatted. Your only move left is all-in. And when you make it they'll call just to get rid of you. Never allow yourself to get this low by having your chips blinded away, as you'd have been much better off making a stand earlier with marginal cards. Decent players arrive here only by accident, like after losing an all-in against a slightly smaller stack. It's essential here to be the first into the pot, so you must make a move before the blinds arrive. by moving first, some hands that would call you because of your tiny stack will fold because of the danger of someone coming over the top behind them. The need to move first is so great that your cards really don't matter anymore.


More About M

You should be estimating your M before every hand, and also maintain an idea of the M's of the other players. As you move down through the lower zones - yellow, then orange, then red - your M becomes a key piece of information about your hand, every bit as important as the cards themselves.

Another way of looking at M is to see it as a measure of just how likely you are to get dealt a better hand in a better situation later, and still have a reasonable amount of money left. There are two dangers in being too tight in the middle zones. First: your stack can get blinded away. And Second: You may wait for a good hand and get it at a time when it's no longer useful to you (like with raises and reraises ahead of you).

For example, a tight player drifts through the orange zone, passing chances to make a stand with a somewhat marginal hand. When his M finally gets down to 2, his dream scenario occurs. He picks up AA, someone in front of him moves all-in and he calls... winning and doubling up. Great... but now his M is still just 5! He's still in the red zone, and still needs to double up again very soon. If he'd made a riskier move when his M was somewhat higher, like 7, a double up would have taken him to 14, well into the yellow zone, and bought him valuable time.

Boot

[Chad Rea]

"M" is not something that is just helpful in tournament play...it is an absolute reqiurement to understand...and it's very easy to calculate this quickly.

As taken from "Harrington On Hold'em Volume 2: The Endgame"
M is the ratio of a player's chipstack to the total of the blinds and antes.

chipstack / (sb+bb+antes) = M *** (this formula is for full tables)

When the tournament switches to short table play, you have to make one small adjustment totake into account that the blinds hit you more often, also known as "Effective M".

Effective M = (Basic M) times (Players Left/10)

CR

[Chad Rea]

Here's an interesting article written by Dene Tribe on Two Plus Two Internet Magazine:

Arnold Snyder is the author who first published the blind off theory in evaluating tournament structure and my system uses his theory in a different way. Arnold Snyder and many poker players today believe that an evaluation of your chip stack compared to how many times you can pay the Big Blind is the preferred method of determining the style of play required. In his book Poker Tournament Formula, Snyder advises players they should begin to alter play when there chip stack decreases to less than 30 Big Blinds (BB) unless antes are present, then he recommends 40BB..

I disagree with the big blind method and based my system on an evaluation of the M, which is a more accurate calculation. In this article, I will show you why you should be calculating your M at all times and using this in determining the style of play you should be pursuing. Dan Harrington introduced the zone concept in HOH volume 2 and this is the basis of my system. If your M is 20 or greater you have a competitive stack. But, as your M decreases below 20, you need to begin Short Stack play. If you go as low as 5M, most moves at a pot are all-in.

Do I really need to calculate my M or is the Big Blind good enough? If there are no antes present then basing your decisions on your chip stack as a multiple of the big blind works. Once the antes kick in you need to be using your M since the Big Blind method can become inaccurate. Study the two simple examples below.

Example #1 Resorts Atlantic City tournament Level 4 SB 200 BB 400 Ante 75 16,000 Chips full 10 player table

Snyder's BB calculation 16000/400 = 40 BB Using Snyder's System 40 Big Blinds is a competitive stack and no strategy adjustments are necessary until we have less than that

Harrington's M calculation 16000/1350=12M In this case the 12M is well below the threshold of 20M and we are now very aware of the critical situation. If we do not act fast we will soon be in the all-in zone.

Example #2 What If we increase the chip stack to 24000? Of course all that has happened is we have increased everything by 33%, but I think most players think 60 BB is a good stack, but 18M not so good.

Snyder's BB Calculation 24000/400=60 BB

Harrington's M calculation 24000/1350 = 18M

Always Calculate Your M If you always use the M, your calculation will always be accurate. If you use the BB, you will sometimes run into problems when the antes kick in. Another advantage to using the M instead of the Big Blind is that it accounts for the number of players remaining at the table. For example, with only 5 players posting antes instead of 10, the M will change and you can adjust accordingly. In summary, the BB measurement is normally accurate. But, the M is always accurate. If you are using the BB, such as in the examples above, you may not realize you are getting short stacked until it is to late.

CR