CardSharp

Last time, I wrote that the play of the cards in holdem often times coveys very little information about the state of the hand.  This produces an interesting effect: since the available information at the end of the last betting round is usually very similar the information at the start of the next round, there is a general expectation on the part of the players that the last person to bet or raise last round will, if given the opportunity, bet first this round.  This concept is called the ‘betting lead’ and it’s important to understand both for the purposes of betting your hand correctly, and for interpreting other people’s bets.

The Mechanics Of How The Betting Lead Affects Play

Lets for a moment consider a hand that is heads-up.  There are two players – player A and player B.  Player A acts first.  Last betting round player A checked, player B bet, and A called so B has the betting lead .  For simplicity’s sake, we’ll make it a limit holdem game (although this idea applies equally if not more to NL).  Now, each player could have various goal if you will for this round of betting.  For simplicity’s sake we’ll simplify the possible goals into two options:

A player either wants to have money go in the pot this round, or they don’t.
We will also assume, at least temporarily, that player A will respect the betting lead and always check to B initially rather than leading out.

First, let’s notice a difference between the player expectations here – player B never expects to fold this street of play.  If he decided to stop betting, and player A respects the betting lead, player B will never have to fold.  This is our first major observation about the betting lead:

If you are in last absolute position, have the betting lead from the previous betting round, and your opponent(s) respect it, you can always adopt a line that insures you won’t have to fold on this betting round.

That’s important because there are situations where one player very much desires not to have to fold on a given street of play – for example when they hold a draw.  An easy way to ensure you get another card to to be in position and bet or raise and take the betting lead on the previous street of play.

Now, with two possible goals for each player, there are four possible ways this hand can play out assuming player A respects the betting lead.  If both want to get money into the pot, money will go in.  If player B wants to check, it will be checked around regardless of A’s desires.  If B wants to bet and A doesn’t want to raise, then of course A has to decide to call or not.  The important thing to observe here is that B always gets what he wants – if he wants money to go in, money goes in.  If he wants a check around, there’s a check around.  This leads to our second major observation about the betting lead:

When the player in position has the betting lead, and his opponent(s) respect it, the player in position always gets what he wants out of that round of betting in terms of money going in or not going in.

If you perform the same analysis again, but give player A the betting lead, you’ll find the situation more muddled.  Again assume that each player has the same two possible goals.    With the betting lead on player A, the result is that player who wants money to go in gets their desired result any time they run up against players who desire not to have money go in.  In other words, neither player has the ability to guarantee their desired result and the situation is surprisingly symmetrical.

The Betting Lead As A Source Of Positional Advantage

A few months back I wrote this an article on position in response to a search query on the subject.  While it’s a decent article certainly, and rather nicely parrots conventional wisdom on the subject of position, I now believe it to be wrong in at least one major respect.  I listed two advantages provided by position: an absence of risk and the availability of additional information.  Both those, however, are rather nebulous concepts .  I now believe that the ability to control whether money goes in the pot via manipulation of the betting lead when you are in position is the strongest single advantage of absolute position.  “Information” is a nice concept and all, but manipulating the betting lead gets money in the pot when you’re ahead and saves you money when you’re drawing.  That’s where the rubber meets the road in terms of positional advantage – it’s the mechanism that turns position into chips.  Strangely, I can’t recall seeing this fundamental concept in print before.

Setting The Bet Sizes

In big bet (pot limit or no limit) games, the betting lead often conveys another advantage.  It lets you determine the size of the bets.  For example suppose there’s a $50 pot, you’re first to act out of two players, and you have the betting lead.  If you want to exercise pot control, you have the option of underbetting the pot – say $25 or so.   This puts your opponent in a position where he has a difficult choice if he would have preferred more money went in.  He can raise, but the minimum raise to $50 may be bigger than he would have chosen had you checked to him, and furthermore doing so re-opens the betting.  Unless he holds the nuts or close to it he probably doesn’t want to do that.  The net effect is that if you hold the betting lead, most of the time your opponents will go along with your bet sizing as long as it’s not too far out of line.  As we’ll see in a forthcoming article on pot control, this can be very handy.

The Advantages Of Respecting The Betting Lead

With all this discussion of the betting lead providing an advantage to the in-position player, you might wonder why out-of-position players would choose to respect the betting lead.  There’s certainly nothing requiring them to do so – they always have the option of leading out even if they didn’t put in the last bet or raise on the previous round.  But when out of position it’s usually to your advantage to respect the betting lead anyways.  The reason is simply that if you want to take the lead, your in-position opponent who currently has the lead will usually bet often enough that you’re better off going for the check-raise.

This goes to further illustrate the nature of positional advantage.  The betting lead gives last position an innate advantage, but yet it’s still usually in the best interests of the early position player to respect the betting lead.  In other words,  the position advantage cannot be countered by any simple means. Something to chew on.

Reading Hands Via The Betting Lead

I want to take a little diversion here into the basics of a subject called “information theory”.  It was founded by a man by the name of Claud Shannon, an MIT educated engineer who also happens to be one of the patron saints of gambling theory.   Oddly enough, the topic of interest here is not his work on gambling, but rather his work on transmitting information via wires.  He made the following observation: if you have a wire, and there are symbols coming off that wire, an unexpected symbol carries much more information than an expected symbol.

That may sound kind of abstract, and indeed Shannon stated it in even more esoteric terms.  But it’s not really that difficult a concept.  Imagine a telegraph system.  The telegraph wire carries two “symbols” – the “dot” and the “dash”.  Now suppose the operator on the other end of the wire sends nothing but dots.  Does this convey any information to you?  Does it mean anything?  Of course not – since you already know what the next symbol is going to be, it doesn’t tell you anything. You could go out to lunch, come back, there’d still be nothing but dots and you would have missed nothing of interest.  The same would go for an operator who sends nothing but dashes.

But the guy who sends dots AND dashes, now his message means something.  You don’t know which is going to come next, and if you go out to lunch you won’t be able to accurately reconstruct what he sent while you were gone.  Those symbols, because they are unexpected, mean something.

Back to poker.  It’s expected that people will follow the betting lead.  So when they do, what does it mean?  Not much – expected symbols cary limited information.  But when someone does the unexpected and the betting lead changes (either because someone raisesd, the expected bettor declined to bet, or someone chose not to respect the betting lead) then that means a lot.  This is a fundamental concept in hand reading: the places in the hand where the betting lead changes are the key moments in analyzing the hand.  They’re the signposts that guide you in your attempt to deduce what your opponents are up to.  Some bets & checks are a lot more informative than others.