TC rounding

Hi everyone,

So, I'm practicing my card counting at home, dealing out 5 hands (one being "me" with chips) plus the dealer. I'm using 6D, NS, H17, DAS, respiting to 4 hands--rules that my local casino uses.

As I'm counting I'm also trying to calculate the TC, but I began to wonder at what point does one round up or down to a whole number? Or do some of you also use numbers like TC = 1.5 (and then adjust your bet accordingly)?

Let's say after the first hand the RC = +3. There are essentially 6 decks left, so TC = +0.5. At this point would you round up to 1 and then alter your bet? Or, would you wait until the TC is >= 1.0 before changing your bet? Or, do some of you have your own idiosyncratic methods for dealing with this?

p.s. it's actually kind of eerie how often the 'dealer' still wins even with a high TC!

Flooring.

For example, if the RC is 3 and there are 6 decks left, the TC is 0.

If the RC is 3 and there are 2 decks left, the TC is 1.

If the RC is -4 and there are 6 decks left, the TC is -1.

So, if your ramp has you increasing your bet at TC=1, then you don't increase your bet until the *floored* TC=1.

Quote: theoriemeister

Hi everyone,

So, I'm practicing my card counting at home, dealing out 5 hands (one being "me" with chips) plus the dealer. I'm using 6D, NS, H17, DAS, respiting to 4 hands--rules that my local casino uses.

As I'm counting I'm also trying to calculate the TC, but I began to wonder at what point does one round up or down to a whole number? Or do some of you also use numbers like TC = 1.5 (and then adjust your bet accordingly)?

Let's say after the first hand the RC = +3. There are essentially 6 decks left, so TC = +0.5. At this point would you round up to 1 and then alter your bet? Or, would you wait until the TC is >= 1.0 before changing your bet? Or, do some of you have your own idiosyncratic methods for dealing with this?

p.s. it's actually kind of eerie how often the 'dealer' still wins even with a high TC!

The two common methods are rounding and flooring, rounding being rounding up .5 and above and down .4 and below, while flooring being dropping everything after the decimal. It really isn't going to make much difference either way, except at + 0.5 situation. You don't want to round that up because at + 0.5 you are likely still playing a negative EV situation, while +1 is just about even or positive EV, depending on the rules. So if you round that +0.5 up to +1 and increase your wager you are increasing wager on a situation that is really still negative.

Don't be fooled about the higher TC situation. A lot of newer players think that means they are going to win more. That is really not the case. Win/loss/tie percentage don't change all that much, even in higher counts. What does change is that you receive more blackjacks and your double downs, particularly the hard 9's, 10, 11's double downs win slightly more often, so even though your win and lose about the same number of hands as before, you actually win a little more money because of the increased blackjacks @ 3/2 payout and increased successful double downs. (It mostly the blackjacks).

Thanks Call & kewlj.

I've heard of rounding, of course, just not in a gambling context. I've also never heard of 'flooring' but it makes sense. Interesting that I've not come across those terms in either Wong or Schlesinger (unless I missed it).

No problem. It was a good question. Check out Don S's BJA3, page 190. He says that "the methodology of choice for both reckoning the true count and for subsequent use of indices is flooring."

I'm a noob compared to KJ - and ESPECIALLY compared to Don S. So, I defer to their knowledge and experience.

Ah, I purchased a cheap copy of the 2nd edition!

I'd recommend buying the third edition. I don't have the earlier editions, but my understanding is that the third contains some significant additions as well as some changes to the tables in chapter 10 (perhaps others too).

You can get it on Amazon for about $23.

Quote: kewlj

while flooring being dropping everything after the decimal.

Dropping everything after the decimal is truncating, or always approaching zero.

Flooring is rounding down, always. This is different than truncating with negative numbers: -1.2 becomes -2.

Quote: Dieter

Dropping everything after the decimal is truncating, or always approaching zero.

Flooring is rounding down, always. This is different than truncating with negative numbers: -1.2 becomes -2.

Thread hijacked, sorry, just temporary.
Why no Avatar there, there's nothing, blank, nada?
There was one, I remember, then you just picked a blank space?
Sly devil...

Quote: TwoFeathersATL

Why no Avatar there, there's nothing, blank, nada?

There didn't used to be an avatar there before the redesign... I just picked a picture that looked like my avatar used to.

I may hide messages in it, from time to time.

Quote: theoriemeister

...Let's say after the first hand the RC = +3. There are essentially 6 decks left, so TC = +0.5. At this point would you round up to 1 and then alter your bet? Or, would you wait until the TC is >= 1.0 before changing your bet? Or, do some of you have your own idiosyncratic methods for dealing with this?

p.s. it's actually kind of eerie how often the 'dealer' still wins even with a high TC!

1) In the game you described why would a TC +0.5 (or TC +1 for that matter) change your bet? You need a TC +2 before you have any kind of advantage... Remember your rules and the initial house edge. At a S17 game you could up your bet at TC +1, but the HE on the game you mentioned is something like .64%, requiring a TC of +2 before you have any player edge.

2) As KewlJ said you don't win more often, for the most part =p. It can be quite frustrating to count, get a great count, then watch as the dealer hand is the one that gets all the 20's and blackjacks. It balances out though, but trust me when I tell you that you will doubt this (and if counting works) at some point. We all go through that losing streak where it just seems impossible to beat the game. This is where your statistics/tracking information will come in handy, and you can re-analyze your game to improve.

3) Both of these ideas are covered in my articles =).

4) Verbiage: The terms you're hearing thrown around originated because of programming. In common programming languages there are functions called CEIL, FLOOR, and TRUNCATE.

CEIL (short for Ceiling) - Always round up to the next whole number / integer. Ex: 1.1 = 2, 1.9 = 2.
FLOOR - Always round down to the next whole number / integer. Ex: 1.1 = 1, 1.9 = 1.
TRUNCATE - Always DROP everything after a decimal and only take the original whole number. Ex: 1.1 = 1, 1.9 = 1, -1.3 = -1.

Quote: Romes

1) In the game you described why would a TC +0.5 (or TC +1 for that matter) change your bet? You need a TC +2 before you have any kind of advantage... Remember your rules and the initial house edge. At a S17 game you could up your bet at TC +1, but the HE on the game you mentioned is something like .64%, requiring a TC of +2 before you have any player edge.

2) As KewlJ said you don't win more often, for the most part =p. It can be quite frustrating to count, get a great count, then watch as the dealer hand is the one that gets all the 20's and blackjacks. It balances out though, but trust me when I tell you that you will doubt this (and if counting works) at some point. We all go through that losing streak where it just seems impossible to beat the game. This is where your statistics/tracking information will come in handy, and you can re-analyze your game to improve.

3) Both of these ideas are covered in my articles =).

4) Verbiage: The terms you're hearing thrown around originated because of programming. In common programming languages there are functions called CEIL, FLOOR, and TRUNCATE.

CEIL (short for Ceiling) - Always round up to the next whole number / integer. Ex: 1.1 = 2, 1.9 = 2.
FLOOR - Always round down to the next whole number / integer. Ex: 1.1 = 1, 1.9 = 1.
TRUNCATE - Always DROP everything after a decimal and only take the original whole number. Ex: 1.1 = 1, 1.9 = 1, -1.3 = -1.

thanks, Rome. i learn new thing from u.

there is another question on baccarat's banker's advantage, for not hijacking the thread, can u go to' other game' to answer for me? you are always the expert. i will trust your answer for sure.

Quote: kewlj

The two common methods are rounding and flooring, rounding being rounding up .5 and above and down .4 and below, while flooring being dropping everything after the decimal. It really isn't going to make much difference either way, except at + 0.5 situation. You don't want to round that up because at + 0.5 you are likely still playing a negative EV situation, while +1 is just about even or positive EV, depending on the rules. So if you round that +0.5 up to +1 and increase your wager you are increasing wager on a situation that is really still negative.

Don't be fooled about the higher TC situation. A lot of newer players think that means they are going to win more. That is really not the case. Win/loss/tie percentage don't change all that much, even in higher counts. What does change is that you receive more blackjacks and your double downs, particularly the hard 9's, 10, 11's double downs win slightly more often, so even though your win and lose about the same number of hands as before, you actually win a little more money because of the increased blackjacks @ 3/2 payout and increased successful double downs. (It mostly the blackjacks).

Note a huge issue, but kewlj gave the definition of truncating, not for flooring.

FLOORING is when you always ROUND DOWN if there is a decimal:

0.9 -> 0
0.5 -> 0
0.1 -> 0
3.5 -> 3
5.75 -> 5
-0.5 -> -1
-1.5 -> -2
-7.9 -> -8

TRUNCATING is when you drop off the decimal:

0.9 -> 0
0.5 -> 0
1.5 -> 1
-2.3 -> -2
-0.2 -> 0
-0.9 -> 0
-5.7 -> -5


ROUNDING is when you round up when a decimal is 0.5 or greater, and round down when it is less than 0.5 (ie: 0.4999).


IMO, you should FLOOR your TC to an integer (non-decimal) number.

Thanks, RS.

I was wondering what to do with negative TCs.

And speaking of negative TCs, some of the advice I've read is that one should stop playing (bathroom break, phone call, seek a new table, etc.) when the TC reaches -2. If you're going to floor the TC so that anything less than -1 is going to be considered -2, that seems to suggest that one could spend quite a bit of time not playing, since it's common to encounter counts of -1 or less. Or, am I wrong about this?

You're right. Well sort of. It really depends. If it's the very beginning of the shoe and you're at -2, then yeah, GET OUT!! If you only have a few rounds to go before the shoe is over, just tough it out and keep playing. I believe it's in Don Schlesinger's BJA3, where he writes an excellent chapter on wonging. The chapter is primarily on wonging INTO a shoe, but, you can use a similar methodology for wonging out. Generally though, I wouldn't wong out until it's a TRUE TC -2. Meaning if it's -1.5 [and I round to -2], I keep playing. But once it hits or surpasses -2.0 [without rounding] then I'll start looking for something else to do.

If you're playing a single or double deck game, you pretty much gotta play through all the bad negative counts.