which illustrious 18 indices are right?

i keep finding different indices from different sources, and im not sure which to believe! for example, if you compare play bj like the pros (blackwood) to (Dead link: http://www.dicedealer.com/chapter_11.htm) (last chart/graphic) you will find EIGHT, i repeat 8 differences! thats insane! 44% of the ill 18 are dif? not to mention if you compare other sources, your bound to find ones that are off by perhaps 2 tc points.. and yes, i am aware of the difference between "= to or greater than" and "greater than" (in this thread, lets treat all indices as "equal to or greater than" which is what most books do.. so do is the 16 vs 10 zero or +1? is the TT vs 6 +4 or +5? is 13 vs 2 zero or -1? etc.. i seriously dont get how people claim how it doesnt matter if indices are off, or that they and the true count are insanely rounded.. how can all of blackjack be pure math, yet the true count and indices can be so vague and still hold accuracy? can som1 shed light on this?

SilentBob420BMFJ said:

so do is the 16 vs 10 zero or +1?

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Technically you can stand with an RC of +1. This play is really close so neither 0 or +1 is correct. The right answer is somewhere in between. That is why some sources differ.

SilentBob420BMFJ said:

is the TT vs 6 +4 or +5? is 13 vs 2 zero or -1?

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It doesn’t matter. You won’t notice any difference in actual play.

SilentBob420BMFJ said:

how can all of blackjack be pure math, yet the true count and indices can be so vague and still hold accuracy? can som1 shed light on this?

Click to expand...

Because indices are only an estimation of the correct play. They are only based on the cards that you count so they do not have complete information about the remaining cards. There are also many different ways to calculate indices (EV maximizine, risk averse, CE adjusted, rounded, floored, truncated, etc.) so there is bound to be small, and sometimes large, differences between these methods. Since the TC is also an estimation (estimating the decks played, estimating the TC, estimating your advantage, etc.) you are making an estimate based on the estimate of another estimate. How much more vague could you be?

-Sonny-

this is the very reason why rounded indices work SO well with very little loss compared to precise indices. additionally since the I-18 only adds a small advantage to your game, slight modification and variation in these numbers matters little.

playing insurance right is worth as much as the I18 combined!

Sonny said:

Technically you can stand with an RC of +1. This play is really close so neither 0 or +1 is correct. The right answer is somewhere in between. That is why some sources differ.



It doesn’t matter. You won’t notice any difference in actual play.



Because indices are only an estimation of the correct play. They are only based on the cards that you count so they do not have complete information about the remaining cards. There are also many different ways to calculate indices (EV maximizine, risk averse, CE adjusted, rounded, floored, truncated, etc.) so there is bound to be small, and sometimes large, differences between these methods. Since the TC is also an estimation (estimating the decks played, estimating the TC, estimating your advantage, etc.) you are making an estimate based on the estimate of another estimate. How much more vague could you be?

-Sonny-

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do you know what most indexes are based off of? i would guess EV maximization.. also, you say that its based only off the cards that came out, but thats the same thing as how basic strategy is calculated isnt it? cuz bs is calculated knowing all 52, cards, well if 2 cards came out, it would be calculated with 50 cards, so its the same thing (this is hard to explain).. if 7 tens came out of the deck, what would be the difference between calculating bs with a 45 card deck, and calculating indices for that?

Mimosine said:

this is the very reason why rounded indices work SO well with very little loss compared to precise indices. additionally since the I-18 only adds a small advantage to your game, slight modification and variation in these numbers matters little.

playing insurance right is worth as much as the I18 combined!

Click to expand...

ya, the I18 according to this one site (very common, every ap here has been there) reduces the house edge by .1% if your not spreading, s17/das, 6 decks.. so we are talking about a very small fraction of .1%, so even if a mistake was huge (lets say +2 for insurance instead of +3), it would still probably only be like .01% overall, but then again, since im not spreading, i will do something simple to give me another .01%, because if my edge is like lets say .25, going from .25 to .26 isnt THAT small of an increase, its 4%

SilentBob420BMFJ said:

do you know what most indexes are based off of? i would guess EV maximization..

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Unless they say otherwise, most indices are EV maximizing. Usually the source will say if they are not.

SilentBob420BMFJ said:

also, you say that its based only off the cards that came out, but thats the same thing as how basic strategy is calculated isnt it?

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The indices are not based on the cards that came out, they are based on the cards that were counted. Like you said, BS is based on the cards that have been removed to make up the hand so it can be very accurate. But when you are counting the cards you do not count them all. For example, the HiLo system doesn’t count the 7,8 or 9. That means your indices ignore these card when you are making playing decisions. That is why they are only estimates. They do not include all of the cards that have come out, only the ones that you counted. They do not take advantage of complete information like BS does.

-Sonny-

SilentBob420BMFJ said:

ya, the I18 according to this one site (very common, every ap here has been there) reduces the house edge by .1% if your not spreading,

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I think it is worth a lot more than .1%, closer to 0.7% I thought. With insurance being roughly equal to 1.1%

I'll have to go look in KO, or BJA later.

What do I know!

SilentBob420BMFJ said:

ya, the I18 according to this one site (very common, every ap here has been there) reduces the house edge by .1% if your not spreading, s17/das, 6 decks

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Are you sure you are not off by a decimal maybe?

Like maybe 0.01% as opposed to 0.1%?

Your figure just seems high to me assuming flat-betting.

Mimosine said:

I think it is worth a lot more than .1%, closer to 0.7% I thought. With insurance being roughly equal to 1.1%

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Whoa - where do these numbers come from lol?

Maybe you are talking about the increased advantage of using I18 to a card-counter compared to the advantage a card-counter would realize if he only used bet spreads?

I don't even have a clue, on the face of it, on where your insurance number comes from lol.

Straighten me out on this if u can lol.

Sonny said:

Unless they say otherwise, most indices are EV maximizing. Usually the source will say if they are not.



The indices are not based on the cards that came out, they are based on the cards that were counted. Like you said, BS is based on the cards that have been removed to make up the hand so it can be very accurate. But when you are counting the cards you do not count them all. For example, the HiLo system doesn’t count the 7,8 or 9. That means your indices ignore these card when you are making playing decisions. That is why they are only estimates. They do not include all of the cards that have come out, only the ones that you counted. They do not take advantage of complete information like BS does.

-Sonny-

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ok, but it should be calculated with the average amount of 7/8/9 that should come out, along with the average ratio of 10:A, and average ratio of 2-6s.. its the same principle as the cut card, you dont know what is behind there, but there should be, on average, such and such in front/back of the cut card.. this stuff is hard for me to explain, but an easy way to look at it is, everything in gambling/chance etc, is based on long run averages; even if your not counting certain cards, you can still assume the average has been played,

(confusing part..) and if your thinking that the tc doesnt account for how many decks have been played, thus you cant multipy decks played by average amount of 7/8/9 etc, you could just assume you are half way thru the decks, which i think may be where the different indexes come from, different authors assume different amounts of decks are played (2, 2.5, 3, etc).. this is really hard to explain, so im sure your confused as hell

Mimosine said:

I think it is worth a lot more than .1%, closer to 0.7% I thought. With insurance being roughly equal to 1.1%

I'll have to go look in KO, or BJA later.

What do I know!

Click to expand...

Kasi said:

Are you sure you are not off by a decimal maybe?

Like maybe 0.01% as opposed to 0.1%?

Your figure just seems high to me assuming flat-betting.

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i got this figure from bjstats.com, and it sounds about right that i would cut the house edge by 20% just by using indexes.. also, this may just be a coincidence, but most books say ~20% of your advantage is from indices

SilentBob420BMFJ said:

ok, but it should be calculated with the average amount of 7/8/9 that should come out, along with the average ratio of 10:A, and average ratio of 2-6s…even if your not counting certain cards, you can still assume the average has been played

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Exactly. But that assumption is why all of your indices are just estimates and not accurate numbers. Just like the assumption that there are equal numbers of each card removed. What if the count is high because all the 2s came out? What if all the 6s came out instead? Would the index number be the same for both cases? No way! So you have to take the average of everything. You’re assuming that the average number of high/low cards have been removed, you’re assuming the uncounted cards are also average, you’re estimating the number of cards in the shoe, you’re estimating the TC, etc, etc. In the end it all adds up to a bunch of estimates based on other estimates that have been rounded/floored or whatever. That’s why it doesn’t matter much if you are off by 1,2,3 or even 4 sometimes. In fact, some risk adjusted indices are 3-5 point higher than the regular EV maximizing ones.

SilentBob420BMFJ said:

different authors assume different amounts of decks are played (2, 2.5, 3, etc).

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I believe many authors take the average of each deck level, which makes the index even more vague.

-Sonny-

SilentBob420BMFJ said:

i got this figure from bjstats.com, and it sounds about right that i would cut the house edge by 20% just by using indexes.. also, this may just be a coincidence, but most books say ~20% of your advantage is from indices

Click to expand...

Thanks Bob.

If you could be more specific about where on that site you got that idea, or from what books, that'd be great.

Again, I am assuming flat-betting yet making the proper playing departure at the recommended TC in a 4 or more deck game. Basically the way that I perceive you most often play. Mostly, I just don't want you to over-estimate your advantage or under-estimate your disadvantage if, in fact, that's what you do.

And I have no problem that using indices with bet spreads can certainly improve your expected win rate by 20%. Or more. Even much more. Often when books say "increase advantage", the underlying assumption is card-counting with spreads.

In the meantime, I'd be a little leary of assuming, if all you do is flat-bet I18 departures, or, indeed, all departures, at the recommended TC's, that the 0.5% or so HA game you may have started with is now down to 0.4% HA.

Or, if anyone else has any ideas of the benefit to a flat-betting card-counter of making only playing departures in a multi-deck game, chime in.

From Schlesinger

Hi-Lo Actual Gain 1000ths of a percent.
Player spreading bets from 1unit to two hands of 6units. These are the average gains for flat betting multiplied by the average bet one has out when he makes the departure. Insurance adds 0.117 to your advantage and the value of the deviation decreases from there.
Insurance
117
16 vs 10
53
15 vs 10
37
10, 10 vs 5
17
10, 10 vs 6
17
10 vs 10
16
12 vs 3
13
12 vs 2
11
11 vs Ace
10
9 vs 2
9
10 vs Ace
7
9 vs 7
7
16 vs 9
7
13 vs 2
7
12 vs 4
6
12 vs 5
6
12 vs 6
4
13 vs 3
4

SilentBob420BMFJ said:

i keep finding different indices from different sources, and im not sure which to believe! for example, if you compare play bj like the pros (blackwood) to (Dead link: http://www.dicedealer.com/chapter_11.htm) (last chart/graphic) you will find EIGHT, i repeat 8 differences! thats insane! 44% of the ill 18 are dif? not to mention if you compare other sources, your bound to find ones that are off by perhaps 2 tc points.. and yes, i am aware of the difference between "= to or greater than" and "greater than" (in this thread, lets treat all indices as "equal to or greater than" which is what most books do.. so do is the 16 vs 10 zero or +1? is the TT vs 6 +4 or +5? is 13 vs 2 zero or -1? etc.. i seriously dont get how people claim how it doesnt matter if indices are off, or that they and the true count are insanely rounded.. how can all of blackjack be pure math, yet the true count and indices can be so vague and still hold accuracy? can som1 shed light on this?

Click to expand...

Well I can see that you've read...

Brock Windsor said:

Hi-Lo Actual Gain 1000ths of a percent.
Player spreading bets from 1unit to two hands of 6units. These are the average gains for flat betting multiplied by the average bet one has out when he makes the departure. Insurance adds 0.117 to your advantage and the value of the deviation decreases from there.

Click to expand...

Can you make a conclusion what the gain would be to a flat-better?

Kasi said:

Can you make a conclusion what the gain would be to a flat-better?

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I conclude it is small...
For a 1-12 spread you are getting the numbers I posted so divide the number posted by what you think the average bet would be for that spread. For an example I will guess at insurance which occurs at TC3+.
4.5% of hands are played at TC3, 3.5% at TC 4, TC5 2%, and TC6+ 2.5%. Spreading 1-12 I assume (perhaps wrongly) the bet at TC 3 to be 6units, TC4 8units, and TC5 10units, and TC6+ 12units. Multiplying the unit bet size by the percentage then adding all four numbers will give you the total units wagered. Divide this by the % of times you are making the deviation will give you an average bet of about 7.8units. The gain in 1000ths 117 divided by 7.8 gives you 15 1000ths of a percentage point as your insurance deviation gain from flat betting. So my loose math says making the insurance deviation, the one that accounts for 1/3rd of all possible gain from index play, will add about 0.015 to your expectation while flat betting. Hopefully this illustrates why BC and proper bet spreads are SO much more important then PE and index plays.
BW

Kasi said:

Are you sure you are not off by a decimal maybe?

Like maybe 0.01% as opposed to 0.1%?

Your figure just seems high to me assuming flat-betting.

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Good Instincts Kasi. Make sure you always read Bob's disclaimer at the bottom of his posts.
"im not always 100% sure about the things i say, nor do i always literally mean what i say, so get off my ass"

Brock Windsor said:

Good Instincts Kasi.

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Actually now, after thinking about it more, maybe I'm the one off by a decimal lol.

Maybe it is alot closer to 0.1% than 0.01% lol.

In which case, Bob, I say to you the words my wife treasures most, no, I know what you are thinking, not "I love you" but

"Your're right and I'm wrong" :grin:

Sonny said:

Exactly. But that assumption is why all of your indices are just estimates and not accurate numbers. Just like the assumption that there are equal numbers of each card removed. What if the count is high because all the 2s came out? What if all the 6s came out instead? Would the index number be the same for both cases? No way! So you have to take the average of everything. You’re assuming that the average number of high/low cards have been removed, you’re assuming the uncounted cards are also average, you’re estimating the number of cards in the shoe, you’re estimating the TC, etc, etc. In the end it all adds up to a bunch of estimates based on other estimates that have been rounded/floored or whatever. That’s why it doesn’t matter much if you are off by 1,2,3 or even 4 sometimes. In fact, some risk adjusted indices are 3-5 point higher than the regular EV maximizing ones.



I believe many authors take the average of each deck level, which makes the index even more vague.

-Sonny-

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but averages are still exact numbers.. for instance, what is the average for a coin flip? 50/50, but to say "well its an average, so we could claim its 45/55 and still be accurate" is foolish.. thats why im confused, because sure you could double 9 vs 2 on +.5 or +1.5, but after a billion hands, there would be an exact number (like 1.1).. i will admit i have yet to read anything that says that indicies must be very accurate (quite the opposite is what i have read), but im just curious.. EDIT: im pretty sure you nailed it with when you said "that have been rounded/floored or whatever", because thats probably exactly why they are off.. i think all rounding should be done at the very end, not as you go, which is probably where the dif comes in.. if your adding 1.2 + 1.2 + 1.2, you shouldnt round them all to 1 to = 3, you should add them all up to get 3.6, then round to 4..

i dont see how deviating from basic strategy when called for is more risky, unless your doubling/splitting.. sorry if your sitting there going "ahhh why doesnt he get it" but im more thorough than most, and believe it or not, while others may say they get it, its possible they dont, they just give up and forget about it.. the #1 thing i fear is getting killed at the bj table wondering not about if i did everything correctly, but if about what i was doing was correct.. i have read probably 10-12 books on gambling, and after all the math, and all the talks of fractions of a penny (vp), to hear "rounding of rounding is ok" and "all the authors are right on dif indicies, it doesnt matter" just doesnt fit in my head.. thanks

Kasi said:

Thanks Bob.

If you could be more specific about where on that site you got that idea, or from what books, that'd be great.

Again, I am assuming flat-betting yet making the proper playing departure at the recommended TC in a 4 or more deck game. Basically the way that I perceive you most often play. Mostly, I just don't want you to over-estimate your advantage or under-estimate your disadvantage if, in fact, that's what you do.

And I have no problem that using indices with bet spreads can certainly improve your expected win rate by 20%. Or more. Even much more. Often when books say "increase advantage", the underlying assumption is card-counting with spreads.

In the meantime, I'd be a little leary of assuming, if all you do is flat-bet I18 departures, or, indeed, all departures, at the recommended TC's, that the 0.5% or so HA game you may have started with is now down to 0.4% HA.

Or, if anyone else has any ideas of the benefit to a flat-betting card-counter of making only playing departures in a multi-deck game, chime in.

Click to expand...

when i say "most books/sites" i probably mean like half of all the sites/books i have read..

Kasi said:

Can you make a conclusion what the gain would be to a flat-better?

Click to expand...

i recently found out i dont have an advantage, because i looked at a frequency chart, which surprisingly showed that the counts of 0-1 occur more than the counts of 1-10 combined, and i play when the rc is +1, which means that of the hands i play, more than half of them are at tc 0-1, and thot that more than half were played at 1+, thus i would have an advantage, so it appears i have a slight disadvantage, but alls i have to do to fix that is wong in at 1 tc instead of 1 rc, and then nearly all my hands will be in the positive (i think +1 tc exactly is slightly negative or neutral)..

edit: actually, i realized something, the frequency chart includes the count of zero, which i dont play, and also, when i get further in the shoe, a count of +1 rc gets closer and closer to +1 tc, so perhaps i am playing at about a dead even game, but i can assure you, i am playing at absolute worst, -.1%.. you make an excellent point, that the 20% gained by indicies is when you are spreading, which woudl probably matter..

the game i play, with bs, is .43%, so by only playing positive counts, obviously that cuts that in half, then remove the count of zero, and add in the fact that the further in the shoe, the closer +1 rc is to +1 tc, and then add in indicies, and i should be at about -.1% at worst, i would think.. then add in comps, which for some reason resorts is sending me every week which is unusual (im used to bi weekly), and remember, i play about 5 hours per week, and im getting on average $10 cash back per week, so thats already $2/hr profit, then add in food, etc..

with comps im playing at an advantage, but i want to play at an advantage without comps included, so i guess i will wait til at least rc +2, or tc +1 or something, and your thinking wonging in at +2 rc isnt that much better than +1 rc, but think about this, a full tc is .5%, so a rc early in the shoe would be about .1%, so that would be a big dif..