Creating a Blackjack Card Counting Strategy

September 29th, 2010 by admin Leave a reply »

Card counting strategies range from fairly simple to absurdly complex. This article provides instructions on creating a card counting strategy and in doing so describes the various characteristics of counting systems. It may be of interest even if you don’t wish to create a strategy but want to learn about the make-up of such systems.

Creating a new strategy is not difficult if you start with an existing strategy. If you wish to start from scratch there is a bit more work. There are plenty of strategies in the books. But, many people do like to at least modify a current strategy to better fit their needs.

Card Counting Tools

The following tools are needed:

  • Efficiency Calculator – Tells you how efficient a particular count is
  • Index Generator – To create new playing indexes
  • Simulator – To fine-tune and measure the effectiveness of the new strategy

Card Counting Tag Values

First you need to settle on the card point values. If you have already done this, you can skip to the Index Generation section. Although reading this section may add to your understanding. Each card has a point value like +1 or -1. There are several characteristics of counts as follows:

  • True Count vs. Running Count – As cards are seen, you keep a running sum of the card tag values. Running Count systems use this count for both betting and playing decisions. True Count systems require that you divide the RC by a number representing the number of cards that have been seen. There are various methods of converting RC to TC (e.g. division, multiplication, tables.) TC systems generally use this TC for all playing decisions. Most also use it for betting decisions. There are exceptions to both of these rules. RC strategies are generally easier to use and TC strategies are generally more accurate.
  • Balanced vs. Unbalanced – In a balanced strategy, all of the point values sum to zero. In an unbalanced strategy, the sum of all the cards is positive. Unbalanced strategies have an advantage because they can be used in the easier running count systems. Although they can also be used in TC systems. Balanced strategies have an advantage in that they are generally a bit more accurate (there are exceptions) and the count hovers around zero making counting easier and betting strategies easier.
  • Ace-Reckoned vs. Ace-Neutral – Generally the Ace is counted as a negative number (Ace-reckoned) or zero (Ace-neutral.) Ace-Reckoned strategies are generally better for shoe games and Ace-Neutral strategies are generally better for single and double deck. (Not always true.) There are compromise strategies (e.g. Zen, UBZ II) where the Ace is counted at half of the normal value. This is particularly good for double-deck and not bad for single deck or shoes. These days, Ace-reckoned strategies are more popular.
  • Level – The level of a strategy refers to the highest value assigned to cards. Level 2 and 3 card counting methods are more efficient, but quite a bit more difficult for most people. Level 3, 4 & 5 strategies also exist. But this is overkill. The most popular strategies these days are level 1. In a level 1 strategy, tens are counted as -1 and some or all low cards are counted as +1.
  • Side Counts – Some strategies use one or more side counts. The most common is counting the Aces in a separate count to make betting more accurate in Ace-neutral systems. This is because Aces are large cards for the purposes of betting but small cards for the purposes of playing when you don’t have a Blackjack.
  • Suit/Color Aware Counts – Some count will have different tag values for red and black cards. Examples are Red7 & KISS. The attempt here is to gain most of the advantage of a higher level strategy without the higher range of counts. I would expect the error rate would increase somewhat but have no figures for this.
  • Other ease of use considerations – The fewer the number of cards counted the easier the count. Also, the more card pairs that add to zero the better. This is because most counters count pairs of cards when possible. If you see a +1 and a -1 card at the same time, you automatically ignore them since they sum to zero.

Now, how do we decide on the card tag values? First you need to decide on the above characteristics. Second, it is good to take a look at the popular strategies that exist. Next, you need to understand Betting Correlation, Playing Efficiency and Insurance Correlation. These are terms created by Peter Griffin in Theory of Blackjack. Reading this book will help you a great deal. These terms are defined as:

  • Playing Efficiency – PE indicates how well a card counting system handles changes in playing strategy. Playing efficiency is particularly important in hand-held games (one or two decks.)
  • Betting Correlation – BC is defined as the correlation between card point values and the effect of removal of cards. It is used to predict how well a card counting system predicts good betting situations and can approach 1.00 (100% correlation.) BC is particularly important in shoe games (six or eight decks.)
  • Insurance Correlation – IC is defined as the correlation between card point values and the value of cards in Insurance situation. A point value of -9 for tens and +4 for all other cards would be perfect for predicting if an Insurance bet should be placed.

Index Generation

Once you have your card values, you need to generate indexes. First, you need to make a few general decisions:

  • Initial Running Count – The IRC is the count you start with after a shuffle. Balanced strategies nearly always have an IRC of zero. This causes the count to hover around zero. A few people start with a higher number because they don’t like to count negative numbers. This has no effect on the efficiency of a strategy. Unbalanced strategies usually have negative IRC’s. This is because the count rises as the shoe is played. The IRC is often set so that there is an advantage after the count becomes positive. Also, different IRC’s are generally used for different numbers of decks. This is not necessary; but makes it easier to remember playing and betting decisions since the count has to rise significantly farther for shoes than for single-deck. Some people use zero for unbalanced IRC’s to avoid large negative numbers.
  • True Count Calculation – You need to decide how to convert the running count to the true count if your strategy uses True Count decisions. The most common methods are to divide by the number of full decks or half decks remaining. There is little difference in overall effectiveness. Full-deck is slightly better for betting and half-deck is slightly better for playing. HiLo Lite and the 1998 version of Zen divide by quarter-decks remaining. This makes betting a bit easier; but a bit less accurate. (You can see this explained in Blackbelt in Blackjack by Arnold Snyder when the next version is printed. It is currently out of print.) Some people use multiplication instead of division. Another method is to use a table of True Counts by shoe depth and running count. This is described in Blackjack Bluebook II by Fred Renzey.
  • Rounding/Truncating/Flooring – Nearly everyone uses integer index values for playing decisions. So, how do you round the true count after division? It doesn’t matter greatly as long as you use the same method for play and index generation. But, Flooring is currently preferred. That is, if there is a fraction, round down to the next lower value.
  • Which indexes – In older strategies huge numbers of indexes were used. But, most indexes have very little value. You can find a discussion on this subject in Blackjack Attack by Don Schlesinger. (You should read this book for many other reasons.) See the discussion on Illustrious 18 and Catch-22. Theory of Blackjack also has a discussion on the value of indexes. But, it is concerned primarily with single-deck and doesn’t take into account the frequency of decisions.
  • Risk-Averse vs. Expectation Maximizing Indexes – Older strategies generally used expectation maximizing indexes. (There are exceptions.) Such indexes result in decisions that give the greatest average gain for each bet. But, this is not always the best bet as the gain is so small in some cases it may not be worth the extra risk as in close doubling down decisions. Risk-Averse indexes reduce the risk which reduces the variance which allows you to slightly increase your betting levels. This provides a slight overall improvement in results. RA Indexes are now preferred since they perform a bit better with no extra effort. Blackjack Attack contains a discussion on RA indexes.
  • Index Compromises – Older strategies used the best possible indexes they could calculate at the time. Some newer strategies make compromises for ease of use. For example, the double down indexes for 9 vs. 2 and 9 vs. 7 may not be the same; but they are so close you can compromise and make them the same. This makes them easier to remember and use. If you wish to use compromise indexes; you will need to first generate the correct indexes using an index generator and then use trial and error with simulations to test various compromises. Red7, HiLo Lite, Basic Omega II and 1998 Zen use compromise indexes.
  • Rules Compromises – Stand on 17 vs. Hit on 17, Multi-deck vs. Single-deck, Double after Split vs. no DAS. These all affect indexes. You need to decide if you want to go through the effort of using different indexes or determining what games you will most often play and just use those indexes. Or, compromise by using indexes that are in-between.
  • Composition Dependent indexes – These are indexes that look at the exact composition of your hand (8, 6, 2 vs. 10) instead of the total of the hand (16 vs. 10.) They add slightly to system effectiveness. But, few people use them.
  • Multi-Parameter Indexes – These are used along with side-counts to improve playing decisions. MP Index Tables are rarely used today.

Once you have created the indexes, you will want to run sims with different rules and penetrations to test your system. The best method of evaluating the overall strength of a strategy is by the SCORE as described in Blackjack Attack.

Hints and Tips

  • Read The Theory of Blackjack by Peter Griffin. Particularly chapters 3 and 4 as they will explain the value of card tags and indexes.
  • Some strategies use compromise indexes. Hi-Lo Lite and Red 7 are examples. These are indexes that are changed so that many decisions use the same index. To create these, generate the accurate indexes first and then run sims with different indexes to see which ones can be changed without impacting overall SCORE. These sims must be over two billion rounds.
  • Indexes do not make a huge difference in shoe games. The more decks, the less value you get out of accurate indexes.
  • The gain from using risk-averse indexes is really quite small. But, there is no downside.
  • To accurately calculate the SCORE, you must use an optimal betting ramp.
  • Some Split indexes are very strange. Splitting or not splitting goes back and forth as the count changes. This is because they are both offensive and defensive. That is, sometimes you split to make more money and sometimes you split to lose less money. 2, 2 v 3 or 3, 3, v 7 for example. It really doesn’t matter much what you do with these hands.
  • Indexes can change as the penetration changes. This is particularly true with unbalanced strategies, but also true with balanced strategies.

Norman Wattenberger Author of the Casino Verite Blackjack suite of card counting software products.

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