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I

I. Acronym and reference to an American Indian casino.

IC. Acronym for insurance correlation.

IBJ. Acronym for the software program International Blackjack Professional.

ID. Acronym for identification.

identification.  (ID) The legal papers in your wallet or purse that identify who you are.  Examples of identification include driver license, credit cards, birth certificate, social security card, etc.  See false identification.

Illinois. See riverboat gambling.

Illinois Rules. TBD

Illustrious 18. Term coined by Donald Schlesinger to refer to the play variations that provide players the most gain from varying from basic strategy. These plays are:

According to Schlesinger, the insurance play alone is worth over 30% of all the gain. The BIG 3, insurance, 16 vs 10 and 15 vs 10, account for nearly 60%. The top 12 plays account for more than 90%. The above study is applicable for a typical 4-deck shoe game using the Hi-Lo system. A different counting system may add or remove a few plays to or from this list.  See Fab Four.  See bet variation.
[9/86 Schlesinger Attacking the Shoe BJF 5]
[88 Griffin Theory of Blackjack 30]
[Sum 92 Dalton The Most Important Plays for Card Counters BJR]
[97 Schlesinger Blackjack Attack 70]
[ http://www.bjmath.com/bjmath/tcindex/r18.htm ]

Imming, John.  Author of several blackjack simulation software programs collectively called Real World Casino.  Imming masterpiece of blackjack analysis software is his Universal Blackjack Engine.

implied count.  An implied count is an educated guess that takes into account what you believe another player is holding for the purpose of playing your hand more accurately.  For example, if the dealer has a small card up, and two players on your right don't bust after being hit with large cards you can estimate that each of these players have two small or neutral cards in the hole.  An implied count is usually only used in the face-down single deck game. 

in shuffle.  A modified perfect shuffle.   See out shuffle.
[03 Poolside The Poolside Report: Blackjack Ace Tracking]

independent trials. As in independent trials processes. A mathematical concept that applies to games such as craps and roulette where each play of the game is uninfluenced by past outcomes and, in turn, has no influence on future outcomes. Blackjack is not an independent trials process but rather a dependent trials process. The cards that already have been played do affect the odds on subsequent hands.
[66 Thorp Beat the Dealer 42]
[77 Epstein The Theory of Gambling and Statistical Logic Chap 2]
[84 Thorp The Mathematics of Gambling 1]

index. 1) The number in the upper left and lower right corners of a playing card, which gives its value. 2) The count necessary to vary from basic strategy and generally expressed as a negative or positive number. (e.g., the Hi-Lo index for a player 16 versus a dealer 10 is 0. Whenever the count is ³ 0 the player would vary from basic strategy and stand.)

Indian blackjack. At time of writing, there were numerous Indian reservations throughout the United States that offer casino blackjack. Many of these games offer Las Vegas Strip rules with maximum bets of over $1000. Examples include reservations in the following states:

Indiana. At time of writing (1993), the Indiana General Assembly had ratified a state budget allowing up to 11 riverboat casinos including:

Indiana Rules. TBD

indice. See index.

Instant Blackjack Answers Wheel. {BS}. Practical Products, Margate, NJ. A plastic 4 inch diameter calculator-type wheel that provides basic strategy, including when to surrender.
[80 Casino & Sports Vol.10,26]

insurance. An optional side bet offered to players by most casinos. The player is betting that the dealer has a 10-valued card down when he shows an ace as an up-card. Players may wager up to half of their original bet to insure their hands against a dealer having a natural. Bets must be placed in the designated area on the layout in front of the players. No money changes hands when the player wins this bet since it pays 2 to 1 unless the player also has a natural. 

Frequently Asked Question
When would I ever want to take insurance (or even money)?

Basic strategy for the insurance bet is to never take it. The Hi-Lo count strategy is to take insurance only if the count per deck is greater than 1.5 for single-deck, 2.4 for double-deck and 3 in multi-deck games. As can be seen by the percentages below, insurance is much less important to the card counter in multi-deck games than it is in single-deck. In a randomly shuffled 52-card deck the probability of the dealer having a 10 as his hole-card is 16/51 (31.37%). The insurance bet is profitable only if this probability is greater than 33.33%. See call for insurance. See even money.  See insurance line.  See Rules of the Game.

HA (1 Deck) = 5.88%
HA (8 Decks) = 7.47%

insurance correlation. (IC) TBD

insurance counter. {CS}. A player who is using a special count designed to signal the insurance decision more accurately than a normal card count would. This counter is usually not playing but only giving signals to a seated player.  See insurance.

insurance line. The area of a blackjack table layout on which the insurance bet is placed.   See insurance.

integrity. Described in some sources as a measure of the quality of a game in progress. Good integrity is often associated with things happening the way the probabilities of the game say they should be happening. Bad integrity is just the opposite. The BIAS Barometer methods claim the ability to quantify this factor. See TARGET.
[85 Patterson TARGET Manual 6]

Internet. A reference to the World Wide Web and the thousands of associated Web sites.  There are many Web sites related to the game of blackjack as referenced in the links below. 
[ http://dmoz.org/Games/Gambling/Blackjack]
[ http://www.BJRnet.com ]

IOU. See marker.

Iowa. See riverboat gambling.

Iowa Rules. TBD

IRC. 1) Acronym for initial running count. 2) Acronym for Internet Relay Chat, a commercially free chat program.

Ita Count. See Green Fountain count.

Last Update 04/15/04