Patent Publication Number: US-6663487-B1

Title: Gaming machine with randomly variable pay table

Description:
FIELD OF THE INVENTION 
     The present invention relates to electronic wagering games commonly referred to as slot machines. More particularly, it relates to slot machines including video Poker machines, and the selection of an applicable pay table for winning combination awards. 
     BACKGROUND 
     Slot machines are well known gaming devices. These devices are embodied as electromechanical devices employing rotating reels to present outcomes or purely electronic machines using a video display (commonly referred to as “video games”). For slot machines, a player makes a wager by inputting coins or tokens or wagering accumulated credits and prompts play of the game. A processor controller, upon prompting of play, employs a random number generator (RNG) to select and outcome and controls the reels or video display to display the outcome represented by a combination of selected indicia. RNGs are well known and some gaming jurisdictions may have available, approved, RNGs for use. 
     In most cases, the game has a pre-determined, fixed schedule of winning outcomes and the pay out for each often referred to as the pay table. This pay table is posted so that the player can confirm winning combinations and that appropriate pay out has been made. Upon selection of the outcome, the outcome is compared to the pay table. If the selected outcome combination corresponds to a pre-determined winning outcome combination of the assigned pay table, the player is entitled to an award as dictated by the pay table. The pay outs and/or schedule of winning combinations are selected to provide pay outs to the players while garnering a profit for the machine, referred to as the hold. Based upon the statistical probabilities of each outcome occurring and the pay out for each outcome, the overall hold of the machine can be calculated. Most gaming jurisdictions require that the hold be within defined limits, such as 3%-10%. 
     Another type of gaming machine, generically referred to as a slot machine as well, is a video Poker machine. As is well known, these devices accept player wagers and, based upon the play by the player, produce an outcome represented by a final Poker hand combination. Like other slot machines, the final hand (or outcome) is compared to a pre-selected and fixed pay table of winning outcomes and pay outs. Video Poker pay tables are selected to provide a statistical hold within regulatory limits or as decided by the operator of the game. 
     Various video Poker pay tables have been adopted. When a pay table is adopted, it remains fixed for the game. On example of a pay table which has been adopted is referred to as a six-nine (because of the pay out for flushes and full houses) game and is shown in Table 1 below: 
     
       
         
           
               
             
               
                 TABLE 1 
               
             
            
               
                   
               
               
                 (5 coins bet) 
               
            
           
           
               
               
               
            
               
                   
                 Outcome 
                 Pay out 
               
               
                   
                   
               
            
           
           
               
               
               
            
               
                   
                 Pair of jacks or Better 
                 5 
               
               
                   
                 Two Pair 
                 10 
               
               
                   
                 Three of a Kind 
                 15 
               
               
                   
                 Straight 
                 25 
               
               
                   
                 Flush 
                 30 
               
               
                   
                 Full House 
                 45 
               
               
                   
                 Four of a  Kind 
                 125 
               
               
                   
                 Straight Flush 
                 250 
               
               
                   
                 Royal Flush 
                 4000 
               
               
                   
                   
               
            
           
         
       
     
     Other pay tables provide for greater pay outs for certain fours-of-a-Kind, flushes and the like, with all pay tables being fixed for the game and providing the desired hold. Thus, in some pay tables where a greater than 25:1 payout is provided for certain fours-of-a-kind, pay outs for other combinations is reduced, typically by paying only 1:1 for the more frequently obtained combination of two pair. 
     As stated above, the selected pay table for a machine remains fixed. Thus players often look for a desired pay table when selecting a machine to play. Recently, the trend has been for players to look for games wherein higher pay outs for fours-of-a-kind are provided. 
     In Stupak, U.S. Pat. No. 5,851,147 a gaming device and method is set forth where a player can select from a plurality of displayed candidate pay tables for selection for a video Poker game. Prior to play of the game, the player selects the desired pay table and pays hands according to the selected pay table until the player selects a different pay table. 
     There is a need for a device and method which provides a plurality of differently configured pay tables and which randomly (or pseudo-randomly) selects the pay table for each hand. Such a feature would increase the excitement and fun in playing the machine since the player may have to adopt different strategies for each hand of play according to the pay table and the player may receive, based upon the selection of the pay table, a greater reward than they would receive with other pay tables. 
     It would be advantageous if a device and method were provided where different pay tables are provided and are randomly (or pseudo-randomly) selected for each hand of play. Such an approach would add to the excitement of the game in that the player would not know, prior to selection of the pay, table, what the pay out will be for a winning combination. Where the pay table is selected before play in a video Poker game, the player may have to take into account the characteristics of the selected pay table in deciding the strategy of play. 
     It would be advantageous if a device and method were provided where some pay outs of a pre-selected pay table are randomly (or pseudo-randomly) selected for each hand of play to increase the excitement of the game. 
     It would be desirable also to provide such a method and device where a player has the option of selecting between two or more, undisclosed, randomly (or pseudo-randomly) selected pay tables for each hand of play. 
     It would further be desirable to provide a game which can determine player error in comparison to a pre-selected “ideal play” and to, based upon the calculated error select a pay table for the player to move the game&#39;s hold toward a desired level. 
     SUMMARY OF THE INVENTION 
     There is, therefore, set forth according to the present invention an electronic device and method directed to a wagering game of the type where a player makes a wager and game play indicia are selected by a data processor to result in either a winning or a losing outcome combination of indicia. If the player obtains a winning outcome, the player is issued an award according to the winning outcome combination obtained and the prevailing pay table which defines the award to be paid. 
     The device of the present invention includes a computer processor to control the play of the game and a display controlled by the processor to display the game play indicia. A data structure stores data corresponding to a plurality of pay tables, each pay table presenting a schedule of each game-winning outcome and a corresponding reward. The device includes, for each game played, means for selecting from the first data structure a pay table for the game and for displaying said selected pay table. Upon prompting of play of the game, the processor selects and displays an outcome for the game and compares the outcome to the selected pay table schedule of outcomes. If a game winning outcome has been selected, the device issues the reward corresponding to said selected pay table schedule. 
     In one embodiment, the processor randomly selects the pay table from the data sets representing the pay tables stores at the data structure. In another embodiment, the selection of each data set is weighted such that, statistically, at least one data set is more likely to be selected than another. For example, the data sets may be weighted according to a standard, bell curve, statistical, normal (Gaussian) distribution curve. The data set to be more frequently selected is weighted as the median with data sets selected to be less frequently selected are weighted less than the median data set. 
     In a further embodiment, the player may have the option to select between two or more, undisclosed, pay table data sets which are revealed upon selection. 
     In still another embodiment, the pay table is selected based upon a triggering outcome. For example, while playing under a default pay table, the player obtains a Full House, another pay table would be selected and displayed for a predetermined number of successive plays, e.g. ten. If the player does not obtain a like triggering outcome during those ten hands, the player is returned to the default pay table. If the player obtains the same triggering outcome, e.g. a Full House, the selected pay table prevails for another ten hands. If the player obtains a different, pre-selected, triggering outcome such as a four-of-a-kind, another pay table is selected to prevail for a predetermined number of plays, e.g. ten. Thus the player receives a pay table based upon obtaining triggering outcomes. For example, the triggering outcome may put the player into a more aggressive pay table so that the player can play to a pay table providing higher pays for higher ranked outcomes. 
     In still another embodiment, the player may be put into a different pay table based upon coin in. From a default pay table, the gaming machine counts coin in and, based upon coin in would trigger the application of another, different pay table for a predetermined number of following plays. 
     The method according to the present invention includes providing a memory storing a plurality of pay table data sets, each pay table data set including a schedule of designated winning outcomes and a corresponding reward, selecting for each hand a pay table data set and for any winning outcome issuing a reward corresponding to said selected pay table. 
     According to the various aspects of present invention, a device and method which provides for a variable selection or selection of the applicable pay table, which provides for random selection of the applicable pay table, for pseudo-random selection of the pay table and which provides for the player to select between undisclosed, selected pay tables. Still further, according to one embodiment, the processor determines player error in comparison to a pre-selected play strategy, and selects a pay table for a plurality of hands which increases the player&#39;s chances to win. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other features and advantages will become appreciated as the same becomes better understood with reference to the description, claims and drawings where; 
     FIG. 1 illustrates a device according to the present invention; 
     FIG. 2 is a logic diagram concerning the play of a game according to the present invention; 
     FIG.3 shows a display for play according to another aspect of the present invention; and 
     FIG. 4 shows one method for weighting the selection of pat tables. 
    
    
     DESCRIPTION 
     Turning to the drawings, there is shown at FIG. 1 a device  10  according to the present invention. The device has a housing  12  containing a controller-processor (not shown) and has a video display  14 . The display  14  is controlled by the processor to, present the various displays for the play of the game according to the method of the present invention. Accordingly, where the game played on the device  10  is video Poker, the display  14  displays a pay table  16  which sets forth a schedule of winning game card combinations as well as the pay off for obtaining each. A portion of the display  14  is also allocated for the display of indicia for the play of the game and the display of a final outcome. Where the device  10  is a video Poker game as illustrated, the indicia are representations of playing cards and are, as is known in the prior art, displayed at the display  14  in a row of five cards  18   a-e.    
     Not shown are means for a player to input a wager. These means may be a coin acceptor, cash validator or debit/credit card reader as are known in the art. The wager input means communicates with the processor to register the amount of the wager and, if a maximum wager is made, prompt play of the game. 
     To control the play of the game the usual and accepted control buttons are provided. These buttons include a cash out button  20  which the player depresses to control the processor to dispense coins/tokens to cash the player out of the device  10 . A bet  1  unit button  22  permits the player to wager one token or unit at a time and a max bet button  24  permits the player to wager the maximum permitted by the device  10 . When a maximum bet is made, play of the game is automatically prompted. When less than the maximum is wagered, a deal button  26  is depressed to prompt play. 
     The various control buttons for the player to control the play of the device  10  may be incorporated into a touch screen display  14 ′ if desired. 
     To play the device  10 , where the game is video Poker, the player inputs a wager, a single unit up to the maximum, and prompts play of the game. When play is prompted, the processor randomly selects from a universe of data representing each card of a deck of cards, an initial hand of five cards  18   a-e  and displays at the display  14  the values, i.e. faces, of the cards  18   a-e  of the initial hand. The player, using selection buttons (not shown) or the touch screen display  14 ′, selects which of the cards  18   a-e  of the initial hand to discard. Any cards  18   a-e  selected for discarding are replaced by cards selected by the processor to produce a final hand outcome. 
     The card combination of the final hand outcome is compared to a schedule of winning outcomes and rewards referred to herein as the pay table. If the player has obtained a winning outcome, the processor issues the reward to the player based upon the player&#39;s wager and the pay table schedule. 
     The pay table for the game, according to the prior art, remains static and fixed for the play of all hands. For the player to have a different prevailing pay table, they must change games by moving to a different machine or changing games on the existing machines where the processor stores multiple games. 
     Examples of some accepted pay tables for video Poker machines are shown in the following tables: 
     
       
         
           
               
             
               
                 TABLE 1 
               
             
            
               
                   
               
               
                 (5 coins bet) 
               
            
           
           
               
               
               
            
               
                   
                 Outcome 
                 Pay out 
               
               
                   
                   
               
            
           
           
               
               
               
            
               
                   
                        Royal Flush 
                                   4000 
               
               
                   
                 Straight Flush 
                 250 
               
               
                   
                 Four of a Kind 
                 125 
               
               
                   
                 Full House 
                 45 
               
               
                   
                 Flush 
                 30 
               
               
                   
                 Straight 
                 25 
               
               
                   
                 Three of a Kind 
                 15 
               
               
                   
                 Two Pair 
                 10 
               
               
                   
                 Pair of Jacks or Better 
                 5 
               
               
                   
                   
               
            
           
         
       
     
     
       
         
           
               
             
               
                 TABLE 2 
               
               
                   
               
               
                 (5 coins bet) 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
            
               
                   
                               Royal Flush 
                            4000 
               
               
                   
                 Straight Flush 
                 250 
               
               
                   
                 Four of a Kind 
                 400 
               
               
                   
                 Full House 
                 40 
               
               
                   
                 Flush 
                 35 
               
               
                   
                 Straight 
                 25 
               
               
                   
                 Three of a Kind 
                 15 
               
               
                   
                 Two Pair 
                 5 
               
               
                   
                 Pair of Jacks or Better 
                 5 
               
               
                   
                   
               
            
           
         
       
     
     
       
         
           
               
             
               
                 TABLE 3 
               
               
                   
               
               
                 (5 coins bet) 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
            
               
                   
                      Royal Flush 
                 4000 
               
               
                   
                 Straight Flush 
                 250 
               
               
                   
                 Four Aces/w2,3,4 
                 1000 
               
               
                   
                 FourAces 
                 800 
               
               
                   
                 Four 2s,3s,4s/w2,3,4 
                 800 
               
               
                   
                 Four 2s,3s,4s 
                 400 
               
               
                   
                 Four 5-King 
                 250 
               
               
                   
                 Full House 
                 35 
               
               
                   
                 Flush 
                 30 
               
               
                   
                 Straight 
                 25 
               
               
                   
                 Three of a Kind 
                 15 
               
               
                   
                 Two Pair 
                 5 
               
               
                   
                 Pair of Jacks or Better 
                 5 
               
               
                   
                   
               
            
           
         
       
     
     
       
         
           
               
             
               
                 TABLE 4 
               
               
                   
               
               
                 (5 coins bet) 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
            
               
                   
                       Royal Flush 
                       4000 
               
               
                   
                 Straight Flush 
                 250 
               
               
                   
                 FourAces 
                 400 
               
               
                   
                 Four 2s,3s,4s 
                 200 
               
               
                   
                 Four 5-King 
                 125 
               
               
                   
                 Full House 
                 35 
               
               
                   
                 Flush 
                 30 
               
               
                   
                 Straight 
                 25 
               
               
                   
                 Three of a Kind 
                 15 
               
               
                   
                 Two Pair 
                 5 
               
               
                   
                 Pair of Jacks or Better 
                 5 
               
               
                   
                   
               
            
           
         
       
     
     It should be understood that other pay tables exist and can be created and can be incorporated into the device  10  and method of the present invention. Further, the present invention could incorporate Deuces Wild pay tables, Joker&#39;s Wild pay tables and others as well. 
     According to the device  10  and method of the present invention, the field of desirable pay tables are stored in a data structure (e.g. data storage device such as a ROM, CD-Rom) as data sets assigned at a discrete addresses. Prior to the play of each hand, a pay table is selected from the stored field and is displayed as the pay table  16  at the display  14 . The selected pay table  16  sets forth the schedule of winning outcome combinations and the corresponding pay outs for each. The processor then selects and displays the cards  18   a-e  and the player plays the video Poker hand by selecting discards, if any, to produce a final outcome, i.e. a final, five card, Poker hand. The processor compares the final outcome to the schedule of winning outcome hands of the selected, prevailing pay table. If the player has obtained a winning outcome, he receives a pay out as dictated by the selected pay table. 
     After the hand has been completed, a new wager is made and the prevailing pay table is selected. 
     Various means can be used to select the prevailing pay table for the hand. One means is for the processor, using a random number generator (RNG) to randomly select from the stored pay table data sets, the prevailing pay table for that hand. Thus each pay table would have the same statistical probability of being selected. 
     Another means by which the prevailing pay table may be selected is to provide a pseudo random selection by weighting certain pay tables. With reference to FIG. 4, one such pseudo-random selection means includes using a Gaussian distribution curve (bell curve) approach and selecting the pay table which statistically should be selected more frequently, to the center or of the curve. Thus, for example, the pay table of Table 1, may occupy the center position and thus be statistically more likely than other pay tables to be selected. This weighting in regards to the selection of the pay tables may be accomplished by data mapping, i.e. mapping a number selected by the RNG to a Gaussian-like map for the data addresses, by duplicating pay tables at different addresses, the number of duplications matching a desired distribution scheme, or by any other suitable means. It should also be understood in regards to weighting, that any desirable weighting for the selection of pay tables could be used such as a linear distribution, weighting only one or several pay tables differently, or the like. 
     Thus, with reference to FIG. 4, it is more like that a pay table according to Table 1 would be selected, however, other pay tables will be selected such that, over a population of random selections, statistically each pay table would be selected according to the curve. 
     While the processor may simple select and display the prevailing pay table, in a further embodiment of the present invention as shown in FIG. 3, the processor may select a plurality of undisclosed pay tables from which the player makes a selection. For example, upon prompting of play the backs of three playing cards  50   a-c  may be displayed. Each playing card back represents a selected but undisclosed pay table. The player touches one of the card  50   a-c  backs and thereby selects the prevailing pay table. This feature adds to the excitement of the game in that the player feels they have a degree of control over the selection of the pay table. 
     As stated above, in the preferred embodiment, the prevailing pay table is selected before the play of each hand. However, according to another embodiment, the pay table or at least the rewards, may be selected after the play of the hand. 
     Furthermore, the method and device according to the present invention, rather than providing as data sets complete pay tables, the data sets may only have differing pay outs for certain outcomes, e.g. certain fours of a kind. Thus, each prevailing pay table may have a static component such as the rewards for three of a kind, straights, flushes, straight flushes, and a volatile component such as the pays for Royal Flushes, certain fours of a kind or the like. 
     With reference to FIG. 2, a logic diagram for the device  10  and method of the present invention is shown. At  60  the device  10  is in an idle mode and at  62  the player inputs a wager and prompts play of the device  10 . The processor at  64  selects the pay table according to any one of the above techniques including at  64   a , a random selection, at  64   b  a weighted selection, at  64   c  selection including player selection such as described with reference to FIG. 3, or at  64   d  selecting a pay for certain, selected combinations. 
     According to yet a further embodiment, the processor may monitor over a series of hands the player&#39;s play in comparison to one or more pre-determined strategies for play. An example would be where the player always holds two pair. The processor would, based upon this recognized strategy, would be programmed to select for the player, for example, a Table 1 pay table which provides for a 2:1 pay for two pair. The processor would monitor play and when determined may select another pay table. As another example, if the player is obtaining fours of a kind frequently, the processor may select a pay table which has a higher pay for fours of a kind. 
     Thus, with reference to FIG. 2 at  64   e  player error is calculated and the most beneficial pay table is selected. The processor at  66  displays the selected pay table  16  at the device  10  and at  68  the processor deals the initial cards for the play of the hand. At  70  the player decides whether to discard cards and if so at  72  replacement cards are dealt to result in the final outcome of a five-card Poker hand. At  74  the processor compares the final outcome to the schedule of winning hands set forth in the selected pay table and, if a winning outcome has been obtained, at  76  issues the corresponding award as dictated by the pay table. 
     To play the next hand, another wager is made and the pay table is selected. 
     According to another embodiment, the processor  66  operates under a default pay table, e.g. Table 1 until the player obtains a preselected, triggering outcome or one of a plurality of triggering outcomes. As but an example if, while playing under the default pay table, the player obtains a Full House, the processor  66  would select a Table 2 pay table to apply to, for example, the next following ten plays. If the player does not obtain a Full House or better during the next ten plays, the processor  66  returns the player to the default pay table. If the player obtains another Full House during those next ten plays, the Table 2 pay table would apply for the next ten hands. If during the ten hand play sequence, the player obtains a different pay table triggering outcome, e.g. a four-of-a-kind, the processor  66  would apply, for example a Table 3 pay table for the next ten plays. If the player does not obtain another four-of-a-kind during those next ten plays, the processor returns the [player to the default pay table or to another pay table, e.g. to the Table 2 pay table for another ten plays. This sequence of using triggering outcomes continues during play selecting prevailing pay tables and/or returning the player to the default pay table. 
     In still another embodiment, the processor  66  monitors the coin in (wagers made). After a preselected amount has been wagered under a pay table, e.g. Table 1, the processor  66  would apply a different pay table, e.g. Table 2, for a preselected number of plays or coin in. The processor  66  may then return the player to the default pay table or may select another pay table, randomly or pseud-randomly to apply for the next following coin in or number of plays. 
     While the description above has been directed to video Poker games, it should be understood that the method and device could also be employed for other slot machine games, such as the video slot machines depicting reels with indicia spinning to select and outcome and games such as multi-hand video Poker games such as are embodied in U.S. Pat. No. 5,823,873 titled “Method of Playing Electronic Video Poker Games” issued Oct. 20, 1998 to Moody wherein, for each hand, a different and prevailing pay table may be selected. 
     While I have shown and described certain embodiments of the present invention, it is to be understood that it is subject to many modifications and changes without departing from the spirit and scope of the appended claims.