Pitch Playing Agent Project for Into to AI Jody Ammeter

The Game of Pitch This project is based on Oklahoma, 13-pt, 4-player Pitch. This project is based on Oklahoma, 13-pt, 4-player Pitch. Players sitting across from each other are partners. Players sitting across from each other are partners. Each player is first dealt 9 cards. Each player is first dealt 9 cards. Then a round of bidding follows. Legal bids 5 – 13. Then a round of bidding follows. Legal bids 5 – 13. Highest bidder chooses suit to be played. Highest bidder chooses suit to be played. Everyone discards all cards of other suits. Everyone discards all cards of other suits. Each player is then dealt enough cards to give them 6 cards in their hand. Each player is then dealt enough cards to give them 6 cards in their hand. The hand is then played. The highest bidder leads on the first trick. Whoever takes the trick leads on the following trick. The hand is then played. The highest bidder leads on the first trick. Whoever takes the trick leads on the following trick. Only cards of the chosen suit are played Only cards of the chosen suit are played Points are totaled at the end of each hand. Points are totaled at the end of each hand. The game ends when a team scores 52 points. The game ends when a team scores 52 points.

Card Rank and Scoring Cards rank from high to low as follows: Cards rank from high to low as follows: Ace, King, Queen, Jack, Off-Jack, High Joker, Low Joker, 10, 9, 8, 7, 6, 5, 4, 3, Off-3, 2 Ace, King, Queen, Jack, Off-Jack, High Joker, Low Joker, 10, 9, 8, 7, 6, 5, 4, 3, Off-3, 2 Points are awarded as follows: Points are awarded as follows: 1 pt each is awarded to the team who takes the tricks containing the following: 1 pt each is awarded to the team who takes the tricks containing the following: Ace, Jack, Off-Jack, High Joker, Low Joker, 10 Ace, Jack, Off-Jack, High Joker, Low Joker, 10 3 pts each is awarded to the team who takes the tricks containing the following: 3 pts each is awarded to the team who takes the tricks containing the following: 3, Off-3 3, Off-3 1 pt is awarded to the team who plays the 2 1 pt is awarded to the team who plays the 2

Agents Bidding Method The agent forms a bid using a simple evaluation function. A bid is calculated for each suit. The agent forms a bid using a simple evaluation function. A bid is calculated for each suit. Face cards, Jokers, and the deuce all have assigned point values. Face cards, Jokers, and the deuce all have assigned point values. Points are also added for having multiple cards of the same suit. Points are also added for having multiple cards of the same suit. The total of these points is the agents bid for that suit. The total of these points is the agents bid for that suit. The highest of these bids is then made in the corresponding suit. The highest of these bids is then made in the corresponding suit.

Agents Method of Play The agent is given perfect information. The agent is given perfect information. Sees other players hands, and knows what cards have already been played on a given trick. Sees other players hands, and knows what cards have already been played on a given trick. The agent then builds a search tree for the trick and uses minimax to maximize points received on that particular trick. The agent then builds a search tree for the trick and uses minimax to maximize points received on that particular trick. Drawback: Does not plan ahead, and therefore does not always play optimally. Drawback: Does not plan ahead, and therefore does not always play optimally.

Building the Search Tree The agents hand becomes the first level of the search tree. The agents hand becomes the first level of the search tree. The next players hand, Opponent 1, becomes the children of the nodes representing the agents hand. The next players hand, Opponent 1, becomes the children of the nodes representing the agents hand. The next players hand, Agents Partner, becomes the children of each of the nodes representing Opponent 1’s hand. The next players hand, Agents Partner, becomes the children of each of the nodes representing Opponent 1’s hand. The next players hand, Opponent 2, becomes the children of each of the nodes representing the agent’s partner’s hand. The next players hand, Opponent 2, becomes the children of each of the nodes representing the agent’s partner’s hand. If a player has already played on the trick, his hand just consists of the card that was played on this trick. If a player has already played on the trick, his hand just consists of the card that was played on this trick.

Example Search Tree Agent’s Leading, Possible plays: Ace, High Joker Agent’s Leading, Possible plays: Ace, High Joker Opponent 1: Jack, deuce Opponent 1: Jack, deuce Partner: 8, 3 Partner: 8, 3 Opponent 2: Low Joker Opponent 2: Low Joker A J H J LLLLL 38 LLL Max Min Max

Questions?