OCR Further Discrete 2020 November — Question 2

Exam BoardOCR
ModuleFurther Discrete (Further Discrete)
Year2020
SessionNovember
TopicGroups

2 Annie and Brett play a two-person, simultaneous play game. The table shows the pay-offs for Annie and Brett in the form ( \(a , b\) ). So, for example, if Annie plays strategy K and Brett plays strategy S, Annie wins 2 points and Brett wins 6 points.
Brett
RST
\cline { 3 - 5 } \multirow{3}{*}{Annie}K\(( 7,3 )\)\(( 2,6 )\)\(( 5,3 )\)
\cline { 3 - 5 }L\(( 1,5 )\)\(( 8,2 )\)\(( 2,5 )\)
\cline { 3 - 5 }M\(( 3,2 )\)\(( 1,5 )\)\(( 4,6 )\)
\cline { 3 - 5 }
\cline { 3 - 5 }
    1. Determine the play-safe strategy for Annie.
    2. Show that the play-safe strategy for Brett is T.
    1. If Annie knows that Brett is planning on playing strategy T, which strategy should Annie play to maximise her points?
    2. If Brett knows that Annie is planning on playing the strategy identified in part (b)(i), which strategy should Brett play to maximise his points?
  1. Show that, for Brett, strategy R is weakly dominated.
  2. Using a graphical method, determine the optimal mixed strategy for Brett.
  3. Show that the game has no Nash equilibrium points.