Helly metric

In game theory, the Helly metric is used to assess the distance between two strategies. It is named for Eduard Helly.

Consider a game ${\displaystyle \Gamma =\left\langle {\mathfrak {X}},{\mathfrak {Y}},H\right\rangle }$, between player I and II. Here, ${\displaystyle {\mathfrak {X}}}$ and ${\displaystyle {\mathfrak {Y}}}$ are the sets of pure strategies for players I and II respectively; and ${\displaystyle H=H(\cdot ,\cdot )}$ is the payoff function.

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