Balancing the book: Is it necessary and sufficient?

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Dudley Stark
Dominic Cortis


The solvency of bookmakers has only recently been placed in the spotlight even if it is a multibillion dollar sector. It is industry knowledge that bookmakers attempt to 'balance the book' by adjusting odds in relation to wagers made. This paper proves that the only way that profits are known with certainty is if and only if wagers are in proportion to probabilities implied by odds.

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