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Does Bob have a uniquely best gladiator ordering

Question

Alice owns four gladiators of strengths 1,2,3,41,2,3,4; Bob owns four of strengths 4,5,9,124,5,9,12. Fights are one-on-one: in each round Alice first nominates one of her surviving gladiators, then Bob nominates one of his survivors to face it. A bout between strengths xx and yy is won by the strength-xx fighter with probability xx+y\dfrac{x}{x+y} (no draws), the loser dies, and the winner keeps the same strength for future bouts. Whoever still has a gladiator when the other side runs out wins. Is there a strategy for Bob that gives him a strictly higher chance of winning than every other strategy? Answer 11 for yes, 00 for no.

Short answer

00 (no). Model each gladiator of strength xx as a bulb with an exponential lifetime of mean xx that only burns while fighting; memorylessness reproduces the xx+y\tfrac{x}{x+y} rule and constant strength. Bob wins exactly when his total burn time outlasts Alice's, which does not depend on the order of matchups, so every strategy gives the same probability.

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