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Eric
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Alice and Bob have $N_A$ and $N_B$ warriors under their command, numbered $1$~$N_A$ and $1$~$N_B$ respectively. Alice has $1$ fighting power at her disposal, and Bob has $b$ ($b\gt 0$). Before the game, they privately distribute their power between their warriors. When the game begins, both send their warrior #1 to a 1-to-1 fight. If a warrior with power $x$ fights one with power $y$, the former wins with probability $\frac{x}{x+y}$, and the latter with $\frac{y}{x+y}$. If #1 is defeated, #2 is sent to continue the next round of fight, so on and so forth until one side has all of their warriors defeated and loses the game. There's a small twist though: after a warrior defeats an $x$ power opponent, his power will increase by $cx$ ($c\geq 0$).

Clearly, a player's strategy is their method of distributing fighting power.

Question 1: givenif Alice and Bob are equally matched ($N_A=N_B$ and $b=1$), does Alice have a strategy that can guarantee her no less than 50% winning probability, no matter how Bob plays?

Question 2: is there always a dominant strategy for Alice?


Note: question 2 is a stronger claim, and implies question 1. For $c=1$, I know the answersanswer is yes for both questions are yes, because in that case the game is essentially the gambler's ruin problem, so every strategy gives the same winning probability for Alice. I suspect but can't prove an equal distribution is dominant for $c=0$ and give-it-all-to-one is dominant for $c\gt1$. A simulation for $N_A=N_B=2$, $b=1$ and $c=1/2$ suggests that giving 0.420341... to the first warrior guarantees 50% winning probability for Alice.

Alice and Bob have $N_A$ and $N_B$ warriors under their command, numbered $1$~$N_A$ and $1$~$N_B$ respectively. Alice has $1$ fighting power at her disposal, and Bob has $b$ ($b\gt 0$). Before the game, they privately distribute their power between their warriors. When the game begins, both send their warrior #1 to a 1-to-1 fight. If a warrior with power $x$ fights one with power $y$, the former wins with probability $\frac{x}{x+y}$, and the latter with $\frac{y}{x+y}$. If #1 is defeated, #2 is sent to continue the next round of fight, so on and so forth until one side has all of their warriors defeated and loses the game. There's a small twist though: after a warrior defeats an $x$ power opponent, his power will increase by $cx$ ($c\geq 0$).

Clearly, a player's strategy is their method of distributing fighting power.

Question 1: given $N_A=N_B$ and $b=1$, does Alice have a strategy that can guarantee her no less than 50% winning probability, no matter how Bob plays?

Question 2: is there always a dominant strategy for Alice?


Note: question 2 is a stronger claim, and implies question 1. For $c=1$, I know the answers for both questions are yes, because in that case the game is essentially the gambler's ruin problem, so every strategy gives the same winning probability for Alice. I suspect but can't prove an equal distribution is dominant for $c=0$ and give-it-all-to-one is dominant for $c\gt1$. A simulation for $N_A=N_B=2$, $b=1$ and $c=1/2$ suggests that giving 0.420341... to the first warrior guarantees 50% winning probability for Alice.

Alice and Bob have $N_A$ and $N_B$ warriors under their command, numbered $1$~$N_A$ and $1$~$N_B$ respectively. Alice has $1$ fighting power at her disposal, and Bob has $b$ ($b\gt 0$). Before the game, they privately distribute their power between their warriors. When the game begins, both send their warrior #1 to a 1-to-1 fight. If a warrior with power $x$ fights one with power $y$, the former wins with probability $\frac{x}{x+y}$, and the latter with $\frac{y}{x+y}$. If #1 is defeated, #2 is sent to continue the next round of fight, so on and so forth until one side has all of their warriors defeated and loses the game. There's a small twist though: after a warrior defeats an $x$ power opponent, his power will increase by $cx$ ($c\geq 0$).

Clearly, a player's strategy is their method of distributing fighting power.

Question 1: if Alice and Bob are equally matched ($N_A=N_B$ and $b=1$), does Alice have a strategy that can guarantee her no less than 50% winning probability, no matter how Bob plays?

Question 2: is there a dominant strategy for Alice?


Note: question 2 is a stronger claim, and implies question 1. For $c=1$, I know the answer is yes for both questions, because in that case the game is essentially the gambler's ruin problem, so every strategy gives the same winning probability for Alice. I suspect but can't prove an equal distribution is dominant for $c=0$ and give-it-all-to-one is dominant for $c\gt1$. A simulation for $N_A=N_B=2$, $b=1$ and $c=1/2$ suggests that giving 0.420341... to the first warrior guarantees 50% winning probability for Alice.

Added question 1.
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Eric
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Alice and Bob have $N_A$ and $N_B$ warriors under their command, numbered $1$~$N_A$ and $1$~$N_B$ respectively. Alice has $1$ fighting power at her disposal, and Bob has $b$ ($b\gt 0$). Before the game, they privately distribute their power between their warriors. When the game begins, both send their warrior #1 to a 1-to-1 fight. If a warrior with power $x$ fights one with power $y$, the former wins with probability $\frac{x}{x+y}$, and the latter with $\frac{y}{x+y}$. If #1 is defeated, #2 is sent to continue the next round of fight, so on and so forth until one side has all of their warriors defeated and loses the game. There's a small twist though: after a warrior defeats an $x$ power opponent, his power will increase by $cx$ ($c\geq 0$).

Clearly, a player's strategy is their method of distributing fighting power.

Question 1: given $N_A=N_B$ and $b=1$, does Alice have a strategy that can guarantee her no less than 50% winning probability, no matter how Bob plays?

Question 2: is there always a dominant strategy for Alice?


NoteNote: forquestion 2 is a stronger claim, and implies question 1. For $c=1$, I know the answer isanswers for both questions are yes, because in that case the game is essentially the gambler's ruin problem, so every strategy gives the same winning probability for Alice. I suspect but can't prove an equal distribution is dominant for $c=0$ and give-it-all-to-one is dominant for $c\gt1$. A simulation for $N_A=N_B=2$, $b=1$ and $c=1/2$ suggests that giving 0.420341... to the first warrior dominates all other strategiesguarantees 50% winning probability for Alice.

Alice and Bob have $N_A$ and $N_B$ warriors under their command, numbered $1$~$N_A$ and $1$~$N_B$ respectively. Alice has $1$ fighting power at her disposal, and Bob has $b$ ($b\gt 0$). Before the game, they privately distribute their power between their warriors. When the game begins, both send their warrior #1 to a 1-to-1 fight. If a warrior with power $x$ fights one with power $y$, the former wins with probability $\frac{x}{x+y}$, and the latter with $\frac{y}{x+y}$. If #1 is defeated, #2 is sent to continue the next round of fight, so on and so forth until one side has all of their warriors defeated and loses the game. There's a small twist though: after a warrior defeats an $x$ power opponent, his power will increase by $cx$ ($c\geq 0$).

Clearly, a player's strategy is their method of distributing fighting power.

Question: is there always a dominant strategy for Alice?


Note: for $c=1$, I know the answer is yes, because in that case the game is essentially the gambler's ruin problem, so every strategy gives the same winning probability for Alice. I suspect but can't prove an equal distribution is dominant for $c=0$ and give-it-all-to-one is dominant for $c\gt1$. A simulation for $N_A=N_B=2$, $b=1$ and $c=1/2$ suggests that giving 0.420341... to the first warrior dominates all other strategies.

Alice and Bob have $N_A$ and $N_B$ warriors under their command, numbered $1$~$N_A$ and $1$~$N_B$ respectively. Alice has $1$ fighting power at her disposal, and Bob has $b$ ($b\gt 0$). Before the game, they privately distribute their power between their warriors. When the game begins, both send their warrior #1 to a 1-to-1 fight. If a warrior with power $x$ fights one with power $y$, the former wins with probability $\frac{x}{x+y}$, and the latter with $\frac{y}{x+y}$. If #1 is defeated, #2 is sent to continue the next round of fight, so on and so forth until one side has all of their warriors defeated and loses the game. There's a small twist though: after a warrior defeats an $x$ power opponent, his power will increase by $cx$ ($c\geq 0$).

Clearly, a player's strategy is their method of distributing fighting power.

Question 1: given $N_A=N_B$ and $b=1$, does Alice have a strategy that can guarantee her no less than 50% winning probability, no matter how Bob plays?

Question 2: is there always a dominant strategy for Alice?


Note: question 2 is a stronger claim, and implies question 1. For $c=1$, I know the answers for both questions are yes, because in that case the game is essentially the gambler's ruin problem, so every strategy gives the same winning probability for Alice. I suspect but can't prove an equal distribution is dominant for $c=0$ and give-it-all-to-one is dominant for $c\gt1$. A simulation for $N_A=N_B=2$, $b=1$ and $c=1/2$ suggests that giving 0.420341... to the first warrior guarantees 50% winning probability for Alice.

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Eric
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Is there a dominant strategy for this game?

Alice and Bob have $N_A$ and $N_B$ warriors under their command, numbered $1$~$N_A$ and $1$~$N_B$ respectively. Alice has $1$ fighting power at her disposal, and Bob has $b$ ($b\gt 0$). Before the game, they privately distribute their power between their warriors. When the game begins, both send their warrior #1 to a 1-to-1 fight. If a warrior with power $x$ fights one with power $y$, the former wins with probability $\frac{x}{x+y}$, and the latter with $\frac{y}{x+y}$. If #1 is defeated, #2 is sent to continue the next round of fight, so on and so forth until one side has all of their warriors defeated and loses the game. There's a small twist though: after a warrior defeats an $x$ power opponent, his power will increase by $cx$ ($c\geq 0$).

Clearly, a player's strategy is their method of distributing fighting power.

Question: is there always a dominant strategy for Alice?


Note: for $c=1$, I know the answer is yes, because in that case the game is essentially the gambler's ruin problem, so every strategy gives the same winning probability for Alice. I suspect but can't prove an equal distribution is dominant for $c=0$ and give-it-all-to-one is dominant for $c\gt1$. A simulation for $N_A=N_B=2$, $b=1$ and $c=1/2$ suggests that giving 0.420341... to the first warrior dominates all other strategies.