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First-order statistical battle

Imagine there is a game in which the user should guess what values the opponent is hiding from the user. In the first battle, the opponent has two hidden values a and b where a is the mean and b is the standard deviation (in a normal distribution). The rules of the game are:

  • User knows how the generation system works on the opponent's side.
  • User does not know what the a and b values are.
  • User can ask the opponent to generate a new value using the values a and b and show it to the user. The user can ask for a new number infinitely.

✅ Solution

In the first battle, the user wins. Because after generating so many numbers, the user eventually finds a and b or at least gets very close to them.

first order battle

Second-order statistical battle

Imagine a new game where the opponent hides four static values a, b, c, and d. The same rules of the previous game apply to this game, but instead of only a and b, they apply to c and d as well. In this battle, every time the user asks for a new number, the opponent first generates a new tuple (X=mean, Y=stdDev) where X is generated using a and b (a is mean and b is stddev) and Y is generated using c and d (c is mean and d is the stddev). The opponent then generates a new number using (X, Y) and sends it to the user. Can the user find out what those four values are eventually?

❓ Possible solution?

A potential solution that one might propose is to generate K numbers (where K is large enough) and then calculate the mean and stddev of these K numbers, let it be (X1, Y1). Then repeat this step and generate another K number and calculate a new tuple (X2, Y2). We repeat this until we have so many tuples of Xn and Yn. Then we can calculate a and b using all the Xn, and c and d using all the Yn.

second order battle

Questions of post

  1. Does the proposed solution work? Can the user find a, b, c, and d using this method?

  2. If that method doesn't work, can the user figure out what those four values are using any other approach?

Avestura
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