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Comment: Re:Not many devices (Score 3, Interesting) 56

by Reaper9889 (#49409041) Attached to: How To Make a Bitcoin Address With a TI-89 Calculator

Well, that was one of the more unexpected "you mama" joke: Your mama is so fat that she shows up in a post mentioning only your room!

I want to note that just in case someone thinks so: You can not roll two 6-sided die and add them together and get a 12-sided dice - first of all you cant roll 1 and you roll 7 way too often. What you can do is have two rolls of a 6-sided die. Say you first roll x and then y. If y is even you rolled x otherwise you rolled 6+x. This gives you precisely 12 different equally likely outcomes.

Comment: Re:Black and White (Score 1) 177

by Reaper9889 (#49348917) Attached to: German Auto Firms Face Roadblock In Testing Driverless Car Software

So a pedestrian is walking on the sidewalk 10m from your car. Do you slow down? If not, how will you avoid hitting him if he suddenly decides to sprint and jump infront of your car? If you do slow down, people will never use the autodrive feature.

You could write it under the assumption that everybody else was trying to make you fail (basically it would become a zero-sum game) but it is fairly clear that it is far too restrictive in any real sense.

Comment: Re:People (Score 2) 216

by Reaper9889 (#49285513) Attached to: France Will Block Web Sites That Promote Terrorism

While I agree that stopping terrorists are important, there are things worse than that. Removing our freedoms (like here: freedom of religion) seemes to me to be one of them. It is reasonable to prevent people from aiding violent extremists of any kind, but there is little link between that and islam. I.e. there are over 1bn muslims. How many muslim terrorist have we seen the last 50 years? If it is not more than 100,000 (which seems magnitudes too large), that is still less than 0.01% which is basically just a rounding error.

Comment: Obg. Douglas Adams quote (Score 2) 186

by Reaper9889 (#48518677) Attached to: Pizza Hut Tests New "Subconscious Menu" That Reads Your Mind

“After a fairly shaky start to the day, Arthur's mind was beginning to reassemble itself from the shell-shocked fragments the previous day had left him with.
He had found a Nutri-Matic machine which had provided him with a plastic cup filled with a liquid that was almost, but not quite, entirely unlike tea.
The way it functioned was very interesting. When the Drink button was pressed it made an instant but highly detailed examination of the subject's taste buds, a spectroscopic analysis of the subject's metabolism and then sent tiny experimental signals down the neural pathways to the taste centers of the subject's brain to see what was likely to go down well. However, no one knew quite why it did this because it invariably delivered a cupful of liquid that was almost, but not quite, entirely unlike tea.”

Comment: Plague, inc. (Score 1) 475

by Reaper9889 (#48031087) Attached to: Ebola Has Made It To the United States

Good news: after running extensive realistic experiments using the well known disease simulator plague, inc. I can conclude that the probaility that ebola will successfully annihilate humanity is quite low (because it didnt spread first and then ramped up the mortality which seemes to be one of the only really winning strategies)! The bad news is that now might be a good idea to move to Greenland since it could still destroy everything else :(

Comment: Re:meh (Score 2) 164

by Reaper9889 (#47670065) Attached to: Giant Greek Tomb Discovered

I think your point count against you. /. is fairly large. It would be reasonable to apply the same standards as for a large business. Hence, you should standardize your communication. In this case that means English and metric. It is ok that you use it amongst yourself but it would be nice of you to try to keep it only amongst yourself :) The standard custom in Europe is more or less that if someone wouldnt understand otherwise, you speak English (at least for the larger places I have worked). Similarly, it would be nice if you wrote in metric if people wouldn't understand otherwise (which I think it can be assumed that some wont on a page as big as /.).

I personally do not mind yards and feet too much but I dislike miles since it depends on the country.

Comment: Re:Solution (Score 1) 167

by Reaper9889 (#46682127) Attached to: A Rock Paper Scissors Brainteaser

The question isnt how much you bet against his bet but how much you are willing to pay him to play a given game with a fixed value for the outcomes (i.e winning losing and tieing). Note this is different from a bet in exactly the way you mention with the 3rd player, except that you pay your oppeont and not someone else - i.e you lost your payment even if you tie.

If you win 75% and him the rest and you get 1 for win 0 for tie and 1 for lose, you get 1 with 75% chance and lose 1 with 25% chance (0.5 on average) and should then be willing to give him upto 0.5 before playing the game because you then come up even (equvialently the game is fair/even if you get 0.5 for winning (1 minus the 0.5 you paid upfront), -0.5 for tieing and -1.5 for losing). Similarly if you pay him 0.5 and you win 1 with 50% chance and tie and get 0 with the remaning you are still even.

Game theory theories are math theories and not physics theories. Building on some given assumptions (i.e. what we measure is what you are willing to pay upfront) the theories are correct (if we look away from posible errors in the proofs - that said this is von Neumanns normal form games we are looking at right now and the proofs are correct under the assumptions used).

Comment: Re:Solution (Score 1) 167

by Reaper9889 (#46679153) Attached to: A Rock Paper Scissors Brainteaser

Not really :) The idea is that you subtract his winnings from yours (in the game you get the same for winning as he get) and not divide them. And both 1/2-1/3 and !/3-1/6 is equal to 1/6. Note that you do not replay if you both get the same but the game is instead a draw (this is not explicitly mentioned as far as I can see, but it is what is meant). Replaying the game makes it somewhat more complicated (which is why he must mean draw in case of ties - he seems to want an analytical solution you can do by hand). An exact solution in case of replaying on ties can be found by modeling the game as a stochastic game ala. Everett (you need to define what happens if you keep on replaying infinitely many times though) and then solve it fast using some algorithm in Kristoffer Arnsfelt Hansen, Michal Koucký, Niels Lauritzen, Peter Bro Miltersen, Elias P. Tsigaridas: Exact Algorithms for Solving Stochastic Games. I am currently writing a paper on an alternate, simpler way of solving such games, but it is not done yet :(

Comment: Re:Solution (Score 1) 167

by Reaper9889 (#46674845) Attached to: A Rock Paper Scissors Brainteaser

Say you increase to paper 2/3 - x and rock 1/3 + x. Then against paper 50% you win 1/3 - x/2 of the time and he wins 1/6+ x/2 of the time. Hence you get 1/6 - x on avg. On the other hand against scissors 50% you win 1/2 of the time (after having picked yours he got one option which is losing and he play each with 50%) and he wins 1/3 -x/2 of the time for 1/6-x/2. Finding the x that maximizes the smallest is easy. It is x=0. Note that you get 1/6 against the strategy I mentioned for the other guy because you do not do anything really stupid (= scissors). Also, note that maximizing the smallest is the most important thing if he is smart enough to figure out your strategy (since he will answer with the strategy leading to the smallest nr.)

Comment: Re:Two Games (Score 1) 167

by Reaper9889 (#46671947) Attached to: A Rock Paper Scissors Brainteaser

Ok lets see: you play 2/3 paper (I shorten the fraction I hope that is ok :) ) and 1/6 scissors and 1/6 rock. You play against the strategy 1/2 rock, 1/3 scissors, 1/6 paper. Fast version: lets look at a random round in which you play rock: In those you win 1/3 against his scissors and lose 1/6 against paper, thus you get 1/6 on avg.
Next, random round in which you play paper: In those you get 1/2 against his rock, and lose 1/3 against his scissors, i.e. again you gain 1/6.
Next, random round in which you play scissors: In those you get 1/6 against his paper and lose 1/2 against his rock, i.e. you LOSE 1/3.
On avg you play rock 2/3 of the time and get 1/6 in those rounds, scissors in 1/6 of the time and LOSE 1/3 and paper 1/6 of the time and get 1/6. Thus, on avg. 2/3*1/6+1/6*(-1/3)+1/6*1/6=1/12. This is below your lower bound so there is something wrong with it. (the reason is that you lose whenever a bit on avg. whenever you do not play paper).

My strategies, played against each other gives 1/6. Thus, you can not say that yours is better always. I can argue that against ANY strategy mine gets 1/6. You can not get better than 1/12 (because you get that against mine strategy for the other player). Thus, yours can not be optimal sorry :(

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