Talk:Parrondo's paradox

message: Note that the probability of game B is not (2/3)(3/4) + (1/3)(1/10) - ε, which is 16/30 - ε and might suggest that B is actually a winning game.
"Harmer and Abbott[1] show via simulation that if M = 3 and ε = 0.005, Game B is an almost surely losing game as well." I should like to point out that simulation cannot show that such a statement is true; it may well strongly suggest that Game B is almost surely losing but the only way to prove it is to, well, prove it. Surely a more accurate wording would be "Harmer and Abbott[1] simulate Game B with M = 3 and ε = 0.005 and the results strongly suggest that this is an almost surely losing game as well." If one wants a proof then (as Harmer and Abbott[1] say) one needs to look at "Parrondo’s Paradoxical Games and the Discrete Brownian Ratchet, Proceedings of Upon’99, The Second International Conference on Unsolved Problems of Noise and Fluctuations, University of Adelaide,  July 12-16, 1999, eds. D.A. Abbott and L.B. Kish, American Institute of Physics, Melville, New York 511 (2000) 189–200."  —Preceding unsigned comment added by 128.243.220.22 (talk) 10:58, 16 February 2009 (UTC)
thread_title:  The math second illustrative example 

message: I removed the following paragraph from the article:
:Parrondo's paradox can interestingly be expanded as an objection to the problem of evil. It is true by Parrondo's paradox that sequential negative events can result in a positive outcome, suggesting that the problem of evil may ignore such possibilities. Parrondo's paradox effectively allows every negative event to eventually have a positive outcome. Empirically, President Clinton's approval ratings rose above pre-scandal levels after his admission of his sex scandal with Monica Lewinsky. Both his sexual action and his admission could be seen as losing strategies regarding presidential approval ratings, but the American public saw his apology as an honorable deed, fulfilling Parrondo's Paradox.
First, I'm worried about whether it is orignal research.  It needs to be sourced if it is to be re-introduced.  Even if sourced, I think that they will make the article harder (rather than easier) to understand, because it introduces a confusion.  Parrondo's paradox is not paradoxical because of the simple addage "to wrongs don't make a right", it is rather more complex.  --best, kevin [kzollman][talk] 07:59, 16 April 2006 (UTC)
replies: text: I fully support what you did. I have not been able to keep update with the happenings of the page and saw the problem just now when you edited the talk page. Even I feel that the paragraph is Original Research. Parrando's Paradox should not be used to correlate events when no such justification exists. I don't know what to do with "agriculture" as it too is Original Research. There hasn't been any mathematical modelling of the phenomenon to establish a causation. Even if its true, the events are correlated, but causation is yet to be proved. -Ambuj Saxena (talk) 08:11, 16 April 2006 (UTC)
thread_title:  Problem of evil 

message: The article says:
:Given two games, each with a higher probability of losing than winning, it is possible to construct a winning strategy by playing the games alternately. 
it seems to me that it is not appropriate to say "each with a higher probability of losing than winning" because one of the games is allowed to have a probability of winning that in some case can be greater than the probability of losing.--Pokipsy76 (talk) 21:58, 18 February 2008 (UTC)
thread_title:  Stating the paradox 

message: If communication channels that Fail (carry 0 content), when working together in pairs could actually communicate a single bit of information.  Is this an example of a Parrondo's Paradox?
http://arxivblog.com/?p=554  —Preceding unsigned comment added by Rbenech (talk • contribs) 20:24, 2 January 2009 (UTC)
thread_title:  Quantum Communication: when 0 + 0 is not equal to 0 

message: When running a statistical test which returns number of played games under various conditions one realizes that all the 'paradox' does is change the ratio of played B1 and B2 games, which wins the 'B' game and offsets the small 'A' game loss.
Logically, if the winning game is played more often, the return is positive. 
In this case (game 'B1'=9%, 'B2'=74% winning chance), playing the 'B' game alone produces 39% 'B1' games and 61% 'B2' games which is unfavorable to chances and the 'B' game finishes at loss.
However when injecting almost neutral 'A' game, the ratio of 'B' games changes, so for example in the 'ABBAB' sequence 'B2' is played 72% of time (of 'B' games) which provides positive outcome.
I will leave it to mathematicians to make the proof of it, but no wonders here.
Besides and above all, the returns in the 'B' games are not proportional to chances, in which case the total return would be as expected (loss) regardless of the frequency and/or sequences of the played games.
For the above examples the return for individual games should be roughly: +49/-51 for the 'A' game; +89/-10 for 'B1' and +24/-76 for 'B2' game, which would put 'the paradox' where it belongs.
It is just amazing that such stuff can be a subject of academic researches. --activeco
:I doubt that it is. The article has a long reading list, but I wonder how many of the authors there take this "paradox" seriously. Maproom (talk) 22:32, 10 August 2011 (UTC)
thread_title:  Statistical observations of the 'paradox' 

message: Would make the concept much easier to grasp. --TiagoTiago (talk) 02:00, 22 November 2011 (UTC)
replies: text: The way it's written it's simply nonsense. Why should some marbles move to the valley towards A, up-slope and over a steeper edge, and none towards B? --Thrissel (talk) 22:38, 9 February 2012 (UTC)
thread_title:  Needs an animation showing how the alternating rachet ramp makes things go up 

message: Let us consider the following two games. Our start capital is an integer amount of Euros (€). The rules:
# Coin 1 is a (highly) biased coin that always makes us win. Coin 2 is a (highly) biased coin that always makes us lose.
# Winning a game earns us 1€ and losing requires us to surrender 2€.
# In Game C, we first determine if our capital is an even number. If it is, we toss Coin 1. If it is not, we toss Coin 2.
# In Game D, we first determine if our capital is an even number. If it is, we toss Coin 2. If it is not, we toss Coin 1.
It is easy to see that both games are losing games, with an average loss of 1€ per game, if played in a random sequence. The sequences (CCCCC...) and (DDDDD...) are even worse. But the sequence (CDCDCD...) wins!
We see that it is essential for the example that the earnings depend on the current capital. And that the current capital depends on which games were played before - in a very sophisticated way in the A and B example of the Article, and in a simple way here (odd = C before, even = D before).
--Peter Buch (talk) 12:52, 6 March 2012 (UTC)
thread_title:  Another coin-tossing example 

message: I have a problem with the statement: "Now consider the second case where we have a saw-tooth-like region between them. Here also, the marbles will roll towards either ends with equal probability"
This case is analagous to a sawtooth shaped potential surface in physics with an oscillating force applied, which is known as a "rocking ratchet". As suggested by the name, it leads to preferential motion in one direction. In this case, towards B. So the second case here is actually a losing game even before the whole setup is tilted, see the diagram and explanation on page two of this article:
IEEE Transactions on Applied Superconductivity 19 3698  — Preceding unsigned comment added by 130.130.37.84 (talk) 03:24, 22 May 2012 (UTC)
thread_title:  The sawtooth setup doesn't give equal probabilities 

message: Having read this twice I am, as the learned judge once said, "none the wiser". Unfortunately I am not even , as counsel retorted "No, just better informed".
What on earth does "There exist pairs of games, each with a higher probability of losing than winning, for which it is possible to construct a winning strategy by playing the games alternately." mean?  It only makes any sense if you already know what the paradox is about. Read it cold (as I did) and its gobbledygook.  Its a perfect example of the techies paradox - the summary is only understandable if you've already read the detail. (I made that up BTW)
Update: In fairness, having read it a third time prior to this edit, the light bulb does go on when reading the "simplified example" although it's still not obvious that there are any real life examples. (I think the "application" section basically says we haven't found one.)
I'm not qualified to edit this but I really do think sticking the simplified example at the top, re-writing the lede and perhaps simplifying the language in the non-technical paragraph would make the article more accessible.  212.74.5.11 (talk) 08:04, 1 July 2015 (UTC)
thread_title:  Pretty inaccessible article for most people