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balder

birthdays

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most apps that select random ports will select them in the range >=1024 <=65535. this means that there are 64512 ports for the program to guess. the likly hood of them both gettnig say port 1411 would be (1/64512)*(1/64512)=(1/4161798144). (you can correct my math now :)). however owing to the birthday paradox if you have more applications then two choosing random ports the probability of 2 programms picking the same port will start to become expenetialy lower.

About birthdays: There is not any paradox. Your birthday = ~ 9 months from... you guess. :D And as we put things so, the sexual activity is not evenly distributed through the year, so just the base is not 365 days :D

the paradox is a probability paradox. not a statistical groupings one. the paradox is better observed in its application at finding hash collitions known as a birthday attack. however i suspect you where just being facetious so ill let you off :)

Sorry if this is slightly "Adult Only". Please read it when you reach 18+/21+ years according to your country regulations.

Yes, I was semi facetious, but also semi-serious. Anyway, the first formula in Birthday Attack article cause a major memory leakage in my brain. My point was that, f. ex. in UK, 30% of the teenagers... guess again (results of a survey). Further it means that there is spontaneous attraction, which is more likely to appear during the warmer part of the year (less clothes, more going out, no school, etc.). So I will be really interested if smo can dig out the interval with most birthday coincidences. smile.gif If this period is X:Y, I'm pretty sure that X:Y - 9 months ~ May:August

Thought id take this off topic.

i just wanted to say that i agree with you. there will be a larger density of people born around febuary, macrh and april due to the somer and it wouldn' t suprise me if there was also a density around september and october due to the festive christmas period.

the birthday paradox is a mathimatical one and assumes birthdays will be distributed evernly accross all days. which you have correctly pointed out is not the case. hell i didn't come up with the idea of proving this paradox with birthdays :P.

Edited by balder

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geez wth? sorry i just didn't get the point about this paradox :) can you explain me?

See you,

Keine

Edited by Keine

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geez wth? sorry i just didn't get the point about this paradox :) can you explain me?

See you,

Keine

Well, in short, the paradox assumes that the birthdays are distributed evenly during the year, which I do not take as truth, due to "some" factors, described in my posts above. You can read more about the paradox in Google.

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Thought id take this off topic.

i just wanted to say that i agree with you. there will be a larger density of people born around febuary, macrh and april due to the somer and it wouldn' t suprise me if there was also a density around september and october due to the festive christmas period.

the birthday paradox is a mathematical one and assumes birthdays will be distributed evernly accross all days. which you have correctly pointed out is not the case. hell i didn't come up with the idea of proving this paradox with birthdays :D.

believe the point is more this

for some U(U = the Universe of numbers) between 0 - 366 where X = a birthday

f you were to choose a set such as the Sample set A {1,2,6,345,34,234,345} where A is a set of birthdays

then the chances that a new X pulled randomly from the Universe grows exponentially

Now follow this if you will... the Universe does allow for repetition as well thus you can have unevenly distributions.

so { xE A u U | ((365!/(365^x)((365-x)!} //this x is not X, this.x is number of people

so basically (and someone can correct my math if I made an error) the distribution doesn't matter

because over any large sets of data where your universe is from 0-366 the probability will = 100%.

Therefore your probability for a smaller Universe (Ie where you can account for smaller anomalies such as uneven distrubtions) would be different.. though it still would follow the same curve as the theory represents just the bounds however would your sample set (so from march to sept for example). In that case it would then only make it to 99.9% as you'd have to take in account the lack of data from outside of your set for it to be realistic but within the Unverse of march to sept the theory would still hold true. anyway I've rambled enough now.

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LOL - dont you have something more interesting to waste your time with ? :D it can be explained much more easy.No need for any math.

I cant get the purpose of this topic - if you all agree and all know it why make it ?

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LOL - dont you have something more interesting to waste your time with ? :D it can be explained much more easy.No need for any math.

I cant get the purpose of this topic - if you all agree and all know it why make it ?

quite clearly I was bored and didn't feel like studying for my math midterm anymore

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Topic was very misleading. :D No one really ses the higher ports so it's probably even more extreme than the birthday paradox as people are often and lazy and would put in less digits than the maximum possible so those high numbers will very rarely be choosen.

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Topic was very misleading. :D No one really ses the higher ports so it's probably even more extreme than the birthday paradox as people are often and lazy and would put in less digits than the maximum possible so those high numbers will very rarely be choosen.

very true, though I'm an odd ball and use the higher ports mainly cause they aren't restricted by my campus uni. haha

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If Greg's theory of laziness is right the range should be 1-9. :P

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If Greg's theory of laziness is right the range should be 1-9. :P

well it is write.... just that those are already reserved by the orignal lazy programmers :P

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believe the point is more this

..............

anyway I've rambled enough now.

thankyou for clearing that up for me, your obviously a bigger geek then me :P

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If Greg's theory of laziness is right the range should be 1-9. :P

IF?! THEORY?! It's pure fact. :P

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thankyou for clearing that up for me, your obviously a bigger geek then me ;)

no problem really I just don't want to do my java assignment or study for math... though I realize the irony of doing theorical math and not studying for it... but anyways glad to help out :P

EDIT:: Also horrible spelling on my part write == right haha :P

And Greg your location threw me for a loop haha I looked at it and thought you were from Surrey BC Canada 1st hehe which is near my home town haha

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