"one of them" != "one and only one of them", plus that's the only way the question is of any interest, otherwise the answer would be "well, zero, duh".
The correct expression is: P(H¦H)=P(HH)/(P(HH)+P(HT)) = (1/4)/((1/4)+(1/2)) = 1/3.
also:
There are four equally likely outcomes: HH, HT, TH, TT. The last must be excluded as we know that at least one is a head. That leaves HH, HT, TH. So there is a 1/3 chance of HH.
or
The real question, which is disguised within the scenario, is "What is the probability getting two heads?" The statement, "one of the coins came up heads," means ONLY that TT did not happen.
You can try it at home: flip 2 coins, and when you find one that is heads, look if the other one is also heads. Tally. Repeat a bunch of times for the results to be significant.
I'm not assuming anything, just reading the question correctly: The question is NOT "if I flip two coins and THE FIRST ONE is heads..." (answer would then indeed be 50%), but "If I flip two coins and ONE OF THEM is heads..."
I'm listing all 4 combinations for 2 flips, and out of the 3 that satisfy the prerequisite ("one of them is heads") counting how many combinations turn up with the other one also being heads. There's one out of 3 possibilities, so that's 33%.
the problem would then read "if I flip 2 coins and the first one is heads, what is the probability the second one will be heads too ?", not "If I flip two coins and one of them is heads, what are the odds the other one is also heads ?".
whatever his professionnal skills, I just hope I never have to work alongside a guy with such a foul mouth and attitude.
I did manage to hang on long enough to see that below the big "I'm a jerk" sign, there was at least some truth to his argument. Not that original or that strong to warrant such a hissy fit though.
the real question is: what's worse - the swearing ? - the attitude towards others ? - the ego ? - the lack of perspective ?
that guy should tone down the statistics skills and brush up on his social ones. Maybe we could send him a guide:
"fucking idiots devs need to do good like me myself I do, and stop swearing and belittling others like the foul-mouthed idiot fuckers they are they are and learn some modesty, politeness, and perspectve like my godly self, otherwise the world is gonna END !!!!!!"
1- stuff you choose to put online. There may be a bit of an expectation of privacy there (only my friends should see some of my facebook), but even then you're taking the risk to trust a third party to enforce some privacy for you. I'm fairly sure facebook and co commit to NOTHING regarding the safety, privacy... of your data, but that most people do not realize it.
2- stuff you broadcast unintentionally. My brother uses gmail and is into mountain climbing and Canada... all the Google ads on his Mac are about these 2 subjects.I got treated to 2 days of Monster Cables ads last time I looked for a cable (hint for google: once I'Ive bought a cable, these adds become irrelevant). I'm sure most people expect privacy, they do not realize that their every move on the web is tracked. Pretty much like carrying a GPS tracker + mike + being filmed at all times.
3- stuff that gets taken from a private place, be it my PC or my home. full expectation of privacy there, and clearly criminal to take it.
We French have a law (roughly called "IT and privacy) that guarantees us the right to see and amend any data about us retained in computer form. I'm of half a mind to request my file from google, for curiosity's sake.
only to find out that an allergy to peanuts is a side effect of a high resistance to that alien virus, had have to rush all over earth to locate people who survived the massacre.
I use my computer screen both for "computer" stuff and for video. That means I move it regularly, from my desk to my couch-potatoeing area. I'd love to have fewer or no cables snaking through my apartment. So cat6 does not solve my problem.
Intel's stuff doesn't either though. At $100 per screen plus I presume more or less the same on the PC side, I might as well buy an old PC or console to serve as a video player.
one could talk about an x86 monopoly, which is a weird instruction set, based on a weird CPU architecture. Though the architecture has by now been mostly microcoded away, it makes me sick every time I see x86 assembly code. Even Intel thinks they can do better now, but their RISC and later VLIW efforts failed in the face of x86-entrenchedness (trying to match x86 assembly ugliness with that word !)
there's also a kind of directX graphics monopoly: though ATI and nVidia go about implementing it in different ways, basically all they do is target directX, which does simplify things for developpers but prevents really innovating designs. OpenGL is tacked on as an afterthought, but all openGL seems to do these days is play catch-up.
I think commenting is a communication, rather than technical, skill. Some programmers may not be skilled at it, others better, independently of their programming skills. It requires being able to empathize with the reader, and pedagogy.
It's not "impose harsher restrictions to prevent that specific type of attack", it's "impose very visible restrictions that look to clueless voters like they will prevent that specific type of attack"
Let's wait and see what happens to the Kindle once PixelQi's screens become widely available.
I for one am looking for a one size fits all pda/phone/ebook/MIB/media player, possible the dell streak. No way I'm carrying along 4-5 items if one can do everything reasonnably well.
Slashdot Mirror
"one of them" != "one and only one of them", plus that's the only way the question is of any interest, otherwise the answer would be "well, zero, duh".
copied from the web:
The correct expression is:
P(H¦H)=P(HH)/(P(HH)+P(HT)) = (1/4)/((1/4)+(1/2)) = 1/3.
also:
There are four equally likely outcomes: HH, HT, TH, TT. The last must be excluded as we know that at least one is a head. That leaves HH, HT, TH. So there is a 1/3 chance of HH.
or
The real question, which is disguised within the scenario, is "What is the probability getting two heads?" The statement, "one of the coins came up heads," means ONLY that TT did not happen.
This leaves three possibilities: HT, TH, HH.
HH has a probability of .3333"
you're saying that in the "tails-heads" situation, you don't satisfy the "one of them is heads" prerequisite ?"
and that in the "tails-tails" situation, you do ?
that one, too.
You naysayers made me check my answer on the interweb. I'm right. Which is kinda funny: your horrified reactions... apply to yourselves :-)
2 coins, 2 states for each coin... it's very easy to build the combinatory tree I built.
I think you guys are misreading the question.
You can try it at home: flip 2 coins, and when you find one that is heads, look if the other one is also heads. Tally. Repeat a bunch of times for the results to be significant.
I'm not assuming anything, just reading the question correctly: The question is NOT "if I flip two coins and THE FIRST ONE is heads..." (answer would then indeed be 50%), but "If I flip two coins and ONE OF THEM is heads..."
I'm listing all 4 combinations for 2 flips, and out of the 3 that satisfy the prerequisite ("one of them is heads") counting how many combinations turn up with the other one also being heads. There's one out of 3 possibilities, so that's 33%.
the problem would then read "if I flip 2 coins and the first one is heads, what is the probability the second one will be heads too ?", not "If I flip two coins and one of them is heads, what are the odds the other one is also heads ?".
whatever his professionnal skills, I just hope I never have to work alongside a guy with such a foul mouth and attitude.
I did manage to hang on long enough to see that below the big "I'm a jerk" sign, there was at least some truth to his argument. Not that original or that strong to warrant such a hissy fit though.
the real question is: what's worse
- the swearing ?
- the attitude towards others ?
- the ego ?
- the lack of perspective ?
that guy should tone down the statistics skills and brush up on his social ones. Maybe we could send him a guide:
"fucking idiots devs need to do good like me myself I do, and stop swearing and belittling others like the foul-mouthed idiot fuckers they are they are and learn some modesty, politeness, and perspectve like my godly self, otherwise the world is gonna END !!!!!!"
he said "one of them", not "the first one" nor "the second one", so, really, "any one of them"... what do YOU come up with ?
true too, trickster !
I'm sure it's not 50%, and not 25%
heads=1, tails = 0
0-0 0-1 1-0 1-1
so if one of them is 1, there's a 33.33% chance the other is 1 too.
i can work it out that way for 2 binary possiblities. couldn't generalize it x coins possiblities with y sides :-/
good idea. I don' know if a screen can be transparent and touch-enabled at the same time though ?
1- stuff you choose to put online. There may be a bit of an expectation of privacy there (only my friends should see some of my facebook), but even then you're taking the risk to trust a third party to enforce some privacy for you. I'm fairly sure facebook and co commit to NOTHING regarding the safety, privacy... of your data, but that most people do not realize it.
2- stuff you broadcast unintentionally. My brother uses gmail and is into mountain climbing and Canada... all the Google ads on his Mac are about these 2 subjects.I got treated to 2 days of Monster Cables ads last time I looked for a cable (hint for google: once I'Ive bought a cable, these adds become irrelevant). I'm sure most people expect privacy, they do not realize that their every move on the web is tracked. Pretty much like carrying a GPS tracker + mike + being filmed at all times.
3- stuff that gets taken from a private place, be it my PC or my home. full expectation of privacy there, and clearly criminal to take it.
We French have a law (roughly called "IT and privacy) that guarantees us the right to see and amend any data about us retained in computer form. I'm of half a mind to request my file from google, for curiosity's sake.
only to find out that an allergy to peanuts is a side effect of a high resistance to that alien virus, had have to rush all over earth to locate people who survived the massacre.
gitmo ?
for $2M, I'll screw myself too.
I use my computer screen both for "computer" stuff and for video. That means I move it regularly, from my desk to my couch-potatoeing area. I'd love to have fewer or no cables snaking through my apartment. So cat6 does not solve my problem.
Intel's stuff doesn't either though. At $100 per screen plus I presume more or less the same on the PC side, I might as well buy an old PC or console to serve as a video player.
I don't quite agree with the "similar capabilities" and "unknown possibilities" part. To me, Android means
- physical keyboard, if I want one
- ability to freely install any software
- bigger screen
- non-emasculated bluetooth stack
- VOIP
- Flash
Not "similar", and not "unknown". Not just fresh paint and marketing gimmicks.
i find his political bid to try and get it back rather greedy.
one could talk about an x86 monopoly, which is a weird instruction set, based on a weird CPU architecture. Though the architecture has by now been mostly microcoded away, it makes me sick every time I see x86 assembly code. Even Intel thinks they can do better now, but their RISC and later VLIW efforts failed in the face of x86-entrenchedness (trying to match x86 assembly ugliness with that word !)
there's also a kind of directX graphics monopoly: though ATI and nVidia go about implementing it in different ways, basically all they do is target directX, which does simplify things for developpers but prevents really innovating designs. OpenGL is tacked on as an afterthought, but all openGL seems to do these days is play catch-up.
I think commenting is a communication, rather than technical, skill. Some programmers may not be skilled at it, others better, independently of their programming skills. It requires being able to empathize with the reader, and pedagogy.
You're being optimistic.
It's not "impose harsher restrictions to prevent that specific type of attack", it's "impose very visible restrictions that look to clueless voters like they will prevent that specific type of attack"
Let's wait and see what happens to the Kindle once PixelQi's screens become widely available.
I for one am looking for a one size fits all pda/phone/ebook/MIB/media player, possible the dell streak. No way I'm carrying along 4-5 items if one can do everything reasonnably well.