Coin tosses
Moderator: Jon O'Neill
Coin tosses
Some proper statsy business here, so I guess I'm mainly looking for Raccoon Boy, but if you know then dive in.
Say you have a coin. You do 228 tosses, and 60% come up heads.
What does this tell us about the coin?
e.g., how confident can we be the coin is actually 60/40 biased in favour of heads. What are the chances of it being 50/50? What about 55/45? etc. What would you say about the sample size?
Cheers.
Say you have a coin. You do 228 tosses, and 60% come up heads.
What does this tell us about the coin?
e.g., how confident can we be the coin is actually 60/40 biased in favour of heads. What are the chances of it being 50/50? What about 55/45? etc. What would you say about the sample size?
Cheers.
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Re: Coin tosses
Shall I help?
Re: Coin tosses
If you can, sure.Matt Morrison wrote:Shall I help?
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Re: Coin tosses
Jon Corby wrote:If you can, sure.Matt Morrison wrote:Shall I help?
Raccoon might be able to add to that.
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Re: Coin tosses
In a word,
Re: Coin tosses
MWM's made more sense to me.Jon O'Neill wrote:In a word,
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Re: Coin tosses
You can't say. There's no answer. You need to have a prior probability. Stattos talk about confidence intervals but that's not the same as saying that there is a certain chance.Jon Corby wrote:Some proper statsy business here, so I guess I'm mainly looking for Raccoon Boy, but if you know then dive in.
Say you have a coin. You do 228 tosses, and 60% come up heads.
What does this tell us about the coin?
e.g., how confident can we be the coin is actually 60/40 biased in favour of heads. What are the chances of it being 50/50? What about 55/45? etc. What would you say about the sample size?
Cheers.
You'd just do a two-tailed test and see what the statistical significance is.
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Re: Coin tosses
We'll call it 137 out of 228. I make the significance 0.0028, or however you phrase it. Basically if the coin is fair, such a result or more freaky would happen about 0.28% of the time. About 1 in 360. A degree.
Re: Coin tosses
Yeah, so if the coin was 55/45, how likely are we to see that result (of 137/228)?Gavin Chipper wrote:We'll call it 137 out of 228. I make the significance 0.0028, or however you phrase it. Basically if the coin is fair, such a result or more freaky would happen about 0.28% of the time. About 1 in 360. A degree.
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Re: Coin tosses
Slim. But the chance of any single outcome with that many repetitions is very slim. If you did a million trials with a perfectly fair coin, you'd still be extremely surprised to see it come out 500k/500k.Jon Corby wrote:Yeah, so if the coin was 55/45, how likely are we to see that result (of 137/228)?Gavin Chipper wrote:We'll call it 137 out of 228. I make the significance 0.0028, or however you phrase it. Basically if the coin is fair, such a result or more freaky would happen about 0.28% of the time. About 1 in 360. A degree.
But what Gevin said originally is correct, there's no a priori way to answer your question. All you can do is propose a hypothesis and see how consistent it is with the data.
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Re: Coin tosses
The coin may be heavier on the heads side.
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Re: Coin tosses
IQ of 136, don't forget.Rhys Benjamin wrote:The coin may be heavier on the heads side.
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Re: Coin tosses
162 which is higher than Carol V. So there.Charlie Reams wrote:IQ of 136, don't forget.Rhys Benjamin wrote:The coin may be heavier on the heads side.
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Re: Coin tosses
Yeah but she's a woman.Joseph Krol wrote:162 which is higher than Carol V. So there.Charlie Reams wrote:IQ of 136, don't forget.Rhys Benjamin wrote:The coin may be heavier on the heads side.
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Re: Coin tosses
And therefore uses itRyan Taylor wrote:Yeah but she's a woman.Joseph Krol wrote:162 which is higher than Carol V. So there.
Lowering the averages since 2009
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Re: Coin tosses
What? The coin? In her slot? Filth.Lesley Hines wrote:And therefore uses itRyan Taylor wrote:Yeah but she's a woman.Joseph Krol wrote:162 which is higher than Carol V. So there.
Re: Coin tosses
No idea what you mean! I'm just a kid!!! I am in Set 1 Maths, but still!Jon Corby wrote:Some proper statsy business here, so I guess I'm mainly looking for Raccoon Boy, but if you know then dive in.
Say you have a coin. You do 228 tosses, and 60% come up heads.
What does this tell us about the coin?
e.g., how confident can we be the coin is actually 60/40 biased in favour of heads. What are the chances of it being 50/50? What about 55/45? etc. What would you say about the sample size?
Cheers.
One Direction are my life. <3
"The reason for life is to find out who you are"
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"The reason for life is to find out who you are"
"It always seems impossible until it's done"
Love loads of celebs to be honest... Might marry Nicky Maccy
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Re: Coin tosses
Good job you don't work for Sky.Ryan Taylor wrote: Yeah but she's a woman.
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Re: Coin tosses
That was the joke?Kirk Bevins wrote:Good job you don't work for Sky.Ryan Taylor wrote: Yeah but she's a woman.
16/10/2007 - Episode 4460
Dinos Sfyris 76 - 78 Dorian Lidell
Proof that even idiots can get well and truly mainwheeled.
Dinos Sfyris 76 - 78 Dorian Lidell
Proof that even idiots can get well and truly mainwheeled.
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Re: Coin tosses
It can't have been as Ryan's not funny.Kai Laddiman wrote: That was the joke?
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Re: Coin tosses
It turned out that he was talking rubbish anyway.Soph K wrote:No idea what you mean! I'm just a kid!!! I am in Set 1 Maths, but still!Jon Corby wrote:Some proper statsy business here, so I guess I'm mainly looking for Raccoon Boy, but if you know then dive in.
Say you have a coin. You do 228 tosses, and 60% come up heads.
What does this tell us about the coin?
e.g., how confident can we be the coin is actually 60/40 biased in favour of heads. What are the chances of it being 50/50? What about 55/45? etc. What would you say about the sample size?
Cheers.
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Re: Coin tosses
It's OK Coke, I'll pretend that it wasn't the joke to make you a little happier after being displaced as top dog of anagrams.Kirk Bevins wrote:It can't have been as Ryan's not funny.Kai Laddiman wrote: That was the joke?
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Re: Coin tosses
I see the Royal Mint are producing a £5 coin this year to commemorate the Duke of Edinburgh's birthday with his head on one side and the Queen's on the other.