Coin tosses

[Jon Corby]

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.

[Matt Morrison]

Shall I help?

[Jon Corby]

Shall I help?

If you can, sure.

[Matt Morrison]

Shall I help?

If you can, sure.

Raccoon might be able to add to that.

[Jon O'Neill]

In a word,

[Jon Corby]

In a word,

MWM's made more sense to me.

[Gavin Chipper]

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 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.

You'd just do a two-tailed test and see what the statistical significance is.

[Gavin Chipper]

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.

[Jon Corby]

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.

Yeah, so if the coin was 55/45, how likely are we to see that result (of 137/228)?

[Charlie Reams]

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.

Yeah, so if the coin was 55/45, how likely are we to see that result (of 137/228)?

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.

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.

[Rhys Benjamin]

The coin may be heavier on the heads side.

[Charlie Reams]

The coin may be heavier on the heads side.

IQ of 136, don't forget.

[Joseph Krol]

The coin may be heavier on the heads side.

IQ of 136, don't forget.

162 which is higher than Carol V. So there.

[Ryan Taylor]

The coin may be heavier on the heads side.

IQ of 136, don't forget.

162 which is higher than Carol V. So there.

Yeah but she's a woman.

[Lesley Hines]

162 which is higher than Carol V. So there.

Yeah but she's a woman.

And therefore uses it

[Ryan Taylor]

162 which is higher than Carol V. So there.

Yeah but she's a woman.

And therefore uses it

What? The coin? In her slot? Filth.

[Soph K]

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.

No idea what you mean! I'm just a kid!!! I am in Set 1 Maths, but still!

[Kirk Bevins]

Yeah but she's a woman.

Good job you don't work for Sky.

[Kai Laddiman]

Yeah but she's a woman.

Good job you don't work for Sky.

That was the joke?

[Kirk Bevins]

That was the joke?

It can't have been as Ryan's not funny.

[Gavin Chipper]

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.

No idea what you mean! I'm just a kid!!! I am in Set 1 Maths, but still!

It turned out that he was talking rubbish anyway.

[Ryan Taylor]

That was the joke?

It can't have been as Ryan's not funny.

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.

[Peter Mabey]

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.