Correlation and causation...

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[XAP]Bob
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Correlation and causation...

Post by [XAP]Bob »

Spotted a few posts with the fact that correlation doesn't imply causation and then did a quick search on the forum for this link without success, so I thought I'd share it.

What's your favourite?

https://www.tylervigen.com/spurious-correlations


How's about:
"Bicyclists killed in collision with two- or three-wheeled motor vehicle" correlates very well with "Deaths caused by X-ray contrast media"...

http://tylervigen.com/view_correlation?id=239
Last edited by [XAP]Bob on 26 Nov 2021, 1:41pm, edited 1 time in total.
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
There are two kinds of people in this world: those can extrapolate from incomplete data.
Jdsk
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Re: Correlation and causation...

Post by Jdsk »

Very good.

There used to be a famous one about the number of Church of England vicars and something... but I can't remember what. : - (

Jonathan
thirdcrank
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Re: Correlation and causation...

Post by thirdcrank »

Perhaps the skill involves recognising when it's not spurious eg when both are related and share a common cause. The value of that skill lies in then being able to try to influence the effects.
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[XAP]Bob
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Re: Correlation and causation...

Post by [XAP]Bob »

The famous example being the suggestion that yellow teeth caused lung cancer.
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
There are two kinds of people in this world: those can extrapolate from incomplete data.
oldtimer99
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Re: Correlation and causation...

Post by oldtimer99 »

In a past life, I taught this stuff. A favourite session to invoke the causation conversation was to correlate sales of chewing gum with number of teenage pregnancies....this was in the early 80's
Strong positive correlation, and obviously pregnancy causes one to chew gum. Or vice versa
rotavator
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Re: Correlation and causation...

Post by rotavator »

It reminds me of an A level General Studies question about the geographic correlation between the incidence of potato blight and neural tube defects, i.e. spina bifida etc.
Stradageek
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Re: Correlation and causation...

Post by Stradageek »

Jdsk wrote: 26 Nov 2021, 1:40pm Very good.

There used to be a famous one about the number of Church of England vicars and something... but I can't remember what. : - (

Jonathan
There was (apocryphally) a strong positive correlation between the wages of Scottish Presbyterian Church Ministers and the number of registered prostitutes in Rio-de-Janeiro.
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mjr
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Re: Correlation and causation...

Post by mjr »

Our standard example at uni used to be the strong negative correlation between annual UK alcohol consumption and infant mortality: drink more to save babies!
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Mike Sales
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Re: Correlation and causation...

Post by Mike Sales »

I notice that two of the three killed by trees in Storm Arwen were in cars.
A police car at one of the scenes was also crushed.
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It's the poor what gets the blame
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[XAP]Bob
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Re: Correlation and causation...

Post by [XAP]Bob »

That doesn't surprise me all that much - I could reasonably expect a causative explanation for that.

- Heavy storm, so people not likely to be out walking
- Therefore people are generally either in a car or in a house
- Houses are better protection, and much less likely to be under a big tree

Out of interest - where was that third person?
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
There are two kinds of people in this world: those can extrapolate from incomplete data.
Mike Sales
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Re: Correlation and causation...

Post by Mike Sales »

[XAP]Bob wrote: 2 Dec 2021, 3:39pm That doesn't surprise me all that much - I could reasonably expect a causative explanation for that.

- Heavy storm, so people not likely to be out walking
- Therefore people are generally either in a car or in a house
- Houses are better protection, and much less likely to be under a big tree

Out of interest - where was that third person?
Yes, indeed. That had occurred to me!
A headteacher in Northern Ireland died after a tree fell on his car, another man was hit by a falling tree in Cumbria, and a third died after his car was hit in Aberdeenshire.
Last edited by Mike Sales on 2 Dec 2021, 3:46pm, edited 1 time in total.
It's the same the whole world over
It's the poor what gets the blame
It's the rich what gets the pleasure
Isn't it a blooming shame?
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[XAP]Bob
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Joined: 26 Sep 2008, 4:12pm

Re: Correlation and causation...

Post by [XAP]Bob »

Cumbria - well that strictly answers the question I asked :lol: :roll:
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
There are two kinds of people in this world: those can extrapolate from incomplete data.
PDQ Mobile
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Re: Correlation and causation...

Post by PDQ Mobile »

Does that mean if we cut down all trees (as sometimes suggested on here) that storm fatalities could be reduced to almost zero?
:shock:
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Mick F
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Re: Correlation and causation...

Post by Mick F »

Yep.
Trees are dangerous things in the wind. I won't go into our woods when it's windy.

I read that due to Ash Dieback, they are giving away trees for free.
All very laudable, but where are they planting them?

https://www.bbc.co.uk/news/uk-england-devon-59503256
Mick F. Cornwall
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RickH
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Re: Correlation and causation...

Post by RickH »

Former member of the Cult of the Polystyrene Head Carbuncle.
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