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1. 

   Fazookus, 8 Jan 2004 @ 6:52pm

   
   

   Storm Warning...

   
   Cheap shot!! Accurate, but none the less cheap ;->

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2. 

   dorpus, 9 Jan 2004 @ 3:56am

   
   

   A math problem most doctors got wrong:

   from an article in the Financial Times:
   
   About 1 per cent of women have breast cancer and a cancer screening method can detect 80 per cent of genuine cancers but also has a false-alarm rate of 10 per cent. What is the probability that women producing a positive result really have breast cancer? Most doctors reckoned it was at least 70 per cent.
   
   
   The correct answer, found by only two doctors, is just 8 per cent.
   
   

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3. 

   DL, 9 Jan 2004 @ 6:08am

   
   

   Re: A math problem most doctors got wrong:

   7.5%, I think.
   
   Picture an initial sample of 1000 women. 10 have breast cancer. Out of the 990 who do not, the 10% false alarm rate means the test will show 99 positives. Out of the 10 women who have breast cancer, the 80% detection rate means the test will show 8 positives. So, after testing 1000 women the test shows 107 positives. Only 10 women have breast cancer, but only 8 of the positive test patients have breast cancer. 8 out of 107 is 7.5% (or, more precisely, but still not exact: 7.48%).
   
   Nit-picking, I know. But as long as you're talking about getting a math problem wrong...
   

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4. 

   Mike (profile), 9 Jan 2004 @ 9:30am

   
   

   Re: A math problem most doctors got wrong:

   I have no idea what this has to do with the particular post, but it looks like a standard Simpson's paradox situation, which are fairly common, but always seem to amaze those who never took a statistics class.

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5. 

   annon, 29 Jan 2007 @ 12:30pm

   
   

   Classic errors and fallacies

   They have no excuse for getting that problem wrong, it is a fairly high profile piece of mandatory teaching in medical school. If you get it wrong in a oral exam, you can expect to repeat the the course.
   
   That said, a senior professor very publicly got a related problem wrong as an expert witness in the UK, and more than a dozen women were wrongly jailed for their cot death babies.....
   
   but then the same problem is taught as the cause of a classic fallacy in law school, so the defence lawyers and presiding judges have something to explain too...
   
   
   The false storm warning is a different classic error : not checking your sources. Something which matters ever more when sites crib from each other, the net can become an engine of misinformation

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