SIMPSON

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SIMPSONS PARADOX
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Simpsons ParadoxA and B represent two
treatments for a terrible disease. In the
following study 26 people with this disease were
treated. Some chose treatment A, others chose B.
The following data was collected.

• 1 man treated with A recovered.
• 4 men treated with A did not recover.
• 4 women treated with A recovered.
• 5 women treated with A did not recover.

• 3 men treated with B recovered.
• 7 men treated with B did not recover.
• 1 woman treated with B recovered.
• 1 woman treated with B did not recover.

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Treatment A
Treatment B
Cure rate3/1030
Cure rate 1/520
Cure rate1/250
Cure rate4/944
Treatment B has a higher cure rate for men
AND Treatment B has a higher cure rate for women.
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Treatment A
Treatment B
Cure rate3/1030
Cure rate 1/520
B has a higher cure rate for men
Cure rate1/250
Cure rate4/944
B has a higher cure rate for women
5 of the total number of 14 people treated with
A survived. Cure rate5/1436
4 of the total number of 12 people treated with
B survived. Cure rate4/1233
But A has a higher cure rate overall !
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A MOST INGENIOUS PARADOX