Capricorns crash through




For these questions use the article and the data set below.

AAMI Data Set: Policy holders and percentage accident rate by Star Sign

 

 Males

Females

 Star Sign

Policy Holders 

Accident Rate 

Policy Holders 

Accident Rate 
 Aquarius 35,666 14.33 22,067 14.69
Aries 37,926 13.93 22,959 15.13
Cancer 38,126 13.78 23,329 14.67
Capricorn 54,906 14.82 33,720 15.37
Gemini 37,179 14.02 22,587 14.57
 Leo 37,354 13.91 22,747 15.00
Libra 37,910 14.04 22,755 14.58
Pisces 36,677 13.90 21,967 14.95
Sagittarius 34,175 13.70 20,928 14.73
Scorpio 35,352 14.34 21,407 14.95
Taurus 37,179 14.32 22,715 14.85
Virgo 37,718 13.70 23,133 14.41

  1. Are the numbers of clients in each astrological sign nearly uniform across the year? (You can test this with a Chi-square test of goodness of fit to a uniform distribution).
  2. Why do you think there is a higher than expected representation in Capricorn?
  3. Is the proportion of accidents under Capricorn significantly greater than the other signs? (This can be tested with a test of equal p-values)
  4. What do you think of the astrologer's explanation of the results? Can you think of another explanation?


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