Wednesday, May 23, 2012

selection bias - cosmo CSI

during the 1960's, criminal investigators were puzzled by an observation that in many countries with a seaside a considerable number of dismembered feet in sports sneakers were washed ashore. a logical explanation seemed to be a serial killer murdering joggers, but the truth is different and involves statistics, and the biasedness of observations: what would be your guess?


  1. Try 2 - Just a guess, but the feet are from people who had died (and decayed) at sea. The lighter sports sneakers float whereas heavier footware sink, and uncovered feet get eaten. The selection bias leave you with just feet in sports sneakers, even tho the overall population was initially a range of feet and shoes.

  2. well, cusp is too good for cosmologyquestionoftheweek.... but let me add a bonus question here! can you think of a similar situation in cosmology?