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Do Left-handed People Really Die Young?

Use pandas and Bayesian statistics to see if left-handed people actually die earlier than righties.

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  • 10 tasks
  • 2,152 participants
  • 1,500 XP

Project Description

Barack Obama is left-handed. So are Bill Gates and Oprah Winfrey; so were Babe Ruth and Marie Curie. A 1991 study reported that left-handed people die on average nine years earlier than right-handed people. Nine years! Could this really be true?

In this project, you will explore this phenomenon using age distribution data to see if we can reproduce a difference in average age at death purely from the changing rates of left-handedness over time, refuting the claim of early death for left-handers. This notebook uses pandas and Bayesian statistics to analyze the probability of being a certain age at death given that you are reported as left-handed or right-handed.

Project Tasks

  • 1Where are the old left-handed people?
  • 2Rates of left-handedness over time
  • 3Applying Bayes' rule
  • 4When do people normally die?
  • 5The overall probability of left-handedness
  • 6Putting it all together: dying while left-handed (i)
  • 7Putting it all together: dying while left-handed (ii)
  • 8Plotting the distributions of conditional probabilities
  • 9Moment of truth: age of left and right-handers at death
  • 10Final comments
Madeleine Bonsma-Fisher

PhD Candidate at University of Toronto

Madeleine Bonsma-Fisher is a graduate student in the Department of Physics at the University of Toronto, where she uses coding and mathematical models to study the CRISPR bacterial adaptive immune system. She is an executive member of UofT Coders, a campus group dedicated to peer-led learning in a variety of programming and data science topics. Madeleine loves Python but thinks R is pretty neat too.

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  • Python LogoPython
  • Topics

    Data ManipulationData VisualizationProbability & StatisticsImporting & Cleaning Data