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Probability Presentation

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Probability Presentation

  1. 1. THE BODY IN THE BAG<br />Presenters: <br />Dina Gaughan, Megan Poole, & <br />Amy Shuleski<br />February 24, 2010<br />MBA 512<br />
  2. 2. Man Finds large canvas bag floating in river<br />Preliminary investigation reveals body<br />Sex/Race/Age Unknown<br />Body in the Bag<br />
  3. 3. Victim and Offender – Adults over 18yrs of age<br />Victim/Offender Relationships<br />2003 Uniform Crime Reports – FBI<br />http://www.fbi.gov/ucr/03cius.htm<br />Analysis Profiles<br />Victim<br />Offender<br />Joint<br />Waiting on Forensics Analysis<br />Identify Preliminary Profile<br />
  4. 4.
  5. 5.
  6. 6. <ul><li>Classical Method
  7. 7. P (E) = Number of ways that E can occur</li></ul> Number of possible outcomes<br /><ul><li>Addition Rule
  8. 8. P (A or B) = P (A) + P (B)
  9. 9. Multiplication Rule
  10. 10. P (A&B) = P (A) * P (B)</li></ul>Probability Formulas<br />
  11. 11. (Classical Method)<br />Race:<br />White: 3,562 / 6,911 51.5%<br />Black: 3,098 / 6,911 44.8%<br />Other: 195 / 6,911 2.8%<br />Unknown: 56 / 6,911 .8%<br />Sex:<br />Male: 4,987 / 7,024 71% <br />Female: 1,962 / 7,024 27.9%<br />Unknown: 75 / 7,024 1.1%<br />Victim Profile Prediction<br />
  12. 12. (Addition Rule)<br />White or Black<br />=(3562/6911) + (3098/6911) = 96.4%<br />Male or Female<br />=(4987/7024) + (1962/7024) = 98.9%<br />Victim Profile Prediction<br />
  13. 13. (Multiplication Rule)<br />White & Male<br />=(3562/6911) * (4987/7024) = 36.6%<br />White & Female<br />=(3098/6911) * (1962/7024) = 14.4%<br />Black & Male<br /> =(3098/6911) * (4987/7024) = 31.8%<br />Black & Female<br /> =(3098/6911) * (1962/7024) = 12.5%<br />Victim Profile Prediction<br />
  14. 14. Victim Profile Prediction<br />
  15. 15. (Classical Method)<br />Race:<br />White: 3,323 / 6,911 48.1%<br />Black: 3,412 / 6,911 49.4%<br />Other: 176 / 6,911 2.5%<br />Unknown: 56 / 6,911 0.8%<br />Sex:<br />Male: 6,220 / 7,024 88.6%<br />Female: 691 / 7,024 9.8%<br />Unknown: 113 / 7,024 1.6%<br />Offender Profile Prediction<br />
  16. 16. (Addition Rule)<br />White or Black<br />=(3323/6911) + (3412/6911) = 97.5%<br />Male or Female<br />=(6220/7024) + (691/7024) = 98.4%<br />Offender Profile Prediction<br />
  17. 17. (Multiplication Rule)<br />White & Male<br />= (3323/6911) * (6220/7024) = 42.6%<br />White & Female<br />=(3323/6911) * (691/7024) = 4.7 %<br />Black & Male<br />=(3412/6911) * ( 6220/7024) = 43.7%<br />Black & Female<br />=(3412/6911) * (691/7024) = 4.9%<br />Offender Profile Prediction<br />
  18. 18. Offender Profile Prediction<br />
  19. 19. (Multiplication Rule)<br /><ul><li>Likelihood of Victim & Offender same race:
  20. 20. White: .515 x .481 24.8%
  21. 21. Black: .448 x .494 22.1%
  22. 22. Other: .028 x .025 .1%
  23. 23. Likelihood of Victim & Offender same sex:
  24. 24. Male: .71 x .88 62.9%
  25. 25. Female: .279 x .098 2.7%
  26. 26. Unknown: .011 x .016 .02%</li></ul>Joint Profile Prediction<br />
  27. 27. Victim<br />White & Male - 36.6%<br />Offender<br />Black & Male - 43.7%<br />Joint – Both are<br /><ul><li>White: 24.8% (Disagrees with above Prediction)
  28. 28. Male: 62.9% (Agrees with above prediction)</li></ul>Profile Predictions <br />
  29. 29. No Identification<br />Autopsy<br />In water for 2 weeks<br />Forensics Information Recovered<br />White Female<br />Blonde Hair<br />Mid 30’s<br />No children<br />No jewelry<br />Forensics Analysis - Victim<br />
  30. 30. Victim Profile Probability did not match the Forensic Analysis<br />Analysis Determined<br />White Female<br />Probabilities<br />White Male – 36.6 % <br />White & Female - 14.4%<br />Forensics Analysis - Victim<br />
  31. 31. Based on Victim’s Race – Likelihood Offender is:<br />White<br />3,017/3,562 = 84.7 %<br />Black<br />501/3,562 = 14.1 %<br />Other<br />44/3,562 = 1.7 %<br />Offender Profile Posting<br />
  32. 32. Based on Victim’s Sex– Likelihood Offender is:<br />Male<br />1754/1962 = 89.4 %<br />Female<br />185/1962 = 9.4 %<br />Unknown<br />231/1962 = 1.2 %<br />Offender Profile Posting<br />
  33. 33. (Multiplication Rule)<br />White and Male<br />.847 * .894 = 75.7 %<br />Probability that the Offender is<br />White and Male is 75.7 %<br />Official Offender Profile Posting<br />
  34. 34. Have you seen this man?If so, dial 911<br />White Male<br />Questions?<br />

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