Peter Donnelly: How juries are fooled by statistics

The speaker discusses the challenges and misconceptions surrounding statistics, using humor and real-world examples. They explore probability through coin tosses, link genetics with probability, and examine the accuracy of disease testing. A case study on Sally Clark highlights statistical errors in the legal system. The talk concludes with a call to improve understanding of statistics in everyday life.

What is the speaker's main challenge in making statistics interesting?

• Statistics lacks the excitement of other scientific topics.

• Statistics is too complex for most people.

• Statistics is not applicable to everyday life.

• Statistics is only for mathematicians.

In the coin toss example, which pattern takes longer to appear on average?

• Head-Head-Tail

• Head-Tail-Tail

• Head-Tail-Head

• Tail-Head-Tail

Why does the pattern Head-Tail-Head take longer to appear than Head-Tail-Tail?

• It overlaps itself.

• It is less likely to occur.

• It requires more tosses.

• It is a more complex pattern.

How is the concept of probability related to genetics?

• Both involve random processes.

• Both use mathematical models.

• Both deal with sequences of events.

• Both require statistical analysis.

What is the main goal of the International HapMap project?

• To understand genetic differences between people.

• To find a cure for genetic diseases.

• To map the entire human genome.

• To sequence DNA of different species.

What factor significantly affects the accuracy of a medical test result?

• The test's sensitivity.

• The cost of the test.

• The test's specificity.

• The prevalence of the disease.

In the medical test example, what is the probability of having the disease if the test is positive?

• 100%

• Less than 1%

• 99%

• 50%

What was the main statistical error in the Sally Clark case?

• Faulty test equipment.

• Incorrect data collection.

• Misinterpretation of probability.

• Biased jury selection.

Why is it important to understand statistics in legal contexts?

• To ensure fair trials.

• All of the above.

• To prevent wrongful convictions.

• To interpret evidence correctly.

What is a common issue people face when reasoning with uncertainty?

• Misunderstanding probabilities.

• Ignoring statistical evidence.

• Overconfidence in predictions.

• All of the above.