List

Probability - it's deadly serious!

An understanding of probability is important in medicine, law and wider society. These problems invite students to consider some scenarios where interpreting probabilities incorrectly can have serious consequences.
Introductory Video
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Introductory video

An introductory video to the Probability and Evidence collection
Spots and Measles
problem

Spots and measles

Age
11 to 16
Challenge level
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99% of people who have measles have spots. Ben has spots. Do you think he has measles?
Do Rare Events Happen?
problem

Do rare events happen?

Age
11 to 16
Challenge level
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I'd be very surprised if I had three children all with the same birthday, but I read in the paper that it happened to one family...
The ELISA Test
problem

The ELISA test

Age
14 to 18
Challenge level
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In 1% of cases, an HIV test gives a positive result for someone who is HIV negative. How likely is it that someone who tests positive has HIV?

Matching Criminals
problem

Matching criminals

Age
14 to 18
Challenge level
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DNA profiling is an invaluable tool for the police. However, when it comes to probability, things aren't always as straightforward as they seem.