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Statistics for Everyday Life

Probability and Prediction quiz

14 questions on Probability and Prediction, graded instantly with an explanation for every answer. Free and no sign-up — your best score is saved on this device. Want to study first? Read the Probability and Prediction lessons.

Probability and Prediction — Module Assessment

14 questions · pass mark 75%

  1. 1.You have made 50 forecasts you each marked '80% confident.' Which outcome shows you were well calibrated?
  2. 2.A colleague says a one-off product launch has a '75% chance' of succeeding. Which reading of probability is this?
  3. 3.A test is 99% accurate and a condition affects 1 in 1,000 people. You test positive. Roughly what is the chance you have the condition?
  4. 4.In the Monty Hall problem, after the host reveals a goat, why should you switch doors?
  5. 5.What does a probability distribution give you that a single average does not?
  6. 6.Why can assuming a normal distribution be dangerous for something like financial losses?
  7. 7.How is the expected value of an uncertain choice calculated?
  8. 8.Why can a bet with positive expected value still be a bad decision?
  9. 9.A roulette wheel lands on black eight times running. Why is red not more likely on the next spin?
  10. 10.Flight instructors found that cadets praised after a great manoeuvre usually did worse next time, and cadets criticized after a poor one usually improved. What best explains this?
  11. 11.A forecaster says "70% chance of rain" and the day stays dry. What does this tell us about the forecast?
  12. 12.According to Tetlock's forecasting research, what most distinguishes the best forecasters?
  13. 13.A screening test for a condition affecting 1 in 100 people catches 90% of real cases but gives a false positive for 9% of healthy people. You test positive. Roughly how likely are you to actually have the condition?
  14. 14.A wager has a slightly positive expected value but requires staking everything each round, with a real chance of losing almost all your savings. Why might it still be a bad decision?
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