TED-ED: Can you solve the false positive riddle? - Alex Gendler

The video tutorial explores a scenario involving a rare mineral, unobtainium, and a detector used by Tricky Joe. Despite the detector's high accuracy, the rarity of unobtainium leads to a high chance of false positives. This is explained through the base rate fallacy and conditional probability. The tutorial highlights the importance of understanding these concepts to make informed decisions, illustrating the broader implications of false positives in fields like medical testing and surveillance.

What is the main reason Tricky Joe's offer seems appealing at first?

• The detector is known to be highly reliable.

• The rock is visibly different from others.

• Joe is offering a very low price for the rock.

• Unobtainium is very common in the mine.

How many rocks in the mine are expected to contain unobtainium?

• 100

• 10

• 50

• 1

What is the probability that a rock triggering the detector actually contains unobtainium?

• 50%

• 1%

• 9%

• 90%

What is the base rate fallacy in the context of this scenario?

• Ignoring the rarity of unobtainium when considering the detector's accuracy.

• Assuming the detector is always wrong.

• Believing unobtainium is more common than it is.

• Thinking the detector's error rate is zero.

Why can false positives in medical testing be problematic?

• They are preferred over true positives.

• They are more accurate than false negatives.

• They can cause unnecessary stress or treatment.

• They always lead to correct diagnoses.