Idea 19of 22Builds onMore trials settle closer
A big gap after many trials
What if a big experiment lands far from the theory?
Today you'll discover
- how far 1000 fair spins usually land
- what a big gap means
- how an experiment tests a spinner
Think firstThis spinner should be 1/4 orange
This spinner should be 1/4 orange. 1000 spins gave 498 orange. What does that suggest?
Decide first, then press Next. Compare the 1000-spin bar with the dashed line.
Rows of results for a spinner that should be 1/4 orange: runs of 10 at 5, 6 and 4, then 52 of 100 and 498 of 1000, all near the middle of the scale while the dashed theory line stands at 1/4. A sentence reads 498 of 1000, expected about 250: far off. For comparison, a fair spinner's 1000 spins land at 246. The last step shows a coin with 700 heads in 1000 flips.
See the whole ideathe big idea and the key word, in one place
The big idea
A big gap after many trials means the spinner is probably biased, not just unlucky.
Compare themA gap in 10 spins is chance. The same gap in 1000 spins is a clue: the spinner may be bent or wrongly drawn.
Easy to get wrongOne short run never proves a spinner is unfair. Only a big experiment can.
Key word
- biased
- not fair: one outcome comes up more often than it should
Ready to use it?
- Decide whether a large experiment shows an unfair spinner or coin.