6. In January 2002, two students made worldwide headlines byspinning a Belgian e

Question

6. In January 2002, two students made worldwide headlines byspinning a Belgian euro 250 times and getting 140 heads - that's56%. That makes the 90% confidence interval (51%, 61%). What doesthis mean? Are these conclusions correct? Explain.

a) Between 51% and 61% of all euros are unfair.
b) We are 90% sure that in this experiment this euro landed headson between 51% and 61% of the spins.
c) We are 90% sure that spun euros will land heads between 51% and61% of the time.
d) If you spin a euro many times, you can be 90% sure of gettingbetween 51% and 61% heads.
e) 90% of all spun euros will land heads between 51% and 61% of thetime.

Explanation / Answer

FALSE - This experiment says nothing about howmany Euros are fair or not. What it does say is that they are90% sure (not 100% sure, there is always uncertainty) that they areunfair (defined as being not 50%heads/tails)
b) We are 90% sure that in this experiment this euro landed headson between 51% and 61% of the spins. FALSE - We are 100% sure that in this experimentthe euro landed on heads 56% of the time - what we are uncertainabout is what would happen if you flipped it infinitetimes
c) We are 90% sure that spun euros will land heads between 51% and61% of the time. TRUE -This is what the experiment tells us - how likely a euro is to landheads (at least we are 90% sure of it)
d) If you spin a euro many times, you can be 90% sure of gettingbetween 51% and 61% heads. TRUE -although deceptively worded, this is saying the same thing as(c)
e) 90% of all spun euros will land heads between 51% and 61% of thetime. FALSE - Wrong - this is just wrongin every way possible and just doesn't make sense
Hope thathelps

Related Questions

Navigate

• Browse (All)
• Browse 6
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.