# Major issues with binomial model. HELP!

• Mar 27th 2009, 09:07 PM
NumbersNumbersNumbers
Major issues with binomial model. HELP!
How the heck do I enter the following (red highlighted) into a calculator to figure it out?

http://img15.imageshack.us/img15/443...pture24.th.png

Basically the problem(s) I'm trying to figure out are:

1) A basketball player tell his coach that he raised his foul-shot profiency from 45% to 65%. Dubious, the coach asks him to take 10 shots, and is surprised when the player makes 9 out of 10.

Suppose the player is really no better than before - still a 45% shooter. Whats the probability that he could hit 9 out of 10 shots anyways?

If the player really can hit 65% now, and it takes at least 9 out of 10 succesful shots to convice the coach, whats the power of the test?
• Mar 27th 2009, 11:21 PM
Bilbo Baggins
Quote:

Originally Posted by NumbersNumbersNumbers
How the heck do I enter the following (red highlighted) into a calculator to figure it out?

http://img15.imageshack.us/img15/443...pture24.th.png

Basically the problem(s) I'm trying to figure out are:

1) A basketball player tell his coach that he raised his foul-shot profiency from 45% to 65%. Dubious, the coach asks him to take 10 shots, and is surprised when the player makes 9 out of 10.

Suppose the player is really no better than before - still a 45% shooter. Whats the probability that he could hit 9 out of 10 shots anyways? No such word

If the player really can hit 65% now, and it takes at least 9 out of 10 succesful shots to convice the coach, whats the power of the test?

If the player has a .45 probability of hitting any given free throw and he makes 9 out of ten then the probability of that outcome is given by the binomial probability function and is simply (10 choose 9)*.45^9*.55
Regarding the power of the test, if the coach where testing a null hypothesis, it would be far more likely that a .65 free thrower lands 9 out of ten than a .45 thrower.