Stats: Correct or not?
Can someone check my work?
1. A recent study found that, at most, 32% of people who have been in a plane crash have died. In a sample of 100 people who were in a plane crash, 38 died. Is the study statement believable?
H(null): P= 0.32
H(alternative): P>0.32 Right tailed
Then you use the test statistic
z= 0.38-0.32/sqrt(0.32 x 0.68/100)~ 1.29
So I look for the area on the z score chart and it should be 0.90147. However since that's the area on the left side of the z score. So i must do 1-0.90147= .0985
.0985<0.05 so Reject H(null).....So the statement is believable right?
What alpha level are you using?. You didn't say. I assumed .05
Test stat = 1.2862
critical value = 1.6449
p value = 0.0992
Do not reject the null hypothesis.
There is not enough evidence at the 5% level to reject the claim that at most 32% of plane crash victims die.
The claim is valid.
If you test at alpha = 0.1, then you can reject.
Assuming your arithmetic is right wha you have is:
Originally Posted by Nimmy
0.0985>0.05 so we do not reject H(null) at the .....So the statement is believable in that we do not reject the hypothesis at this level.
Is that another way you can solve it? Is my work wrong? How did you get the critical value?
Originally Posted by galactus
oh lol you right. I assume it was 0.5 instead of 0.05
Originally Posted by CaptainBlack