1) A noted psychic was tested for ESP. The psychic was presented
with 180 cards face down and was asked to determine if the card was
one of 5 symbols: a star, cross, circle, square, or three wavy
lines. The psychic was correct in 43 cases. Let p represent the
probability that the psychic correctly identifies the symbol on the
card in a random trial. Assume the 180 trials can be treated as an
SRS from the population of all guesses.
To see if there is evidence that the psychic is doing better than
just guessing, we test
H0:p=.2
??:?>.2
(a) What is the z-statistic for this test?
(b) What is the P-value of the test?
2) An Office of Admission document at a certain university claims that 56.1% of their undergraduates are female. To test this claim, a random sample of 230 undergraduates was selected. In this sample, 58.1% were female. Is there sufficient evidence to conclude that the document's claim is false? Carry out a hypothesis test at a 10% significance level.
A. The value of the test statistic is:
B. The p-value is
D. Your decision for the hypothesis test:
A. Reject H0.
B. Do Not Reject H0.
C. Reject H1.
D. Do Not Reject H1.
1)
Given :
(a) z-test statistic formula is
Therefore the z-statistic for this test is 1.30
(b)
p-value :
As the alternative hypothesis (Ha) is greater than (>) type , this is right tailed test .
So p-value = P(Z>z)
= 1 - P(Z<z)
Using Excel function , =NORMSDIST (z)
=NORMSDIST(1.30)
=.9032
P-value = 1 - .9032 = .0968
P-value = .0968
Therefore the P-value of the test is .0968
Get Answers For Free
Most questions answered within 1 hours.