Copy of A medical researcher gives a new muscle relaxant to

Copy of A medical researcher gives a new muscle relaxant to 200 patients

and determines that 156 have beneficial results. The muscle relaxants

currently in use have a success rate of .70. Test whether the new drug

is superior to the existing drugs.

i) Choose the null hypothesis, by recording the letter of your choice from below

a) H₀: p? = .78

b) H₀: p = .70

c) H₀: p > .78

d) H₀: p > .70

ii) Choose the alternative hypothesis, by recording the letter of your choice from below

a) H_a: p? = .78

b) H_a: p > .78

c) H_a: p? > .70

d) H_a: p > .70

iii) What is the value of the test statistic? Give your answer to two digits past the decimal.

iv) What is the P value or significance probability? Give your answer to 3 places past the decimal, without a leading zero.

v) Choose the appropriate conclusion.

a) no evidence against the null hypothesis

b) weak evidence against the null hypothesis

c) strong evidence against the null hypothesis

d) very strong evidence against the null hypothesis

(i) b) H₀: p = .70

---------------------------------------------------------------------------------------------------
(ii)d) H_a: p > .70

---------------------------------------------------------------------------------------------------

(iii)test statistic:

Z=(phat-p)/sqrt(p*(1-p)/n)

=(156/200-0.7)/sqrt(0.7*0.3/200)

=2.47

---------------------------------------------------------------------------------------------------

(i.v) It is a right-tailed test.

So the p-value= P(Z>2.47) = 0.007 (from standard normal table)

---------------------------------------------------------------------------------------------------

(V) c) strong evidence against the null hypothesis