Question

a researcher conducts a hypothesis test to evaluate the effect of the treatment. the hypothesis test produces a z-score of z= 2.75. Assuming that the researcher is using a two-tailed test,what decision should be made?

Answer #1

solution:

this is the two tailed test .

Test statistic = z=2.75

P(z >2.75 ) = 1 - P(z < 2.75 ) = 1-0.9970=0.0030 using z table

P-value = 2*0.0030=0.0060

if

= 0.08

P-value <

Reject the null hypothesis .

if

= 0.05

P-value >

fail to Reject the null hypothesis .

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Question #3
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