1st drop down Reject or do not reject 2nd drop down Is evide

Solution

a)

Ho: pi1<= pi2
Ha: pi1 > pi2 [ANSWER, OPTION D]

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B)

Formulating the hypotheses          

Ho: p1^ - p2^   <=   0  
Ha: p1^ - p2^   >   0  

Here, we see that pdo =    0   , the
hypothesized population proportion difference.  
          
Getting p1^ and p2^,          
          
p1^ = x1/n1 =    0.34      
p2 = x2/n2 =    0.2      
          
Also, the standard error of the difference is          
          
sd = sqrt[ p1 (1 - p1) / n1 + p2 (1 - p2) / n2] =    0.062      
          
Thus,          
          
z = [p1 - p2 - pdo]/sd =    2.258064516 = 2.258   [ANSWER, PART B]  

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As significance level =    0.05   , then the critical z is  
          
zcrit =    1.644853627      

Thus, the rejection region is ZSTAT > 1.645 [ANSWER, OPTION ]

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Thus comparing z > zcrit, WE REJECT THE NULL HYPOTHESIS.

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c)

Yes, the result in b) makes it appropriate to claim it.