Q2 A recent USA TODAYCNNGallup Poll showed that most America

Q2.

A recent USA TODAY/CNN/Gallup Poll showed that most American people support Bush’s effort in the Middle East peace process. The poll of 2000 adults was conducted and 1243 people said they supported Bush’s efforts. It is believed that 60% of American people supported Bush’s efforts. If we are to conduct a hypothesis test that more than 60% supported Bush’s efforts,

Perform a hypothesis test at a 5% significance level to prove whether or not if more than 60% of the American people really supported Bush’s efforts by doing all the steps I show you in class.

Note: “You can use either the Critical value approach or the p-value approach.” (20 pts)

Solution

Formulating the null and alternatuve hypotheses,          
          
Ho:   p   <=   0.6
Ha:   p   >   0.6
As we see, the hypothesized po =   0.6      
Getting the point estimate of p, p^,          
          
p^ = x / n =    0.6215      
          
Getting the standard error of p^, sp,          
          
sp = sqrt[po (1 - po)/n] =    0.010954451      
          
Getting the z statistic,          
          
z = (p^ - po)/sp =    1.962672498      
          
As this is a    1   tailed test, then, getting the p value,  
          
p =    0.02484212      

significance level =    0.05      

As P < 0.05, we REJECT THE NULL HYPOTHESIS.      

Thus, there is significant evidence that more than 60% supported Bush’s efforts. [CONCLUSION]