14 Gender Selection The Genetics IVF Institute conducted a

14.

Gender Selection The Genetics & IVF Institute conducted a clinical trial of the YSORT method designed to increase the probability of conceiving a boy. As of this writing, 291 babies were born to parents using the YSORT method, and 239 of them were boys. Use a 0.01 significance level to test the claim that the YSORT method is effective in increasing the likelihood that a baby will be a boy.

Solution

Formulating the null and alternatuve hypotheses,          
          
Ho:   p   <=   0.5
Ha:   p   >   0.5
As we see, the hypothesized po =   0.5      
Getting the point estimate of p, p^,          
          
p^ = x / n =    0.821305842      
          
Getting the standard error of p^, sp,          
          
sp = sqrt[po (1 - po)/n] =    0.029310519      
          
Getting the z statistic,          
          
z = (p^ - po)/sp =    10.96213414      
          
As this is a    1   tailed test, then, getting the p value,  
          
p =    2.90563*10^-28      
significance level =    0.01      

Comparing p < 0.01, we   REJECT THE NULL HYPOTHESIS.  

Thus, there is significant evidence that the YSORT method is effective in increasing the likelihood that a baby will be a boy. [CONCLUSION]