For people smarter than me, plz help!

A graduate student is comparing final-exam test scores of male and female students in an introductory physics class. She starts with no expectations as to which sex will score more highly. After seeing that men did better than women on the first quiz, she tests a one-sided alternative about the mean final-exam scores,

She finds z=1.9 with one-sided P- value is P=0.0272.

She should have used the

two-sided alternative hypothesis.

one-sided alternative hypothesis.

What is the correct P-value (0.0001) for z=1.9?

Question

For people smarter than me, plz help! 

A graduate student is comparing final-exam test scores of male and female students in an introductory physics class. She starts with no expectations as to which sex will score more highly. After seeing that men did better than women on the first quiz, she tests a one-sided alternative about the mean final-exam scores,



 
She finds z=1.9 with one-sided P- value is P=0.0272.

 

She should have used the

 
two-sided alternative hypothesis.
 
one-sided alternative hypothesis.
 

What is the correct P-value (0.0001) for z=1.9?

anonymous · Answer

p-value applicable to one tailed test = P(Z > z)
 = P(Z > 1.9)
 = 0.0287
 p-value applicable to two tailed test = 2*P(Z > z) 
 = 2*P(Z > 1.9)
 = 2*0.0287
 = 0.0574

 One sided alternative hypothesis is to be used
 Correct p-value for z = 1.9 is 0.0287

anonymous · Answer

so yes it would be the correct answer

goformit100 · Answer

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