Why is it preferable to choose a one-sided alternative rather ...

[clmills979]

Why is it preferable to choose a one-sided alternative rather than a two-sided alternative in the situation where you are only interested in results that are extreme in one direction?
 a. Your p-value would be half as much as it would be for a two-sided test (assuming the test statistic is the same each time, and is in the direction of the one-sided alternative you selected.)
  b. Your results don't have to be as extreme in order to achieve statistical significance.
  c. Your conclusions can be more informative because they will have a direction associated with them.
  d. All of the above.

Question 2

Suppose your test statistic for a two-sided test for the difference in two means resulted in a standard score of 0 . What would the resulting p-value be?
 a. 0
  b. .5
  c. 1
  d. Not enough information to tell.

[whitcassie]

Answer to Question 1

D

Answer to Question 2

C

[clmills979]

TYSM

[nguyenhoanhat]

Gracias!