When would you use a one-tailed rather than a two-tailed t-test ...

[javeds]

When would you use a one-tailed rather than a two-tailed t-test when checking significance levels?
 
  What will be an ideal response?

Question 2

Which of the following measures are government regulations to increase competition?
 
  A) Government ends the ban on steel imports.
  B) Government shortens the term of the patent for a drug.
  C) Government subsidizes firms to enter energy market.
  D) All of above.

[sabina576]

Answer to Question 1

You would use a one-tailed test when the sign of the variable is important. That is, if you only want to know if the independent variable has a statistically significant effect on the dependent variable, a two-tailed test should be used. If direction of effect is important, then a one-tailed test should be used.

Answer to Question 2

D