How to determine test a one side or two side test

Hi Shaikh!

Thanks for reaching out.

The decision between a one-sided and a two-sided test stems from the specific question you are seeking to answer. If the question is about checking for a difference in any direction (greater or lesser), a two-sided test is appropriate. If the question is specifically about whether a parameter is greater than or less than a certain value, but not both, then a one-sided test is used.

The choice between a one-sided and a two-sided test should be driven by the specific hypothesis or research question you are investigating

Hope this helps.

Best,

Ivan