Research Question:

Does the use of a new surgical instrument decrease the average time it takes to perform a laparoscopic cholecystectomy?

Null Hypothesis:

There is no difference in the average time it takes to perform a laparoscopic cholecystectomy with the new surgical instrument compared to the standard instrument.

Alternative Hypothesis:

The average time it takes to perform a laparoscopic cholecystectomy with the new surgical instrument is significantly lower than with the standard instrument.

Type 1 Error:

Rejecting the null hypothesis when it is true would be a Type 1 error in this scenario. This would mean concluding that the new surgical instrument decreases the average time it takes to perform the surgery when it actually does not.

Type 2 Error:

Failing to reject the null hypothesis when it is false would be a Type 2 error. This would mean failing to conclude that the new surgical instrument decreases the average time it takes to perform the surgery when it actually does.

I believe this is a one-tailed test as the research question, it specifically asks if the new surgical instrument decreases the average time it takes to perform the surgery, indicating a directional hypothesis. respose with reference