What is a critical value for a left-tailed z-test with a significance level of 5%?
Question 37 options:
-2.447
1.65
-1.65
-2.33
1.28
The correct answer is -1.65.
In a left-tailed test, the critical value is the z-score that corresponds to the given significance level.
At a significance level of 5%, the area in the left tail is 5%. This means that the remaining area in the right tail is 100% - 5% = 95%.
From the standard normal distribution table, we find the z-score that corresponds to an area of 95% in the right tail, which is approximately 1.65.
However, since this is a left-tailed test, we need to use the negative of this value as the critical value. Therefore, the critical value for a left-tailed z-test with a significance level of 5% is -1.65.