Which of the following is NOT an observation about critical values? Choose the correct answer below. A. The number is a critical value that corresponds to an area of 1 to its left. B. The number is a critical value that is a z score with the property that it separates an area of in the right tail of the standard normal distribution. C. A critical value is the number on the borderline separating sample statistics that are likely to occur from those that are unlikely to occur. D. A critical value is the area in the right-tail region of the standard normal curve

The correct options are;

A. The number z_α/2 is a critical value that corresponds to an area of 1 − α/2 to its left.

B. The number z_α/2 is a critical value that is a z score with the property that

it separates an area of α/2 in the right tail of the standard normal distribution.

C. A critical value is the number on the borderline separating sample statistics that are likely to occur from those that are unlikely to occur.

D. A critical value is the area in the right-tail region of the standard normal curve.

Option D: A critical value is the area in the right - tail region of the standard normal curve.

Step-by-step explanation:

A critical value is defined as the line on a graph that makes that graph split into sections.

Now, either one or two of the sections split will fall into the “rejection region“.

So, if the test value falls into the rejection region, it means we will reject the null hypothesis.

Looking at the options given, options A, B & C are possible observations that we could deduce about critical values based on the definition given above.

Option D is not an observation because the critical value is what denotes the z-score with an area of alpha in the right tail region