 # Review Questions

1. As you increase the sample size of a random sample, the standard error of the mean:

#### increases.

This answer is incorrect! The sample size affects the accuracy and the standard error of the mean. How so?

You are correct!

#### remains the same.

This answer is incorrect! The sample size affects the accuracy and the standard error of the mean. How so?

#### cannot be determined from the above information.

This answer is incorrect! The sample size affects the accuracy and the standard error of the mean. How so?

2. As you increase the sample size of a random sample, the sample mean:

You are correct!

#### becomes less accurate.

This answer is incorrect! The sample size affects the sample mean. How so?

#### remains the same.

This answer is incorrect! The sample size affects the sample mean. How so?

3. As you increase the sample size for a random sample, the shape of the sampling distribution of the mean:

#### becomes more wide and flat.

This answer is incorrect! According to the Central Limit Theorem, the sample size affects the sampling distribution of the mean. How so?

#### becomes more skewed.

This answer is incorrect! According to the Central Limit Theorem, the sample size affects the sampling distribution of the mean. How so?

#### remains the same.

This answer is incorrect! According to the Central Limit Theorem, the sample size affects the sampling distribution of the mean. How so?

#### approaches normal.

You are correct!

4. True or False? The standard deviation of a sampling distribution of means is smaller than the standard deviation of the population when the sample size is 2.

#### True.

You are correct! The standard error of the mean is always smaller than the standard deviation of the population when the sample size is 2 or greater.

#### False.

This answer is incorrect! How is the standard deviation of the sampling distribution calculated?

5. Imagine we measured the height of all the male students at a particular college. We found that the average height of men at this school was 70 inches (5’10”) with a standard deviation of 2 inches and the distribution is approximately normal in shape. If we were to randomly select one male student from this college, what is the probability that this student is 73 inches (6’1″) or taller?

#### <0.001.

This answer is incorrect! What is the z score of 73 inches and corresponding right-tailed p value?

You are correct!

#### 0.154.

This answer is incorrect! What is the z score of 73 inches and corresponding right-tailed p value?

6. Still think about the same college in the previous question. Imagine we selected 16 male students at random. What is the probability that the average height of these 16 male students is 73 inches or taller?

You are correct!

#### 0.067.

This answer is incorrect! The standard error of the mean depends upon the sample size.

#### 0.154.

This answer is incorrect! The standard error of the mean depends upon the sample size.

7. Imagine that you took a sample of male students from the college in the prior questions and found a mean height of 68 inches. For which of the sample sizes below would you find this most surprising.

#### N = 10.

This answer is incorrect! For which sample size would it be most unlikely to obtain a sample mean that is one standard deviation below the population mean?

#### N = 50.

This answer is incorrect! For which sample size would it be most unlikely to obtain a sample mean that is one standard deviation below the population mean?

You are correct!

#### N does not matter.

This answer is incorrect! For which sample size would it be most unlikely to obtain a sample mean that is one standard deviation below the population mean? 