Chapter 7 Quiz Review

As sample size increases, the value of the standard error also increases.

• True

• False

Answer explanation

False, Standard error decreases as n increases.

Under what circumstances will the distribution of sample means be a normal-shaped distribution?

• If the sample size is relatively large (n = 30).

• If the sample size is relatively small (n = 10).

• If the population scores are positively skewed.

• If the distribution only works with population parameters.

Answer explanation

In order to approach a normal-shaped distribution with sample means, the larger the sample size (n), the more probable it is that the sample mean will be close to the population mean.

A population has μ = 80 and σ = 12. Find the z-score corresponding to the sample mean M = 84 for a sample of n = 9 scores.

• z = +1.00

• z = -1.00

• z = -1.50

• z = +2.00

Tags

CCSS.HSS.ID.A.4

The magnitude of the standard error can be larger than the population standard deviation.

• True

• False

Answer explanation

False. The standard error is always less than or equal to the standard deviation. The two values are equal only when n = 1.

A researcher plans to select a random sample of n = 36 individuals from a population with a standard deviation of σ = 18. On average, how much error should the researcher expect between the sample mean and the population mean?

A population forms a normal distribution with a mean of μ = 50 and a standard deviation σ = 10. A sample of n = 4 scores from this population has a mean of M = 55. Would you describe this as relatively typical?

• Yes, z = -1.00

• Yes, z = 1.00

• No, z = 2.68

• No, z = 1.25

Tags

CCSS.HSS.ID.A.4

The ____ is the standard deviation of the distribution of sample means.

• Distribution of Sample Means

• Expected Value of M

• Standard Error of M

• Sample Mean

We expect the MEAN of the distribution of sample means to be ____.

• Equal to the population mean

• Slightly different from the population mean

• Higher than the population mean

• One standard deviation below the population mean

Answer explanation

In the Module 5.1 Lecture video at 10:58, Dr. Story states that we expect the mean of the distribution of sample means to be equal to the population mean.