Question 1

A sample of n = 4 scores is selected from a population with μ = 40 with σ = 8,and the sample mean is M = 43.What is the expected value for the sample mean?

Accepted Answer

A) 40 
B) 10 
C) 8 
D) 2

Question 2

Samples of size n = 9 are selected from a population with μ = 80 with σ = 18.What is the expected value for the distribution of sample means?

Accepted Answer

A) 6 
B) 18 
C) 80/3 
D) 80

Question 3

A sample is selected from a population with µ = 30 and σ = 10.If the sample mean of M = 34 corresponds to z = +2.00,then the sample size is n = 25.

Accepted Answer

A) True 
 B)False

Question 4

In order for the distribution of sample means to be normal,it must be based on samples of at least n = 30 scores.

Accepted Answer

A) True 
 B)False

Question 5

A sample of n = 4 scores is selected from a population with μ = 50 and σ = 12.If the sample mean is M = 56,what is the z-score for this sample mean?

Accepted Answer

A) 0.50 
B) 1.00 
C) 2.00 
D) 4.00

Question 6

On average,a sample of n = 16 scores will provide a better estimate of the population mean than you would get with a sample of n = 9 scores from the same population.

Accepted Answer

A) True 
 B)False

Question 7

Find the z-score for the sample mean for each of the following samples obtained from a population with µ = 50 and σ = 12.
A)M = 56 for a sample of n = 4
B)M = 42 for a sample of n = 9
C)M = 51 for a sample of n = 36

Accepted Answer

The answer of Find the z-score for the sample mean...

Question 8

A sample of n = 4 scores is obtained from a population with μ = 70 and σ = 8.If the sample mean corresponds to a z-score of 2.00,what is the value of the sample mean?

Accepted Answer

A) M = 86 
B) M = 78 
C) M = 74 
D) M = 72

Question 9

A sample of n = 25 scores is selected from a population with μ = 70 and σ = 20.It is very unlikely that the sample mean will be greater than 72.

Accepted Answer

A) True 
 B)False

Question 10

Which combination of factors will produce the largest value for the standard error?

Accepted Answer

A) A large sample and a large standard deviation 
B) A small sample and a large standard deviation 
C) A large sample and a small standard deviation 
D) A small sample and a small standard deviation

Question 11

A sample of n = 4 scores is selected from a normal population with a mean of µ = 50 and a standard deviation of σ = 20.What is the probability of obtaining a sample mean greater than M = 48?

Accepted Answer

A) p = 0.6554 
B) p = 0.3446 
C) p = 0.5793 
D) p = 0.4207

Question 12

A sample of n = 25 scores is selected from a population with a mean of µ = 80 and a standard deviation of σ = 20.The standard error for the sample mean is 20.

Accepted Answer

A) True 
 B)False

Question 13

For a population with µ = 80 and σ = 20,the distribution of sample means based on n = 16 will have an expected value of ____ and a standard error of ____.

Accepted Answer

A) 5; 80 
B) 80; 5 
C) 20; 20 
D) 80; 1.25

Question 14

A sample of n = 9 scores is randomly selected from a population with µ = 80 and ? = 9.If the sample mean is M = 83,then the corresponding z-score is z = +3.00.

Accepted Answer

A) True 
 B)False

Question 15

If random samples,each with n = 9 scores,are selected from a normal population with µ = 80 and σ = 18,how much difference,on average,should there be between a sample mean and the population mean?

Accepted Answer

A) 2 points 
B) 3 points 
C) 6 points 
D) 18 points

Question 16

A sample of n = 36 scores is selected from a population with σ = 12.If the sample mean of M = 56 produces a z-score of z = +3.00,then what is the population mean?

Accepted Answer

A) 50 
B) 52 
C) 54 
D) 56

Question 17

If the sample size is equal to the population variance (n = σ²),then the standard error is equal to 1.

Accepted Answer

A) True 
 B)False

Question 18

If a sample of n = 4 scores is obtained from a population with μ = 70 and σ = 12,what is the z-score corresponding to a sample mean of M = 73?

Accepted Answer

A) z = 0.25 
B) z = 0.50 
C) z = 1.00 
D) z = 2.00

Question 19

A sample obtained from a population with σ = 12 has a standard error of 2 points.How many scores are in the sample?

Accepted Answer

A) n = 36 
B) n = 24 
C) n = 6 
D) n = 3

Question 20

For a normal population with µ = 40 and σ = 10,which of the following samples has the highest probability of being obtained?

Accepted Answer

A) M ≤38 for a sample of n = 4 
B) M≤ 36 for a sample of n = 4 
C) M ≤38 for a sample of n = 100 
D) M 36 for a sample of n = 100

Exam 7: Probability and Samples: The Distribution of Sample Means.

A sample of n = 4 scores is selected from a population with μ = 40 with σ = 8,and the sample mean is M = 43.What is the expected value for the sample mean?

Samples of size n = 9 are selected from a population with μ = 80 with σ = 18.What is the expected value for the distribution of sample means?

A sample is selected from a population with µ = 30 and σ = 10.If the sample mean of M = 34 corresponds to z = +2.00,then the sample size is n = 25.

In order for the distribution of sample means to be normal,it must be based on samples of at least n = 30 scores.

A sample of n = 4 scores is selected from a population with μ = 50 and σ = 12.If the sample mean is M = 56,what is the z-score for this sample mean?

On average,a sample of n = 16 scores will provide a better estimate of the population mean than you would get with a sample of n = 9 scores from the same population.

Find the z-score for the sample mean for each of the following samples obtained from a population with µ = 50 and σ = 12. A)M = 56 for a sample of n = 4 B)M = 42 for a sample of n = 9 C)M = 51 for a sample of n = 36

A sample of n = 4 scores is obtained from a population with μ = 70 and σ = 8.If the sample mean corresponds to a z-score of 2.00,what is the value of the sample mean?

A sample of n = 25 scores is selected from a population with μ = 70 and σ = 20.It is very unlikely that the sample mean will be greater than 72.

Which combination of factors will produce the largest value for the standard error?

A sample of n = 4 scores is selected from a normal population with a mean of µ = 50 and a standard deviation of σ = 20.What is the probability of obtaining a sample mean greater than M = 48?

A sample of n = 25 scores is selected from a population with a mean of µ = 80 and a standard deviation of σ = 20.The standard error for the sample mean is 20.

For a population with µ = 80 and σ = 20,the distribution of sample means based on n = 16 will have an expected value of and a standard error of .

A sample of n = 9 scores is randomly selected from a population with µ = 80 and ? = 9.If the sample mean is M = 83,then the corresponding z-score is z = +3.00.

If random samples,each with n = 9 scores,are selected from a normal population with µ = 80 and σ = 18,how much difference,on average,should there be between a sample mean and the population mean?

A sample of n = 36 scores is selected from a population with σ = 12.If the sample mean of M = 56 produces a z-score of z = +3.00,then what is the population mean?

If the sample size is equal to the population variance (n = σ²),then the standard error is equal to 1.

If a sample of n = 4 scores is obtained from a population with μ = 70 and σ = 12,what is the z-score corresponding to a sample mean of M = 73?

A sample obtained from a population with σ = 12 has a standard error of 2 points.How many scores are in the sample?

For a normal population with µ = 40 and σ = 10,which of the following samples has the highest probability of being obtained?