Question 1

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

Accepted Answer

A) It is always normal. 
B) only if the population distribution is normal 
C) if the sample size is greater than 30 
D) if the population is normal or if the sample size is greater than 30. 
A) It is always normal. 
B) only if the population distribution is normal 
C) if the sample size is greater than 30 
D) if the population is normal or if the sample size is greater than 30. D

Question 2

If the sample size is equal to the population standard deviation (n = $\sigma$), then the standard error for the sample mean is equal to 1.00.

Accepted Answer

A) True 
 B)False  False

Question 3

For a particular population a sample of n = 4 scores has an expected value of 10.For the same population, a sample of n = 25 scores would have an expected value of _____.

Accepted Answer

A) 4 
B) 8 
C) 10 
D) 20 
A) 4 
B) 8 
C) 10 
D) 20 C

Question 4

The mean for a sample of n = 9 scores has a standard error of 2 points.This sample was selected from a population with a standard deviation of σ = 18.

Accepted Answer

A) True 
 B)False

Question 5

For a normal population with a mean of µ = 80 and a standard deviation of σ = 10, what is the probability of obtaining a sample mean greater than M = 75 for a sample of n = 25 scores?

Accepted Answer

A) p = 0.0062 
B) p = 0.9938 
C) p = 0.3085 
D) p = 0.6915 
A) p = 0.0062 
B) p = 0.9938 
C) p = 0.3085 
D) p = 0.6915

Question 6

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 smaller than 72.

Accepted Answer

A) True 
 B)False

Question 7

For a normal population with µ = 40 and σ = 10 which of the following samples is least likely to be obtained?

Accepted Answer

A) M ≤ 42 for a sample of n = 4 
B) M ≤ 44 for a sample of n = 4 
C) M ≤ 42 for a sample of n = 100 
D) M ≤ 44 for a sample of n = 100 
A) M ≤ 42 for a sample of n = 4 
B) M ≤ 44 for a sample of n = 4 
C) M ≤ 42 for a sample of n = 100 
D) M ≤ 44 for a sample of n = 100

Question 8

A sample of n = 4 scores is selected from a population with μ = 30 and σ = 8.The probability of obtaining a sample mean greater than 34 is equal to the probability of obtaining a z-score greater than z = 2.00 from a normal distribution.

Accepted Answer

A) True 
 B)False

Question 9

A sample of n = 9 scores is selected from a normal population with a mean of µ = 80 and a standard deviation of σ = 12.The probability that the sample mean will be greater than M = 86 is equal to the probability of obtaining a z-score greater than z = 1.50

Accepted Answer

A) True 
 B)False

Question 10

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

Accepted Answer

A) True 
 B)False

Question 11

A sample of n = 100 scores is selected from a population with μ = 80 with σ = 20.On average, how much error is expected between the sample mean and the population mean?

Accepted Answer

A) 0.2 points 
B) 0.8 points 
C) 2 points 
D) 4 points 
A) 0.2 points 
B) 0.8 points 
C) 2 points 
D) 4 points

Question 12

If samples are selected from a normal population, the distribution of sample means will also be normal.

Accepted Answer

A) True 
 B)False

Question 13

The distribution of sample means ____ .

Accepted Answer

A) is always a normal distribution. 
B) will be normal only if the population distribution is normal. 
C) will be normal only if the sample size is at least n = 30. 
D) we be normal if either the population is normal or the sample size is n > 30. 
A) is always a normal distribution. 
B) will be normal only if the population distribution is normal. 
C) will be normal only if the sample size is at least n = 30. 
D) we be normal if either the population is normal or the sample size is n > 30.

Question 14

The mean for a sample of n = 4 scores has a standard error σ = 5 points.This sample was selected from a population with a standard deviation of σ = 20.

Accepted Answer

A) True 
 B)False

Question 15

A sample from a population with μ = 40 and σ = 10 has a mean of M = 44.If the sample mean corresponds to a z = 2.00, then how many scores are in the sample?

Accepted Answer

A) n = 100 
B) n = 25 
C) n = 5 
D) n = 4 
A) n = 100 
B) n = 25 
C) n = 5 
D) n = 4

Question 16

A sample is obtained from a population with σ = 20.If the sample mean has a standard error of 5 points, then the sample size is n = 4.

Accepted Answer

A) True 
 B)False

Question 17

What term is used to identify the mean of the distribution of sample means?

Accepted Answer

A) the expected value of M 
B) the standard error of M 
C) the sample mean 
D) the central limit mean 
A) the expected value of M 
B) the standard error of M 
C) the sample mean 
D) the central limit mean

Question 18

According to the central limit theorem, the standard error for a sample mean becomes smaller as the sample size increases.

Accepted Answer

A) True 
 B)False

Question 19

What happens to the standard error of M as sample size increases?

Accepted Answer

A) It also increases. 
B) It decreases. 
C) It stays constant. 
D) The standard error does not change in a predictable manner when sample size increases. 
A) It also increases. 
B) It decreases. 
C) It stays constant. 
D) The standard error does not change in a predictable manner when sample size increases.

Question 20

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

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

If the sample size is equal to the population standard deviation (n = $\sigma$ ), then the standard error for the sample mean is equal to 1.00.

For a particular population a sample of n = 4 scores has an expected value of 10.For the same population, a sample of n = 25 scores would have an expected value of _____.

The mean for a sample of n = 9 scores has a standard error of 2 points.This sample was selected from a population with a standard deviation of σ = 18.

For a normal population with a mean of µ = 80 and a standard deviation of σ = 10, what is the probability of obtaining a sample mean greater than M = 75 for a sample of n = 25 scores?

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 smaller than 72.

For a normal population with µ = 40 and σ = 10 which of the following samples is least likely to be obtained?

A sample of n = 4 scores is selected from a population with μ = 30 and σ = 8.The probability of obtaining a sample mean greater than 34 is equal to the probability of obtaining a z-score greater than z = 2.00 from a normal distribution.

A sample of n = 9 scores is selected from a normal population with a mean of µ = 80 and a standard deviation of σ = 12.The probability that the sample mean will be greater than M = 86 is equal to the probability of obtaining a z-score greater than z = 1.50

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

A sample of n = 100 scores is selected from a population with μ = 80 with σ = 20.On average, how much error is expected between the sample mean and the population mean?

If samples are selected from a normal population, the distribution of sample means will also be normal.

The distribution of sample means ____ .

The mean for a sample of n = 4 scores has a standard error σ = 5 points.This sample was selected from a population with a standard deviation of σ = 20.

A sample from a population with μ = 40 and σ = 10 has a mean of M = 44.If the sample mean corresponds to a z = 2.00, then how many scores are in the sample?

A sample is obtained from a population with σ = 20.If the sample mean has a standard error of 5 points, then the sample size is n = 4.

What term is used to identify the mean of the distribution of sample means?

According to the central limit theorem, the standard error for a sample mean becomes smaller as the sample size increases.

What happens to the standard error of M as sample size increases?

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

Introduction to Statistics

Frequency Distributions

Central Tendency

Variability

Z-Scores

Probability

Introduction to Hypothesis Testing

Introduction to the T Statistic

The T Test for Two Independent Samples

The T Test for Two Related Samples

Introduction to Analysis of Variance

Repeated-Measures Anova

Two-Factor Analysis of Variance

Correlation

Introduction to Regression

Chi-Square Tests

The Binomial Test

Choosing the Right Statistics

Filters

Exam 7: The Distribution of Sample Means

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

If the sample size is equal to the population standard deviation (n = σ\sigmaσ ), then the standard error for the sample mean is equal to 1.00.

For a particular population a sample of n = 4 scores has an expected value of 10.For the same population, a sample of n = 25 scores would have an expected value of _____.

The mean for a sample of n = 9 scores has a standard error of 2 points.This sample was selected from a population with a standard deviation of σ = 18.

For a normal population with a mean of µ = 80 and a standard deviation of σ = 10, what is the probability of obtaining a sample mean greater than M = 75 for a sample of n = 25 scores?

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 smaller than 72.

For a normal population with µ = 40 and σ = 10 which of the following samples is least likely to be obtained?

A sample of n = 4 scores is selected from a population with μ = 30 and σ = 8.The probability of obtaining a sample mean greater than 34 is equal to the probability of obtaining a z-score greater than z = 2.00 from a normal distribution.

A sample of n = 9 scores is selected from a normal population with a mean of µ = 80 and a standard deviation of σ = 12.The probability that the sample mean will be greater than M = 86 is equal to the probability of obtaining a z-score greater than z = 1.50

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

A sample of n = 100 scores is selected from a population with μ = 80 with σ = 20.On average, how much error is expected between the sample mean and the population mean?

If samples are selected from a normal population, the distribution of sample means will also be normal.

The distribution of sample means ____ .

The mean for a sample of n = 4 scores has a standard error σ = 5 points.This sample was selected from a population with a standard deviation of σ = 20.

A sample from a population with μ = 40 and σ = 10 has a mean of M = 44.If the sample mean corresponds to a z = 2.00, then how many scores are in the sample?

A sample is obtained from a population with σ = 20.If the sample mean has a standard error of 5 points, then the sample size is n = 4.

What term is used to identify the mean of the distribution of sample means?

According to the central limit theorem, the standard error for a sample mean becomes smaller as the sample size increases.

What happens to the standard error of M as sample size increases?

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

Introduction to Statistics

Frequency Distributions

Central Tendency

Variability

Z-Scores

Probability

Introduction to Hypothesis Testing

Introduction to the T Statistic

The T Test for Two Independent Samples

The T Test for Two Related Samples

Introduction to Analysis of Variance

Repeated-Measures Anova

Two-Factor Analysis of Variance

Correlation

Introduction to Regression

Chi-Square Tests

The Binomial Test

Choosing the Right Statistics

Filters

If the sample size is equal to the population standard deviation (n = $\sigma$ ), then the standard error for the sample mean is equal to 1.00.