Question 1

Which of these strategies is MOST commonly used to decrease the probability of making a type II error?

Accepted Answer

A)  never rejecting the null hypothesis 
B)  increasing the sample size 
C)  lowering alpha 
D)  increasing the probability of making a type I error 
A)  never rejecting the null hypothesis 
B)  increasing the sample size 
C)  lowering alpha 
D)  increasing the probability of making a type I error B

Question 2

Calculate the r2 statistic for t = 3.41 and two groups of 20 individuals each.

Accepted Answer

A)  .08 
B)  .23 
C)  .37 
D)  .39 
A)  .08 
B)  .23 
C)  .37 
D)  .39 B

Question 3

Statistical power is the probability of ______.

Accepted Answer

A)  detecting an effect when it exists 
B)  detecting an effect when it does not exist 
C)  not detecting an effect when it exists 
D)  not detecting an effect when it does not exist 
A)  detecting an effect when it exists 
B)  detecting an effect when it does not exist 
C)  not detecting an effect when it exists 
D)  not detecting an effect when it does not exist A

Question 4

A type II error occurs when a researcher ______.

Accepted Answer

A)  correctly rejects the null hypothesis 
B)  says an effect does not exist when it in fact does 
C)  falsely concludes that an effect exists 
D)  rejects the null hypothesis when he should 
A)  correctly rejects the null hypothesis 
B)  says an effect does not exist when it in fact does 
C)  falsely concludes that an effect exists 
D)  rejects the null hypothesis when he should

Question 5

There exists the possibility of a ______ error whenever a researcher makes the decision to ______.

Accepted Answer

A)  type I; not reject the null hypothesis 
B)  type I; reject the alternative hypothesis 
C)  type II; not reject the null hypothesis 
D)  type II; reject the null hypothesis 
A)  type I; not reject the null hypothesis 
B)  type I; reject the alternative hypothesis 
C)  type II; not reject the null hypothesis 
D)  type II; reject the null hypothesis

Question 6

If there is no relationship between two variables, how much of the variance in one variable is explained by the other variable?

Accepted Answer

A)  0% 
B)  25% 
C)  50% 
D)  100% 
A)  0% 
B)  25% 
C)  50% 
D)  100%

Question 7

Calculate the r2 statistic for t = 3.11 and two groups of 10 individuals each.

Accepted Answer

A)  .15 
B)  .35 
C)  .49 
D)  .55 
A)  .15 
B)  .35 
C)  .49 
D)  .55

Question 8

An example of a Type I error is when a researcher concludes ______.

Accepted Answer

A)  an effect does not exist when it actually does 
B)  an effect exists when it actually doesn't 
C)  groups do not differ when they actually do 
D)  groups are the same when they're actually different 
A)  an effect does not exist when it actually does 
B)  an effect exists when it actually doesn't 
C)  groups do not differ when they actually do 
D)  groups are the same when they're actually different

Question 9

Within a college course, a ______ error occurs if an instructor decides a student ______ when he/she in fact ______.

Accepted Answer

A)  type I; has cheated; did cheat 
B)  type II; has not cheated; did cheat 
C)  type II; has cheated; did not cheat 
D)  type I; has not cheated; did not cheat 
A)  type I; has cheated; did cheat 
B)  type II; has not cheated; did cheat 
C)  type II; has cheated; did not cheat 
D)  type I; has not cheated; did not cheat

Question 10

Changing alpha (α) from .05 to .01 ______ the probability of making a type I error and ______ the probability of making a type II error.

Accepted Answer

A)  increases; increases 
B)  increases; decreases 
C)  decreases; increases 
D)  decreases; decreases 
A)  increases; increases 
B)  increases; decreases 
C)  decreases; increases 
D)  decreases; decreases

Question 11

When the within-group variability increases the value of the t-statistics increases, increasing the likelihood of ______.

Accepted Answer

A)  rejecting the null hypothesis 
B)  not rejecting the null hypothesis 
C)  rejecting the alternative hypothesis 
D)  increasing the between group variability 
A)  rejecting the null hypothesis 
B)  not rejecting the null hypothesis 
C)  rejecting the alternative hypothesis 
D)  increasing the between group variability

Question 12

According to Cohen, an r2 effect size of .24 may be considered to be a ______ effect.

Accepted Answer

A)  small 
B)  medium 
C)  large 
D)  nonsignificant 
A)  small 
B)  medium 
C)  large 
D)  nonsignificant

Question 13

The main concern with lowering the probability of making a type II error is that it ______.

Accepted Answer

A)  increases the probability of making a type I error 
B)  decreases the probability of making a type II error 
C)  changes the effect size 
D)  decreases the likelihood of finding effects when they in fact do not exist 
A)  increases the probability of making a type I error 
B)  decreases the probability of making a type II error 
C)  changes the effect size 
D)  decreases the likelihood of finding effects when they in fact do not exist

Question 14

Holding all else constant, increasing sample size ______ the probability of making a type I error and ______ the probability of making a type II error.

Accepted Answer

A)  increases; decreases 
B)  decreases; increases 
C)  does not affect; decreases 
D)  decreases; does not affect 
A)  increases; decreases 
B)  decreases; increases 
C)  does not affect; decreases 
D)  decreases; does not affect

Question 15

Calculate the r2 statistic for t = 4.64 with N = 50 for each of the two groups.

Accepted Answer

A)  .05 
B)  .18 
C)  .30 
D)  .31 
A)  .05 
B)  .18 
C)  .30 
D)  .31

Question 16

Lowering alpha from α = .05 to α = .01 is a way to reduce type I error.

Accepted Answer

A) True 
 B)False

Question 17

The concept of statistical power relates most directly to ______.

Accepted Answer

A)  type I error 
B)  type II error 
C)  effect size 
D)  t-tests 
A)  type I error 
B)  type II error 
C)  effect size 
D)  t-tests

Question 18

The r squared (r2) statistic may be defined as ______.

Accepted Answer

A)  the variation in one variable 
B)  the percentage of the standard deviation in one variable that is accounted for by another 
C)  the percentage of the mean difference in one variable that is accounted for by another variable 
D)  the percentage of variance in one variable that is accounted for by another variable 
A)  the variation in one variable 
B)  the percentage of the standard deviation in one variable that is accounted for by another 
C)  the percentage of the mean difference in one variable that is accounted for by another variable 
D)  the percentage of variance in one variable that is accounted for by another variable

Question 19

Calculate Cohen's d for t = 2.12 with N = 25 for each of the two groups.

Accepted Answer

A)  .09 
B)  .31 
C)  .61 
D)  .88 
A)  .09 
B)  .31 
C)  .61 
D)  .88

Question 20

Within a marriage, a ______ error occurs if someone decides their spouse ______ when in fact he/she ______.

Accepted Answer

A)  type I; has not been unfaithful; has been unfaithful 
B)  type II; has not been unfaithful; has not been unfaithful 
C)  type I; has been unfaithful; has not been unfaithful 
D)  type II; has been unfaithful; has been unfaithful 
A)  type I; has not been unfaithful; has been unfaithful 
B)  type II; has not been unfaithful; has not been unfaithful 
C)  type I; has been unfaithful; has not been unfaithful 
D)  type II; has been unfaithful; has been unfaithful

Which of these strategies is MOST commonly used to decrease the probability of making a type II error?

Calculate the r² statistic for t = 3.41 and two groups of 20 individuals each.

Statistical power is the probability of ______.

A type II error occurs when a researcher ______.

There exists the possibility of a error whenever a researcher makes the decision to .

If there is no relationship between two variables, how much of the variance in one variable is explained by the other variable?

Calculate the r² statistic for t = 3.11 and two groups of 10 individuals each.

An example of a Type I error is when a researcher concludes ______.

Within a college course, a error occurs if an instructor decides a student when he/she in fact __.

Changing alpha (α) from .05 to .01 the probability of making a type I error and the probability of making a type II error.

When the within-group variability increases the value of the t-statistics increases, increasing the likelihood of ______.

According to Cohen, an r² effect size of .24 may be considered to be a ______ ^effect.

The main concern with lowering the probability of making a type II error is that it ______.

Holding all else constant, increasing sample size the probability of making a type I error and the probability of making a type II error.

Calculate the r² statistic for t = 4.64 with N = 50 for each of the two groups.

Lowering alpha from α = .05 to α = .01 is a way to reduce type I error.

The concept of statistical power relates most directly to ______.

The r squared (r²) statistic may be defined as ______.

Calculate Cohen's d for t = 2.12 with N = 25 for each of the two groups.

Within a marriage, a error occurs if someone decides their spouse when in fact he/she __.

Introduction to Statistics

Examining Data: Tables and Figures

Measures of Central Tendency

Measures of Variability

Normal Distributions

Probability and Hypothesis Testing

Testing One Sample Mean

Estimating the Mean of a Population

Testing the Difference Between Two Means

One-Way Analysis of Variance Anova

Two-Way Analysis of Variance Anova

Correlation

Linear Regression and Multiple Correlation

Chi-Square

Filters

Exam 10: Errors in Hypothesis Testing, Statistical Power, and Effect Size

Which of these strategies is MOST commonly used to decrease the probability of making a type II error?

Calculate the r2 statistic for t = 3.41 and two groups of 20 individuals each.

Statistical power is the probability of ______.

A type II error occurs when a researcher ______.

There exists the possibility of a ______ error whenever a researcher makes the decision to ______.

If there is no relationship between two variables, how much of the variance in one variable is explained by the other variable?

Calculate the r2 statistic for t = 3.11 and two groups of 10 individuals each.

An example of a Type I error is when a researcher concludes ______.

Within a college course, a ______ error occurs if an instructor decides a student ______ when he/she in fact ______.

Changing alpha (α) from .05 to .01 ______ the probability of making a type I error and ______ the probability of making a type II error.

When the within-group variability increases the value of the t-statistics increases, increasing the likelihood of ______.

According to Cohen, an r2 effect size of .24 may be considered to be a ______ effect.

The main concern with lowering the probability of making a type II error is that it ______.

Holding all else constant, increasing sample size ______ the probability of making a type I error and ______ the probability of making a type II error.

Calculate the r2 statistic for t = 4.64 with N = 50 for each of the two groups.

Lowering alpha from α = .05 to α = .01 is a way to reduce type I error.

The concept of statistical power relates most directly to ______.

The r squared (r2) statistic may be defined as ______.

Calculate Cohen's d for t = 2.12 with N = 25 for each of the two groups.

Within a marriage, a ______ error occurs if someone decides their spouse ______ when in fact he/she ______.

Introduction to Statistics

Examining Data: Tables and Figures

Measures of Central Tendency

Measures of Variability

Normal Distributions

Probability and Hypothesis Testing

Testing One Sample Mean

Estimating the Mean of a Population

Testing the Difference Between Two Means

One-Way Analysis of Variance Anova

Two-Way Analysis of Variance Anova

Correlation

Linear Regression and Multiple Correlation

Chi-Square

Filters

Calculate the r² statistic for t = 3.41 and two groups of 20 individuals each.

There exists the possibility of a error whenever a researcher makes the decision to .

Calculate the r² statistic for t = 3.11 and two groups of 10 individuals each.

Within a college course, a error occurs if an instructor decides a student when he/she in fact __.

Changing alpha (α) from .05 to .01 the probability of making a type I error and the probability of making a type II error.

According to Cohen, an r² effect size of .24 may be considered to be a ______ ^effect.

Holding all else constant, increasing sample size the probability of making a type I error and the probability of making a type II error.

Calculate the r² statistic for t = 4.64 with N = 50 for each of the two groups.

The r squared (r²) statistic may be defined as ______.

Within a marriage, a error occurs if someone decides their spouse when in fact he/she __.