Question 1

The probability of making a type I error may be represented by ______.

Accepted Answer

A)  α 
B)  1 - t 
C)  β 
D)  1 - β 
A)  α 
B)  1 - t 
C)  β 
D)  1 - β

Question 2

Which of the following would be considered a 'medium' effect size according to Cohen?

Accepted Answer

A)  r2 = .09 
B)  r2 = .20 
C)  r2 = .03 
D)  r2 = .28 
A)  r2 = .09 
B)  r2 = .20 
C)  r2 = .03 
D)  r2 = .28

Question 3

Cohen's d is an estimate of ______.

Accepted Answer

A)  the difference between the mean and the population in standard deviation units 
B)  the magnitude of the difference between the means of two groups measured in standard deviation units 
C)  the magnitude of the difference between the means of two groups measured in standard error units 
D)  the magnitude of the difference between the means of two groups measured in z-score units 
A)  the difference between the mean and the population in standard deviation units 
B)  the magnitude of the difference between the means of two groups measured in standard deviation units 
C)  the magnitude of the difference between the means of two groups measured in standard error units 
D)  the magnitude of the difference between the means of two groups measured in z-score units

Question 4

Why is the term "highly significant" inappropriate to use when interpreting the probability?

Accepted Answer

A)  because statistical significance is a dichotomy 
B)  because statistical significance is on a continuum 
C)  because p < .001 is less significant than p < .01 
D)  because p < .001 is 'better' than p < .01 
A)  because statistical significance is a dichotomy 
B)  because statistical significance is on a continuum 
C)  because p < .001 is less significant than p < .01 
D)  because p < .001 is 'better' than p < .01

Question 5

A measure of effect size is a statistic that measures the ______.

Accepted Answer

A)  direction of the relationship between variables 
B)  nature of the relationship between variables 
C)  magnitude of the relationship between the sample and population 
D)  magnitude of the relationship between variables 
A)  direction of the relationship between variables 
B)  nature of the relationship between variables 
C)  magnitude of the relationship between the sample and population 
D)  magnitude of the relationship between variables

Question 6

Reducing the likelihood of making a type II error involves ______.

Accepted Answer

A)  changing the research hypothesis 
B)  increasing the likelihood of rejecting the null hypothesis 
C)  decreasing the likelihood of rejecting the null hypothesis 
D)  never rejecting the null hypothesis 
A)  changing the research hypothesis 
B)  increasing the likelihood of rejecting the null hypothesis 
C)  decreasing the likelihood of rejecting the null hypothesis 
D)  never rejecting the null hypothesis

Question 7

A type I error may occur when a researcher makes the decision to ______.

Accepted Answer

A)  reject the null hypothesis 
B)  fail to reject the null hypothesis 
C)  support the alternative hypothesis 
D)  prove the research hypothesis 
A)  reject the null hypothesis 
B)  fail to reject the null hypothesis 
C)  support the alternative hypothesis 
D)  prove the research hypothesis

Question 8

A significance level of p < .01 is not "highly" significant compared to a significance level of p < .05.

Accepted Answer

A) True 
 B)False

Question 9

A Cohen's d value of 1.03 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 10

Calculate the r2 statistic for t = 2.98 and two groups of 15 individuals each.

Accepted Answer

A)  .10 
B)  .24 
C)  .37 
D)  .41 
A)  .10 
B)  .24 
C)  .37 
D)  .41

Question 11

The chances of making a type I error is typically equal to ______.

Accepted Answer

A)  the probability of rejecting the null hypothesis 
B)  .95 
C)  the region of non-rejection 
D)  μ 
A)  the probability of rejecting the null hypothesis 
B)  .95 
C)  the region of non-rejection 
D)  μ

Question 12

The probability of making a type I error is typically equal to ______.

Accepted Answer

A)  α 
B)  β 
C)  .95 
D)  μ 
A)  α 
B)  β 
C)  .95 
D)  μ

Question 13

A Cohen's d value of .60 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 14

Which of the following is a range of possible values for a measure of effect size?

Accepted Answer

A)  50%-75% 
B)  25%-75% 
C)  10%-90% 
D)  0%-100% 
A)  50%-75% 
B)  25%-75% 
C)  10%-90% 
D)  0%-100%

Question 15

How would a researcher interpret an r2 value of .43?

Accepted Answer

A)  5.7% of the variance in one variable is explained by another variable. 
B)  57% of the variance in one variable is explained by another variable. 
C)  43% of the variance in one variable is explained by another variable. 
D)  4.3% of the variance in one variable is explained by another variable. 
A)  5.7% of the variance in one variable is explained by another variable. 
B)  57% of the variance in one variable is explained by another variable. 
C)  43% of the variance in one variable is explained by another variable. 
D)  4.3% of the variance in one variable is explained by another variable.

Question 16

How would a researcher interpret an r2 value of .27?

Accepted Answer

A)  27% of the variance in one variable is explained by another variable. 
B)  73% of the variance in one variable is explained by another variable. 
C)  2.7% of the variance in one variable is explained by another variable. 
D)  .27% of the variance in one variable is explained by another variable. 
A)  27% of the variance in one variable is explained by another variable. 
B)  73% of the variance in one variable is explained by another variable. 
C)  2.7% of the variance in one variable is explained by another variable. 
D)  .27% of the variance in one variable is explained by another variable.

Question 17

A ______ error may be characterized as ______.

Accepted Answer

A)  type I; saying an effect exists when it does not 
B)  type II; rejecting a true null hypothesis 
C)  type I; saying an effect does not exist when it does 
D)  type II; rejecting a false null hypothesis 
A)  type I; saying an effect exists when it does not 
B)  type II; rejecting a true null hypothesis 
C)  type I; saying an effect does not exist when it does 
D)  type II; rejecting a false null hypothesis

Question 18

A Cohen's d value of .25 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 19

If there is a "perfect" 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 20

A type I error occurs when a researcher ______.

Accepted Answer

A)  does not reject the null hypothesis when he should 
B)  rejects the alternative hypothesis 
C)  rejects a true null hypothesis 
D)  concludes an effect does not exists when it does 
A)  does not reject the null hypothesis when he should 
B)  rejects the alternative hypothesis 
C)  rejects a true null hypothesis 
D)  concludes an effect does not exists when it does

The probability of making a type I error may be represented by ______.

Which of the following would be considered a 'medium' effect size according to Cohen?

Cohen's d is an estimate of ______.

Why is the term "highly significant" inappropriate to use when interpreting the probability?

A measure of effect size is a statistic that measures the ______.

Reducing the likelihood of making a type II error involves ______.

A type I error may occur when a researcher makes the decision to ______.

A significance level of p < .01 is not "highly" significant compared to a significance level of p < .05.

A Cohen's d value of 1.03 may be considered to be a ______ effect.

Calculate the r² statistic for t = 2.98 and two groups of 15 individuals each.

The chances of making a type I error is typically equal to ______.

The probability of making a type I error is typically equal to ______.

A Cohen's d value of .60 may be considered to be a ______ effect.

Which of the following is a range of possible values for a measure of effect size?

How would a researcher interpret an r² value of .43?

How would a researcher interpret an r² value of .27?

A error may be characterized as .

A Cohen's d value of .25 may be considered to be a ______ effect.

If there is a "perfect" relationship between two variables, how much of the variance in one variable is explained by the other variable?

A type I error occurs when a researcher ______.

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

The probability of making a type I error may be represented by ______.

Which of the following would be considered a 'medium' effect size according to Cohen?

Cohen's d is an estimate of ______.

Why is the term "highly significant" inappropriate to use when interpreting the probability?

A measure of effect size is a statistic that measures the ______.

Reducing the likelihood of making a type II error involves ______.

A type I error may occur when a researcher makes the decision to ______.

A significance level of p < .01 is not "highly" significant compared to a significance level of p < .05.

A Cohen's d value of 1.03 may be considered to be a ______ effect.

Calculate the r2 statistic for t = 2.98 and two groups of 15 individuals each.

The chances of making a type I error is typically equal to ______.

The probability of making a type I error is typically equal to ______.

A Cohen's d value of .60 may be considered to be a ______ effect.

Which of the following is a range of possible values for a measure of effect size?

How would a researcher interpret an r2 value of .43?

How would a researcher interpret an r2 value of .27?

A ______ error may be characterized as ______.

A Cohen's d value of .25 may be considered to be a ______ effect.

If there is a "perfect" relationship between two variables, how much of the variance in one variable is explained by the other variable?

A type I error occurs when a researcher ______.

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 = 2.98 and two groups of 15 individuals each.

How would a researcher interpret an r² value of .43?

How would a researcher interpret an r² value of .27?

A error may be characterized as .