Question 1

If a correlation between two variables is -.2, the coefficient of determination is -.04

Accepted Answer

A) True 
 B)False  False

Question 2

Why is truncated range a problem when conducting correlational research?

Accepted Answer

There are two main reasons. The first is that the sample is not representative of the population. This then leads to the second problem, which is the sample correlation coefficient being underestimated.

Question 3

A researcher is examining whether the amount of time newborns can sleep without being disturbed is related to parental stress. The researcher asked 30 parents to report the longest amount of time in number of minutes their newborn child has been able to sleep without waking up. Then the parents were asked to rate their stress levels.
What is the critical value assuming α = .05?

Accepted Answer

A)  .367 
B)  .361 
C)  .463 
D)  .471 
A)  .367 
B)  .361 
C)  .463 
D)  .471 B

Question 4

In a regression equation, if a is negative, then the correlation between the predictor and outcome must be negatively correlated.

Accepted Answer

A) True 
 B)False

Question 5

Is a person's degree of extraversion a predictor of romantic partners? Below are normed data on individuals' degree of extraversion and the number of partners they've had.
 $$\begin{array} { c c } 
\hline \text { Extraversion } & \text { Partners } \
\hline 1.2 & 4 \
1.1 & 3 \
- 0.4 & 2 \
0.5 & 6 \
0.2 & 5 \
0.1 & 3 \
0 & 1 \
- 0.8 & 7 \
- 0.2 & 5 \
- 0.1 & 4 \
- 0.4 & 2 \
0.6 & 8 \
0.2 & 6 \
- 0.1 & 3 \
0.8 & 4 \
- 1 & 5 \
0.9 & 1 \
\hline
\end{array}$$ identify a potential hidden variable that may explain the variable that the researcher failed to take into account

Accepted Answer

Age, Socioeconomic s

Question 6

When testing a correlation, the null hypothesis states that there is no correlation

Accepted Answer

A) True 
 B)False

Question 7

Does money buy happiness? A research collected data on how much individuals spent for the holidays, and how satisfied they were with their holiday season, overall. Below are the data:
 $$\begin{array} { c c } 
\hline \text { Dollars } & \text { Satisfaction } \
\hline 100 & 4 \
140 & 7 \
130 & 3 \
190 & 4 \
120 & 7 \
100 & 4 \
150 & 8 \
140 & 2 \
160 & 9 \
180 & 10 \
70 & 5 \
120 & 7 \
90 & 2 \
70 & 4 \
\hline
\end{array}$$ how many degrees of freedom are there for the test?

Accepted Answer

The answer of Does money buy happiness? A research collected...

Question 8

The coefficient of determination is used to explain the proportion of variance shared between two variables

Accepted Answer

A) True 
 B)False

Question 9

Positive correlations are also described as indirect, whereas negative correlations are also described as direct.

Accepted Answer

A) True 
 B)False

Question 10

Which of the following is the strongest correlation?

Accepted Answer

A)  -.77 
B)  .08 
C)  .36 
D)  .72 
A)  -.77 
B)  .08 
C)  .36 
D)  .72

Question 11

When two variables have a coefficient of determination of .78, it suggests that…

Accepted Answer

A)  One variable has a 78% chance of causing the other variable. 
B)  The two variables share 78% variance 
C)  The two variables have a correlation of .78 
D)  The two variables have a regression line that has a slope of .78 
A)  One variable has a 78% chance of causing the other variable. 
B)  The two variables share 78% variance 
C)  The two variables have a correlation of .78 
D)  The two variables have a regression line that has a slope of .78

Question 12

A correlation of .78 is stronger than a correlation of -.92.

Accepted Answer

A) True 
 B)False

Question 13

If two variables are perfectly negatively correlated, their coefficient of determination would be…

Accepted Answer

A)  -1.00 
B)  1.00 
C)  0.00 
D)  .50 
A)  -1.00 
B)  1.00 
C)  0.00 
D)  .50

Question 14

Do high school grades predict college academic success? Below are data collected from some recent college graduates.
 $$\begin{array} { c c } 
\hline\text { high school GPA } & \begin{array} { c } 
\text { College } \
\text { GPA }
\end{array} \
\hline 3.4 & 3.2 \
2.8 & 3.6 \
2.9 & 3.1 \
3.1 & 3.4 \
3.6 & 3.6 \
3.8 & 3.5 \
3.4 & 2.9 \
3.6 & 3.3 \
3.3 & 3.8 \
3.3 & 3.5 \
3.1 & 3 \
3 & 3.1 \
3.6 & 3.7 \
3.7 & 3.9 \
2.6 & 3.1 \
2.2 & 3.2 \
2.8 & 2.7 \
3.1 & 3.5 \
3 & 3 \
\hline
\end{array}$$ What is the correlation?

Accepted Answer

The answer of Do high school grades predict college academic...

Question 15

When a truncated range occurs, which of the following is a likely result?

Accepted Answer

A)  The coefficient of determination is larger than the true value. 
B)  The correlation coefficient tends to over-estimate the true population value. 
C)  The correlation coefficient tends to under-estimated the true population value. 
D)  The correlation is more likely to be statistically significant. 
A)  The coefficient of determination is larger than the true value. 
B)  The correlation coefficient tends to over-estimate the true population value. 
C)  The correlation coefficient tends to under-estimated the true population value. 
D)  The correlation is more likely to be statistically significant.

Question 16

Which of the following statements best describes the coefficient of determination?

Accepted Answer

A)  It is a number constrained between -1.00 and 1.00 
B)  It is a number that varies from 0 to positive infinity 
C)  It is a number between 0 and 1.00 
D)  It is a percentage that represents the proportion of error variance explained by your independent variable. 
A)  It is a number constrained between -1.00 and 1.00 
B)  It is a number that varies from 0 to positive infinity 
C)  It is a number between 0 and 1.00 
D)  It is a percentage that represents the proportion of error variance explained by your independent variable.

Question 17

Which of the following best describes the relationship between statistics and causality?

Accepted Answer

A)  The method and statistic play equal roles in determining whether causal relationships are established. 
B)  The statistic is the most important piece of information that determines whether causality can be inferred. 
C)  The method is more important than the statistic for determining a causal relationship 
D)  Causality has to do with sample size, but not the method or statistic. If you have the entire population's data, the results are always causal. 
A)  The method and statistic play equal roles in determining whether causal relationships are established. 
B)  The statistic is the most important piece of information that determines whether causality can be inferred. 
C)  The method is more important than the statistic for determining a causal relationship 
D)  Causality has to do with sample size, but not the method or statistic. If you have the entire population's data, the results are always causal.

Question 18

Do high school grades predict college academic success? Below are data collected from some recent college graduates.
 $$\begin{array} { c c } 
\hline \text { high school GPA } & \begin{array} { c } 
\text { College } \
\text { GPA }
\end{array} \
\hline 3.4 & 3.2 \
2.8 & 3.6 \
2.9 & 3.1 \
3.1 & 3.4 \
3.6 & 3.6 \
3.8 & 3.5 \
3.4 & 2.9 \
3.6 & 3.3 \
3.3 & 3.8 \
3.3 & 3.5 \
3.1 & 3 \
3 & 3.1 \
3.6 & 3.7 \
3.7 & 3.9 \
2.6 & 3.1 \
2.2 & 3.2 \
2.8 & 2.7 \
3.1 & 3.5 \
3 & 3 \
\hline
\end{array}$$ What is the regression coefficient for the prediction?

Accepted Answer

The answer of Do high school grades predict college academic...

Question 19

In a regression equation, if b is positive, then the correlation between the predictor and outcome must be negatively correlated.

Accepted Answer

A) True 
 B)False

Question 20

Which of the following is beyond the scope of a Pearson correlation?

Accepted Answer

A)  calculating a linear relationship between two variables. 
B)  You can use it to determine how much one variable explains another variable. 
C)  Determine quadratic relationships between two variables 
D)  All of the above are correct. 
A)  calculating a linear relationship between two variables. 
B)  You can use it to determine how much one variable explains another variable. 
C)  Determine quadratic relationships between two variables 
D)  All of the above are correct.

If a correlation between two variables is -.2, the coefficient of determination is -.04

Why is truncated range a problem when conducting correlational research?

In a regression equation, if a is negative, then the correlation between the predictor and outcome must be negatively correlated.

When testing a correlation, the null hypothesis states that there is no correlation

The coefficient of determination is used to explain the proportion of variance shared between two variables

Positive correlations are also described as indirect, whereas negative correlations are also described as direct.

Which of the following is the strongest correlation?

When two variables have a coefficient of determination of .78, it suggests that…

A correlation of .78 is stronger than a correlation of -.92.

If two variables are perfectly negatively correlated, their coefficient of determination would be…

When a truncated range occurs, which of the following is a likely result?

Which of the following statements best describes the coefficient of determination?

Which of the following best describes the relationship between statistics and causality?

In a regression equation, if b is positive, then the correlation between the predictor and outcome must be negatively correlated.

Which of the following is beyond the scope of a Pearson correlation?

Introduction: Statistics--Who Needs Them

Types of Data

A Picture Is Worth a Thousand Words: Creating and Interpreting Graphics

Measures of Central Tendency: Whats so Average About the Mean

Variability: the Law of Life

Where Am I Normal Distributions and Standard Scores

Basic Probability Theory

The Central Limit Theorem and Hypothesis Testing

The Z-Test

The T-Test

Analysis of Variance

Confidence Intervals and Effect Size: Building a Better Mousetrap

The Chi-Square Test

Non-Parametric Tests

Which Test Should I Use and Why

Filters

Exam 13: Correlation and Regression: Are We Related

If a correlation between two variables is -.2, the coefficient of determination is -.04

Why is truncated range a problem when conducting correlational research?

In a regression equation, if a is negative, then the correlation between the predictor and outcome must be negatively correlated.

When testing a correlation, the null hypothesis states that there is no correlation

The coefficient of determination is used to explain the proportion of variance shared between two variables

Positive correlations are also described as indirect, whereas negative correlations are also described as direct.

Which of the following is the strongest correlation?

When two variables have a coefficient of determination of .78, it suggests that…

A correlation of .78 is stronger than a correlation of -.92.

If two variables are perfectly negatively correlated, their coefficient of determination would be…

When a truncated range occurs, which of the following is a likely result?

Which of the following statements best describes the coefficient of determination?

Which of the following best describes the relationship between statistics and causality?

In a regression equation, if b is positive, then the correlation between the predictor and outcome must be negatively correlated.

Which of the following is beyond the scope of a Pearson correlation?

Introduction: Statistics--Who Needs Them

Types of Data

A Picture Is Worth a Thousand Words: Creating and Interpreting Graphics

Measures of Central Tendency: Whats so Average About the Mean

Variability: the Law of Life

Where Am I Normal Distributions and Standard Scores

Basic Probability Theory

The Central Limit Theorem and Hypothesis Testing

The Z-Test

The T-Test

Analysis of Variance

Confidence Intervals and Effect Size: Building a Better Mousetrap

The Chi-Square Test

Non-Parametric Tests

Which Test Should I Use and Why

Filters