Deck 10: Correlation

Question 1

In statistics, r is called:

A)Yate's correction.
B)Franklin's fudge factor.
C)Pearson's correlation coefficient.
D)Pearson's correlation correction.

Answer 1

Pearson's correlation coefficient.

Question 2

The strength of a correlation is indicated by:

A)its sign (+ or - ).
B)its numerical value.
C)both a and b
D)none of the above

Answer 2

its numerical value.

Question 3

Choose the weakest correlation:

A)-.28
B)-.76
C)+.66
D)+.1 2

Answer 3

+.1 2

Question 4

If the variable Crime increases as the variable Police decreases, the correlation is said to Be:

A)positive.
B)negative.
C)weak.
D )curvilinear.

Question 5

A strong straight-line correlation between variables X and Y implies:

A)high scores on X are associated with high scores on Y.
B)low scores on X are associated with low scores on Y.
C)X is a good predictor of Y.
D)X is not good predictor of Y.

Question 6

If the variable Tasty remains constant as variable Cost increases, the correlation is said to Be:

A)positive.
B)negative.
C)weak.
D)zero.

Question 7

An important first step to visualize the relationship of two interval level variables is to:

A)calculate a correlation coefficient.
B)look at a scatter plot.
C)do a test of significance.
D)calculate the variance of the independent variable.

Question 8

Choose the strongest correlation:

A)-.28
B)-.76
C)+.66
D)+.1 2

Question 9

If a correlation between variables A and B is found to be equal to -1.16:

A)the relationship is negative.
B)the relationship is significant.
C)there has been a miscalculation.
D)none of the above

Question 10

If TV viewing initially decreases with age, but then after age 40 reverses itself, this Correlation would be an example of:

A)a positive relationship.
B)a negative relationship.
C)a curvilinear relationship.
D )cannot tell from the above information

Question 11

The strength of the correlation is indicated by:

A)its sign (+ or - ).
B)its numerical value.
C)both a and b
D)none of the above

Question 12

The correlation coefficient:

A)presents the strength of the relationship.
B)presents the direction of the relationship.
C)varies from -1.0 to +1.0.
D)all of the above

Question 13

Correlation can vary with respect to:

A)time.
B)direction.
C)strength.
D)b and c

Question 14

Which statement is NOT true of correlation coefficients?

A)Correlations can never exceed 1.0.
B)Correlations provide statements of causation.
C)Correlations can be negative.
D )All of the above are true.

Question 15

If the variable Wealth increases as the variable Education increases, the correlation is said To be:

A)positive.
B)negative.
C)strong.
D )curvilinear.

Question 16

Pearson's r is useful for detecting a relationship that is:

A)strong and positive.
B)strong and negative.
C)curvilinear.
D)a and b

Question 17

A negative correlation between variables X and Y implies:

A)high scores on X are associated with high scores on Y.
B)high scores on X are associated with low scores on Y.
C)low scores on X are associated with low scores on Y.
D)the variables X and Y are not strongly related.

Question 18

A positive correlation between variables X and Y implies:

A)high scores on X are associated with high scores on Y.
B)high scores on X are associated with low scores on Y.
C)low scores on X are associated with high scores on Y.
D)the variables X and Y are not strongly related.

Question 19

If the variable Attractiveness increases as the variable Weight remains constant, the Correlation is said to be:

A)positive.
B)negative.
C)strong.
D)zero.

Question 20

The direction of a correlation is indicated by:

A)its sign (+ or - ).
B)its numerical value.
C)both a and b
D)none of the above

Question 21

A weak correlation coefficient could result from a curvilinear relationship.

Question 22

The population correlation is known as:

A)row (ρ)
B)rho (ρ)
C)roe (θ)
D)theta (θ)

Question 23

The question below refers to the following information:
A professor is interested in knowing if the number of absences a student has during the semester is a good indication of how well a student does on the final exam. At the end of the year, the professor compares absence rates and exam grades for eight students. The data she found are as follows:
Is the correlation statistically significant and, if so, at what level?

Question 24

The question below refers to the following information:
A professor is interested in knowing if the number of absences a student has during the semester is a good indication of how well a student does on the final exam. At the end of the year, the professor compares absence rates and exam grades for eight students. The data she found are as follows:
Calculate t in order to see if the correlation is statistically significant.

Question 25

Pearson's r is only useful for detecting a __________ line relationship.

Question 26

Testing the significance of Pearson's r requires both X and Y variables to be __________ distributed in the population.

Question 27

The question below refers to the following information:
A professor is interested in knowing if the number of absences a student has during the semester is a good indication of how well a student does on the final exam. At the end of the year, the professor compares absence rates and exam grades for eight students. The data she found are as follows:
The correlation for the above data has a __________ direction.

Question 28

The closer the correlation coefficient is to __________, the weaker the correlation.

Question 29

A correlation coefficient of -.60 is a stronger correlation than a correlation coefficient of +.55

Question 30

The closer the correlation coefficient is to 1 or -1, the __________ the correlation.

Question 31

The question below refers to the following information:
A professor is interested in knowing if the number of absences a student has during the semester is a good indication of how well a student does on the final exam. At the end of the year, the professor compares absence rates and exam grades for eight students. The data she found are as follows:
What is the research hypothesis?

Question 32

The question below refers to the following information:
A professor is interested in knowing if the number of absences a student has during the semester is a good indication of how well a student does on the final exam. At the end of the year, the professor compares absence rates and exam grades for eight students. The data she found are as follows:
Calculate the Pearson's correlation coefficient.

Question 33

Pearson's correlation coefficient assesses the strength and direction of curvilinear relationships.

Question 34

A Person's r of .71 for Age and Attention Span would be an example of a __________ correlation.

Question 35

Correlation coefficients do NOT indicate the strength of a relationship.

Question 36

__________ correlations have a Pearson's r of 1 or -1.

Question 37

For Pearson's r, both X and Y variables must be measured at the __________ level.

Question 38

A Person's r of -.86 for Bigotry and Attractiveness would be an example of a __________ correlation.

Question 39

To calculate for the significance of Pearson's r, one can use the __________ ratio.

Question 40

The question below refers to the following information:
A professor is interested in knowing if the number of absences a student has during the semester is a good indication of how well a student does on the final exam. At the end of the year, the professor compares absence rates and exam grades for eight students. The data she found are as follows:
What is the null hypothesis?

Question 41

Calculate the Pearson's correlation coefficient for the following set of matched (x,y) data:
(4,6) (4,9) (3,5) (5,3) (9,4) (7,7)

Question 42

Calculate the Pearson's r of the following set of data:

Question 43

An administrator at a university is interested in studying the relationship between student satisfaction at the university(on a 1-10 scale) and the student's GPA. Here are the data she collected:
Compute the Pearson's r and test the significance of the obtained correlation (use α = .05) using Table F of Appendix C.

Question 44

The question below refers to the following information:
A professor is interested in knowing if the number of absences a student has during the semester is a good indication of how well a student does on the final exam. At the end of the year, the professor compares absence rates and exam grades for eight students. The data she found are as follows:
What are your conclusions about the null hypothesis?

Question 45

The question below refers to the following situation:
A social researcher is interested in studying the relationship between years of education and income. Here are the data he is working with:
Test the significance of the obtained correlation (use α = .05) using Table F of Appendix C.

Question 46

Use the following data to calculate the Pearson's r and test the significance of the obtained correlation (use α = .05) using Table F of Appendix C:

Question 47

The question below refers to the following situation:
A social researcher is interested in studying the relationship between years of education and income. Here are the data he is working with:
Compute the appropriate correlation coefficient.