Workshop 5 Correlation Analysis Name: _______________________________________ Date Completed: _____________ |

Provide all solutions, answers and requested outputs after each question.

**Questions 1** & 2: (a) Compute the Pearson correlation for
the following set of data:

X |
0 |
1 |
2 |
3 |
4 |

Y |
3 |
1 |
5 |
9 |
7 |

(b) Add 5 points to each *X* value, and compute the Person
correlation again.

(c) When you add a constant to each score, what happens to *SS*
for *X* and *Y*?

What happens to the correlation between *X*
and *Y*?

(d) Now multiply each *X* in the original data by 3, and
compute the Pearson correlation again.

(e) When you multiply by a constant, what happens to *SS* for *X*
and *Y*?

What happens to the correlation between *X*
and *Y*?

**Question 3 & 4:** Correlation studies are often used to
help determine whether certain characteristics

are controlled more by genetic
influences or by environmental influences. These studies often examine

adopted children and compare
their behavior with the behavior**s **of their birth parents and
their

adoptive parents. One study
examined how much time individuals spend watching TV (Plomin, Corley,

Defries, & Fulker, 1990). The
following data are similar to results obtained in the study.

Amount of Time Spent Watching TV | ||

Adopted Children | Birth Parents | Adoptive Parents |

2 |
0 |
1 |

3 |
3 |
4 |

6 |
4 |
2 |

1 |
1 |
0 |

3 |
1 |
0 |

0 |
2 |
3 |

5 |
3 |
2 |

2 |
1 |
3 |

5 |
3 |
3 |

(a) What do scatter plots tell us about the relationships of TV
watching between children and their

birth and children and their adoptive
parents?

(b) Compute the Spearman correlation between the children and their birth parents.

(c) Compute the Spearman correlation between the children and their adoptive parents.

(d) Based on the two correlations, does TV watching appear to be
inherited from the birth parents or

is it learned from the adoptive parents?

**Question 5 & 6: **(a) Compute both the Pearson and
Spearman correlation for the Father's Education (FAED)

and Mother's Education (MAED) variables for the
HSB500.csv data set.

(b) What do the correlation tells us about the relationship between these two variables?

**Question 7 & 8:** A researcher has developed a new test of
self-esteem. To evaluate the reliability of the test,

the researcher obtains a sample of *n*
= 8 participants. each individual takes the test on a

Monday morning, then returns 2 weeks
later to take the test again. The two scores for the individual

are reported in the following table.

First Test |
13 | 5 | 12 | 11 | 9 | 14 | 8 | 8 |

Second Test |
15 | 4 | 13 | 11 | 10 | 13 | 8 | 6 |

(a) Which of the two correlation methods (Pearson or Spearman) is the best approach for this analysis and why?

(b) Using an appropriate correlation computational formula, what is
the correlation between the first and

second measure for this sample?

(c) Is the correlation between the two tests small, medium or large? Give justifications for your conclusion.

**Question 9 & 10:** It is well known that similarity in
attitudes, beliefs, and interests plays an important role

interpersonal attraction (see Byrne, 1971, for
example). Therefore, correlations for attitudes between married

couples should be strong. Suppose a researcher
developed a questionnaire that measures how liberal or

conservative one's attitudes are. Low scores
indicates that the person has liberal attitudes, whereas high

scores indicate conservatism. The following
hypothetical data are scores for married couples.

Couple | Wife | Husband |

A | 11 | 14 |

D | 6 | 7 |

C | 16 | 15 |

D | 4 | 7 |

E | 1 | 3 |

F | 10 | 9 |

G | 5 | 9 |

H | 3 | 8 |

(a) Compute Pearson correlation using a formula

(b) Compute Pearson using statistical packages

(c) Is there a significant relationship between these attitudes for husbands and wives? Why do you think so?