LAB - Correlation
Let's assume that we want to look at the relationship between two variables, height (in inches) and self-esteem. Perhaps we have a hypothesis that how tall you are affects your self esteem. Let's say we collect some information on twenty individuals (all male -- we know that the average height differs for males and females so, to keep this example simple we'll just use males). Height is measured in inches. Self esteem is measured based on the average of 10 1-to-5 rating items (where higher scores mean higher self esteem). Here are the data for the 20 cases.
|
Person
|
Height
|
Self Esteem
|
|
1
|
68
|
4.1
|
|
2
|
71
|
4.6
|
|
3
|
62
|
3.8
|
|
4
|
75
|
4.4
|
|
5
|
58
|
3.2
|
|
6
|
60
|
3.1
|
|
7
|
67
|
3.8
|
|
8
|
68
|
4.1
|
|
9
|
71
|
4.3
|
|
10
|
69
|
3.7
|
|
11
|
68
|
3.5
|
|
12
|
67
|
3.2
|
|
13
|
63
|
3.7
|
|
14
|
62
|
3.3
|
|
15
|
60
|
3.4
|
|
16
|
63
|
4.0
|
|
17
|
65
|
4.1
|
|
18
|
67
|
3.8
|
|
19
|
63
|
3.4
|
|
20
|
61
|
3.6
|
Using the data provided above, calculate the correlation between height and a measure of self-esteem. You can calculate the correlation either by using the on-line calculator provided or by using Excel. Once you have calculated the correlation do the following:
1. Provide the correlation between height and self-esteem for this sample.
2. Determine whether or not the correlation is significant. If the correlation is significant, indicate the level of significance (the p level).
3. Using the information provided in the lecture, indicate strength of the correlation.
4. What can you say about the relationship between height and self-esteem based on the calculated correlation?
5. What can't you say about the relationship between height and self-esteem?