Review Questions #5
The below question are based on the following data set. A researcher tested ten young and
ten old subjects on both a memory test (MT) and a vocabulary test (VT). In both cases the
Higher the score the better the performance.
Young
MT VT
23 101
19 95
20 96
25 100
24 115
17 90
18 93
22 104
16 90
21 108
MT
19
20
16
17
14
12
15
11
13
18
Old
VT
115
120
111
115
105
99
102
96
98
110
1. A researcher hypothesized that the young would better on both the memory
and the vocabulary tests. Is there evidence to support her hypotheses?
2. Is there a relation between memory and vocabulary performance?
3. What VT score would you predict for a subject with a MT score of 9?
What restrictions would you place on the prediction?
4. Should the same regression line be used to predict the vocabulary scores from
the memory scores for both the young and the old?
5. Is the strength of the relation between MT and VT different for young and old?
6. Illustrate how you might convert question #2 into a Chi-Squared question.
How do the answers differ and why?