Interpreting Statistics Worksheet
Testing of 20 randomly selected subjects yielded two sets of scores: Verbal IQ and Reading Comprehension.
The table below displays the results and descriptive statistics, as well as frequency distribution charts for each variable and a scatterplot of the correlations between the two variables:
| Subject |
Verbal IQ |
Rdg.Comp. |
| 1 |
90 |
88 |
| 2 |
99 |
97 |
| 3 |
101 |
110 |
| 4 |
115 |
121 |
| 5 |
97 |
98 |
| 6 |
98 |
95 |
| 7 |
92 |
89 |
| 8 |
104 |
109 |
| 9 |
103 |
100 |
| 10 |
117 |
100 |
| 11 |
100 |
96 |
| 12 |
98 |
101 |
| 13 |
96 |
105 |
| 14 |
105 |
105 |
| 15 |
78 |
80 |
| 16 |
121 |
99 |
| 17 |
82 |
75 |
| 18 |
85 |
89 |
| 19 |
81 |
78 |
| 20 |
82 |
86 |
| MEAN |
97 |
96 |
| MEDIAN |
98 |
97 |
| MODE |
98 |
89 |
| STD.DEV. |
11.8 |
11.2 |
| RANGE |
43 |
46 |
| CORREL VERB x RDG |
0.79 |
Please answer the following questions within the appropriate column in the table below:
I. Using the provided data and graphs, describe thefrequency distributionfor the IQ test:
a) What is a typical score for this sample?
b) How variable are the scores?
c) How are the scores distributed?
II. Using the provided data and graphs, describe thefrequency distribution of the reading test scores:
a) What is a typical score for this sample?
b) How variable are the scores?
c) How are the scores distributed?
III. Consider the correlation datagiven the provided data and graph:
a) How are IQ and reading achievement related?
IV.Evaluate the data from a psychological testing perspective:
a) Are these samples good representations of the general population?How do you know?
b) What could you do to make them a more representative sample?
c) How would you interpret the correlation results?
d) What are some ways this knowledge of their relationship could be used?