Interpreting Statistics Worksheet
PSY 335 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 the frequency distribution for the IQ test: a) What is a typical score for this sample? b) How variable are the scores? c) How are the scores distributed?
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| II. Using the provided data and graphs, describe the frequency 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?
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| III. Consider the correlation data given the provided data and graph: a) How are IQ and reading achievement related?
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| 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?
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Reading Comprehension Frequency Distribution
Frequency 70 80 90 100 110 120 More 0 3 4 7 6 1 0
STD SCORE
Verbal IQ Frequency Distribution
Frequency 70 80 90 100 110 120 More 0 1 4 7 4 2 1
STD SCORE
Frequency
Rdg.Compre 90 99 101 115 97 98 92 104 103 117 100 98 96 105 78 121 82 85 81 82 88 97 110 121 98 95 89 109 100 100 96 101 105 105 80 99 75 89 78 86
Verbal IQ Score
Reading Scores
