In an extensive study involving British children, Arden and Plomin (2006) found significantly higher variance in the intelligence scores for males than females. Below are intelligence scores for a group of male children.

DATA SET A: 9, 11, 10, 13, 8, 9, 11, 9

Please answer the following question using the above data set. Must show work for credit.

1. Calculate , N

2. Calculate the Mean and Range

3. What are the deviation scores for 12 and 4?

4. What is the standard deviation and variance?

5. What is the predicted population standard deviation and variance using this sample scores?

6. Draw and superimpose a bell curve and label your data up to 3 standard deviation units from the mean. Use the standard deviation from question 4

7. Is the above data set (Data Set A) more or less variable than a data set that has a standard deviation of 2.25? Why (use statistics to support your answer)?

8. Is the above data set (Data Set A) more or less variable than this set: 5, 10, 11, 5, 6, 3, 9, 7 and why (use statistics to support your answer)?