Extra Exam Knowledge

Question 1

When can you not Interpret r?

Answer 1

If 2 variables are not linear.

Question 2

How Large does the Sample have to be to Ignore the Normality Assumption for an F-Test?

Answer 2

30+ units.

Question 3

How do you Calculate an F Statistic from an ANOVA Table?

Answer 3

Mean square between / mean square within.

Question 4

How do you find an Individual Expected Count?

Answer 4

(Total x axis) x (total y axis) / total of all counts.

Question 5

How do you Calculate Degrees of Freedom?

Answer 5

df = (N rows - 1)(N columns - 1).

Question 6

Do P Values say anything about the Size of Differences?

Answer 6

No.

Question 7

What do we Know about Expected Proportions if the Null Hypothesis is True?

Answer 7

They can be taken from the bottom of the table.

Question 8

What does a Low P Value say about Variability?

Answer 8

Large variability between groups compared to within groups.

Question 9

What is Important to Remember about Differences?

Answer 9

They cannot be practically significant just because they are statistically significant.

Question 10

What can Pilot Surveys not do?

Answer 10

Identify ways of reducing sampling error.