Test 3

Question 1

What is the purpose of the one-way analysis of variance (ANOVA)? What is the primary advantage of the one-way ANOVA over multiple t-tests?

Answer 1

one way is 3 or more levels and you dont have alpha inflation

Question 2

Define and distinguish between the within-group variability and the between-group variability. What is their relationship to the magnitude of the F ratio?

Answer 2

The between group: Treatment (IV) what we are manipulating, individual differences, and Error.
Within groups: individual differences and error
The f test= between groups when true: is made up of individual differences + error over individual differences & error.
When false:Treatment + individual differences + error/ individual differences + error.
The F ratio increases when the treatment increases.

Question 3

What is the relationship between the total sum of squares, the between group sum of squares, and the within group sum of squares?

Answer 3

The total is when you add the between and within together.

Question 4

When is a post hoc test appropriate?

Answer 4

When we reject the null and it takes the groups and splits it up into pairs. Use this when we’re comparing 3 or more groups. It tells us which specific groups differ.

Question 5

5. What is the underlying assumption of homogeneity of variance?

Answer 5

The populations that are being compared have similar variances.

Question 6

What are the advantages of a factorial ANOVA compared with conducting multiple separate one-way ANOVAs?

Answer 6

This test does it once all in one. Always multiple things that are going on and on can effect. This test always throw multiple things in the pot. Factorial Anova allows to look at interaction.

Question 7

Explain the concept of an interaction

Answer 7

This means the effects of one IV depend on the level of another IV.

Question 8

What are the three possible outcomes of a correlation coefficient computed on two variables? Describe what each means and give an example.

Answer 8

Positive 2 up arrows
negative: one up arrow and one down arrow
0 correlation; no relationship

Question 9

Explain the meaning of the following statement; Correlation does not imply causation.

Answer 9

cant determine with a correlation and can say there related but cant say one causes the other.

Question 10

Define correlation coefficient in words

Answer 10

the sign= direction of relationship

magnitude= strength of variables