Chapter 10 Practice Questions

Question 1

What is systematic between group variance?

Answer 1

Systematic between groups variance reflects consistient group differences due to independent variable, uncontrolled confounding variable or both.

Question 2

Define experimental variance

Answer 2

Experimental variance is due to the effect of the independent variable.

Question 3

What is error variance?

Answer 3

Error variance is the nonsystematic within groups variability that is due to random factors that affect some participants more than others or to individual differences.

Question 4

What is f test?

Answer 4

The F test is an inferential statistical procedure.

Question 5

What is f test used for?

Answer 5

The f test tests for group differences.

Question 6

What are the ways of controlling extraneous variance?

Answer 6

They are controlled by making sure that the experimental and the controlled groups are as similar as possible and treating all the same way except for the independent variable manipulation.

Question 7

Define extravenous variable?

Answer 7

Extraneous variance is due to the effects of uncontrolled confounding variables.

Question 8

How can error variance be minimized?

Answer 8

It can be minimised through careful measurement and/or using a correlated groups design to control individual differences.

Question 9

Of these four non experiemental what is the weakest and why?

Answer 9

The weakest design is the ex post factor design which controls virtually none of the potential confounding variable.

Question 10

When is maturation not considered a confounding variable?

Answer 10

Maturation is not considered a confounding variable in studies of development.

Question 11

What type of design do researchers use to study maturational processes?

Answer 11

Development studies typically employ time series designs.

Question 12

What is the most basic experimental design?

Answer 12

Randomised, post test only control group design.

Question 13

What do control groups control for?

Answer 13

History, maturation and regression to the mean.

Question 14

Control groups are effective only if…

Answer 14

Participants are randomly assigned to groups to assure that the groups are comparable at the beginning of the study and they are treated exactly the same during the study except for the independent variable manipulation.

Question 15

What does the Solmon four group design control for?

Answer 15

The Solmon four group design controls for the possible interaction of the pretest and treatment.

Question 16

What could happen if groups are not equivalent at the beginning of the study?

Answer 16

Observed differences could be due to the manipulation, the initial differences, or both.

Question 17

When is ANOVA used?

Answer 17

ANOVA is used when two or more groups are compared on a dependent measure that produces score data.

Question 18

What does the ANOVA summary table show ?

Answer 18

The ANOVA summary table shows the sources of variance, the degree of freedom for each source of variance, the sum of squares, the mean squares, the F ratios and the probability values for each F.

Question 19

Why is the f ratio significant?

Answer 19

When at least one mean is significantly different from at least one other mean.

Question 20

Would it be unethical for researchers to randomly assign participants that expose them to risk?

Answer 20

Yes.

Question 21

What is the most important safeguard in research?

Answer 21

Informed consent.