L3 - Variance, effects and experiment design

Question 1

What is construct validity?

Answer 1

How accurately your measures asses what they are supposed to (you would have “poor” or “good” construct validity).

Question 2

What is treatment variance?

Answer 2

Variance from the mean for each of our different conditions.

Question 3

What is a confounding variable?

Answer 3

An extra variable that can (like the IV) have an effect on the DV and therefore mask or skew the results.

Question 4

What is error variance?

Answer 4

Difference in results due to other variables/factors influencing the participants that the researcher does not examine (caused by confounding and extraneous variables).

Question 5

what is the ‘Ceiling effect’?

Answer 5

The task is too easy meaning that all participants results are clustered around the “best” possible score.

Question 6

what is ‘floor effect’?

Answer 6

The task is too hard meaning all the participants results are clustered around the “worst” possible score.

Question 7

What are order effects?

Answer 7

When the order in which the task is presented to the participant affects the results.

Question 8

What are history effects?

Answer 8

Events that happen in the environment that change the conditions of a study, affecting its outcome.

Question 9

What are maturation effects?

Answer 9

Any biological or psychological process within an individual that systematically varies over time, independent of specific external events e.g. hunger, aging, mood.

Question 10

What are testing effects?

Answer 10

When scores on the post-test are influenced by simple exposure to the pre-test (when prior observation affects later observation).

Question 11

What are practice effects?

Answer 11

When the repetition of a task means the participant improves due to this and can then effect results.

Question 12

What are fatigue effects?

Answer 12

When participants get bored/tired during an experiment which impacts the effort they put in and can subsequently impact the results.

Question 13

What is a pretest-posttest design?

Answer 13

Where the participants are studied before the the IV is manipulated and again observed after the intervention.

Question 14

What are demand characteristics?

Answer 14

Cues that might indicate to a participant the true purpose of the study.

Question 15

What are 2 of the ways you can rule out/minimise order effects?

Answer 15

Counterbalancing and the Latin-square design.

Question 16

What is counterbalancing?

Answer 16

When you have half of the participants complete a task in one order and the other half in a different order.

Question 17

What is the Latin-square design?

Answer 17

When you have 4 different orders participants complete the tasks in, this is determined by a 4x4 column and row data set.

Question 18

What is a matched design?

Answer 18

Assigning participants to different groups within the experiment based on specific variables that are significant to the test e.g. age, gender etc.

Question 19

What is a passive control group?

Answer 19

The group of participants that don’t partake in anything or are made to do meaningless tasks.

Question 20

What is an active control group?

Answer 20

A group of participants who could reasonably assume they’re doing something relevant to the experiment.

Question 21

What is attrition?

Answer 21

the dropout rate of an experiment.