Lecture 8

Question 1

What are the 2 types of manipulations for the repeated measures design and the subcategories?

Answer 1

Increased risk of manipulation awareness: Participant knows what is being manipulated (These are less common in the between subjects design

Demand effect: Ss behaves in way they think experimenter wants

Reactance effect: Ss behaves opposite from what experimenter
wants

(having repeated exposures to the condition can often lead pariticipants to change their behavioru in order to conform to the researchers hypothesis. This is really problematic because the researcher only sees the data that supports the hypothesis. The only way to figure out if you have a demand effect, have a debriefing interview with participants. Ask what they thought the variable was. Ask them to guess about the hypothesis, ask them what they were thinking about when completing the study. )

(best case, the person helping with the research is blind to the hypothesis)

Order effects: Performance may depend on order of conditions, even without manipulation awareness

• Practice effects: Performance improves on later tasks
• Fatigue effect: Performance may decline or inattention may develop later in experiment
  (there are things happening in the human cognitive system that accounts for these effects)
  
  • This is a change in psychological experience!
  • Contrast effect: Participants contrast their response against previous manipulation

Question 2

What is reactance?

Answer 2

Reactance is when the ss tries to mess aroundwith the study, easier to identify then demand

Question 3

Summarize the challenge of repeated measures, provide a solution, and indicate the problem with the solution.

Answer 3

Challenge: Order effects
Psychological experience is confounded with the order of
manipulations

(a naive researchers may ask every participant to try the waters in the same order)
(Will naturally start to tune into the differences )
(emotional experiences form having to drink too much can then translate to the flavour itself)

Example: Taste test for 6 different flavors of seltzer water
- Solution: Counterbalanced design
1. List all possible orders of IV
2. Ss complete one of these orders

(For the fully counterbalaced design, you have to create a list of all the possible orders. Then, participants complete one of the orders. This will create a mixed design meaning one of the variables is manipulated as a repeated measures variable and the other variable is manipulated as a between subjects measure. )

Sounds simple enough but…

• With 6 different experimental treatments, or conditions there are 720 orders!!

(In order for random assignment to be successful we need at least 30 participants for each condition so this may be difficult. )

Question 4

Explain the latin square. advantages? disadvantages?

Answer 4

Each treatment appears once in each ordinal position
Example: Cherry-Lime seltzer appears in position 1,2,3,4,5,6 2. Each treatment appears both before and after unique
treatments
- Example: Cherry-Lime seltzer appears after condition 2, 3, 4, 5, 6

(lets say there is a pickle flavoured seltzer, it could be that whatever comes after the pickle seltzer tastes bad because the pickle flavour is left over. In this case, each of the different flaviours would appear behind the pickle flavour exactly one time)

(BUT, you may miss something like, if you go from lemon, to lime, to sweet etc, may enhance the flavour of the sweet one This is an interactive effect of the two drinks/two flavours. We’re giving up the ability to detect interactive order effects.)

• Advantage: From 720 conditions back to 6
• Disadvantage: Only tests a subset of all possible orders

(The nice part about the latin square is the orders we pick will tell us the most about potential order effects, whats happening at the beginning and end, is there a weird flavour that causes the drink after it to appear less tasty or more tasty etc. )

Question 5

What are mediating variables?

Answer 5

• Mediating variable helps explain the relationship between two other variables
• Mediating variable is changed by IV, and in turn, causes changes in DV

(Every once in awhile we’ll get a fully mediated relationship, meaning the only reason the effect happens is because of the mediated variable. AKA it is only the people who produce a lot of seratonin in response to working out that would experience increased happiness. This is not usually a likely scenario)

Question 6

how is a mediator variable different from a confounding variable?

Answer 6

How is this different from a confounding variable? The mediator is changed in response to the independent variable. Without the independent variable, thre would be no change in the mediator. Contrast this with a confound which is not caused by the IV but instead is a separate/extra indepndent variable that could account for changes in the DV. Basically, it would have its own straght line to the DV that is unrelated to the other IV

Question 6

How do you test for a mediator?

Answer 6

To test for a mediator, we need to have the IV tested, some quantificaiton of the mediator and some quantification of the DV

Question 7

What does studying mediating variables seek to find? Which of the four goals of research is this related to?

Answer 7

Studying mediating variables seeks to explain the relationship between a cause & effect relationship

• explanation

(usually what will happen is the experimenter will demonstrate a cause and effect relationship, they will later start investigating what are the mediators for this relationship? Trying to hypothesize what accounts for the other pathways from exercise to happiness. )

Question 8

Why do we use models in psychology?

Answer 8

We use models to simplify our data, and to make sense of our findings

(we use models to simplify the relationships between variables but the real relationships will be much more complex than what our model suggests)

Question 9

LOOK AT SLIDES 9-12 and WATCH RECORDING