Week 2 - Research Design I

Question 1

What are the 3 key features of the experimental method?

Answer 1

1. MANIPULATING the independent variable
2. CONTROLLING extraneous variables
3. MEASURING the dependent variable

Question 2

What are the following types of independent variable: situational, task, instructional, control?

Answer 2

Manipulating the IV attempts to establish cause-and-effect

(A) Situational: describing/characterising a social situation (eg. number of bystanders in a social study)

(B) Task: the materials/procedure manipulation (eg. divided into groups, then given different difficulties of maths problems)

(C) Instructional: the way we communicate (eg. given the instruction to either memorise using visual imagery OR by no instruction at all)

Question 3

What is the benefit of random participant assignment?

Answer 3

Rules out the possibility there are systematic differences (eg. intelligence, personality, belief in luck etc.) between these two groups

is STRICTLY NON-SYSTEMATIC

Question 4

What is a manipulation check?

Answer 4

Part of the method (eg. a question in a survey) that ensures that the manipulation has had the desired effect on the groups

Question 5

What is sample representativeness?

Answer 5

Correspondence between the sample and the population to which the research is to be generalised on dimensions RELEVANT to the research processes

can research be generalised to other populations in a similar relevant context

Question 6

What is indirect manipulation?

Answer 6

Researcher manipulates a variable that is not the primary variable of interest - but is related to or influences the variable of interest

Question 7

What is an extraneous variable? How is it different to a confounding variable?

Answer 7

Extraneous: Any variable NOT OF IMMEDIATE INTEREST to a researcher which may THREATEN VALIDITY because it compromises the INTERPRETATION OF RESEARCH FINDINGS

Confounding: ACCIDENTAL MANIPULATION of an EXTRANEOUS VARIABLE that occurs because that variable is associated with an IV in an experiment
- It’s effect on the DV ay be mistaken for the effect of the primary IV

Question 8

What may a pilot study help to identify?

Answer 8

Ceiling Effect: If task is too easy - all scores are very high

Floor Effect: If task is too hard - all scores are very low

Question 9

Measuring the DV issues: outline ‘practical restraints’ and ‘relevance-sensitivity trade off’

Answer 9

Practical Restraints: ethical and moral issues (eg. research into drink driving - you can’t give people alcohol and let them drive)

Relevance-Sensitivity Trade Off: the more sensitive a DV is to changes in the IV, the less relevant it may be in the real-world phenomena in which one is interested –> “proxy” measures may not be similar enough to the variable they are attempting to imitate

Question 10

What are quasi experiments?

Answer 10

Differences on the IV already exist -they are NOT manipulated by a researcher (eg. age, gender)
- Cannot be manipulated
- But can select people for each condition based on these characteristics

Question 11

Compare experimental and quasi-experimental studies?

Answer 11

Experimental:
- EVs are controlled for
- Causal Inference can be made
- Can conclude that changes in IV cause changes in DV

Quasi-Experimental:
- EVs cannot be controlled for
- Cannot establish causal inference
- Can only say different groups performed differently