research methods Flashcards
Explain what is meant by Operationalised hypothesis
-Statement of what the researcher believes to be true
-Clearly defined and measurable
Explain the difference between directional and non-directional hypothesis
Directional: States whether changes are greater or lesser, positive or negative etc.
None-directional: Doesn’t state the direction, just difference or correlation etc.
Explain the difference between Extraneous variables and Confounding variables
Extraneous: ‘Nuisance’ variable that makes it more difficult to detect an effect
Confounding: Changes systematically with the IV so we cannot be sure if any observed change in the DV is due to the CV or IV
What is meant by Investigator effects?
-Any effect of investigators behaviour on outcome of the research (the DV)
What is meant by standardisation?
-Using exactly the same formalised procedures for all ppts in a study
What are Pilot studies?
-Small scale trial run of an investigation to test procedures to see if it needs to be modified
What is meant by single blind and double blind?
Single blind- ppt doesn’t know aims of study so demand characteristics are reduced
Double blind- both ppt and researcher doesn’t know sims of study to reduce demand characteristics and investigator effects
A01 Outline independent groups design
-One group does condition A and second group does condition B
-Ppts randomly allocated to experimental groups
A03 Evaluate independent groups design
1) Strength: No order effects
Ppts only tested once so not bored, controls important CV
2) Strength: Will not guess aim
Ppts only tested once so unlikely to guess aims, behaviour more natural
3) Weakness: Participant variables
Ppts in 2 groups are different acting as EV/CV
Reduces validity
4) Weakness: Less economical
Need twice as many ppts due to repeated measures
More time spent which is expensive
A01 Outline Repeated measures design
-Same ppts take part in all conditions
-Should be counterbalanced to avoid order effects
A03 Evaluate Repeated measures design
1) Strength: Ppt variables
Ppts in both conditions have same characteristics
Controls important CV
2) Strength: Fewer ppts
Half number needed than in independent groups
Less time wasted recruiting ppts
3) Weakness: Order effects
Ppts may do better/worse doing similar task twice, practice fatigue effects
Reduces validity
4) Weakness: Ppts guess sims
Ppts may change behaviour
Reduces validity
A01 Outline Matched pairs design
-2 groups of ppts used and pairs based on ppt variables that matter for experiment
A03 Evaluate Matched pairs design
1) Strength: Ppt variables
Ppts matched on relevant variable
Controls ppt variables, enhances validity
2) Strength: No order effects
Ppts only tested once so no practice fatigue effects
Enhances validity
3) Weakness: Matching is not perfect
Time consuming and can’t control all variables
Doesn’t address ppt variables
4) More ppts
Need twice as many ppts because repeated measures
Time spent recruiting which is expensive
A01 Explain what is meant by Laboratory experiment
-Controlled environment
-EV and CVs regulated
-IV is manipulated and effect on DV is recorded
A03 Evaluate Laboratory experiment
1) Strength: EVs/CVs controlled
Effect on DV can be minimised
Cause and effect between IV and DV is demonstrated (high internal validity)
2) Strength: Easily replicated
Control means less chance that new EVs introduced
Findings confirmed supporting validity
3) Weakness: Lack generalisability
May be artificial and ppts aware they’re being studied
low external validity
4) Weakness: Demand characteristics
Cues that invite a particular response from ppts
Findings may be explained by cues rather than effect of IV ( low internal validity)
