Research Methods Flashcards
3 types of experiments
- Laboratory
- Field
- Natural
Whats a laboratory experiment?
Experiment carried out in a highly controlled environment like a lab
Strengths of lab experiment
Highly controlled = control of any extraneous variables to ensure they dont affect the results
Weaknesses of lab experiment
- Tasks in experiments usually dont represent the behavior as we would test it in the real world
- Ptpcps normally are aware theyre taking part in an experiment - they will display demand characteristics - lowers the validity of the results
Demand Characteristics meaning
Ptcps have an interpretation of what they want, they will change their behaviour to match with their interp. of the aims of the study
What are field experiments?
Take place in “the field” - natural environment and researcher still controls the IV to see what effect it has on the DV
Strengths of field exp.
- Ptcps usually are unaware they are taking part in an exp. - more likely to act naturally and not show DC - increases validity as results are more accurate to what would happen irl
Weaknesses of field exp.
- Experimenter has less control over extraneous variables as environment isnt highly controlled - lower validity - lower accuracy
- Ethical issues - deception and informed consent
What is a natural exp.?
Where IV is naturally occuring and researcher has no control over it
Strengths of natural exp.
- They can take place in lab setting
- High ecological validity
- No demand characteristics
Weaknesses of natural exp.
- Events may only take place rarely so its hard for psychologists to follow up their research or for others to do the same - not reliable
- Researcher not able to randomly allocate ptcps to certain coniditons of the IV - results may not be accurate
What is a hypothesis?
Formal and testable statment of the relationship between 2 variables thats tested through experimentation
Whats a null hypothesis?
No relationship/impact
Whats an alternative hypothesis?
A prediction that 1 variable will affect the other
Target Population
Group of indiviuals researcher is interested in. Important because r. needs to gain a representative sample that allow them to make generalisations across the whole pop
4 types of sampling methods
- Random
- Oppurtunity
- Systematic
- Stratified
Whats the random sampling method?
Where every member of the target pop has en equal chance of getting selected
Strengths of random sampling method
- More unbiased - more likely to be more representative of the target pop - makingmore valid generalisaitons possible from research findings
Weaknesses of random sampling method
- Time-consuming as attempting to gather enough willing ptcps from a target pop takes a lot of time and effort
Whats oppurtunity sampling method?
Asking those around and most easily available that represent the tagret pop to ptcp in study
Strengths of oppurtunity sampling method
- Easiest and quickest ways to gather ptcps for a study compared to others
Weaknesses of oppurtunity sampling method
- Possible researcher can influence those selected as process isnt randomised
- Researcher may selecct the ppl they think will support their hypothesis - researcher bias is a potential hinderance
Whats systematic sampling method?
Selecting every “nth” member of the target pop
Strengths of systematic sampling method
- Little risk of researcher bias - reliable results
Weaknesses of systematic sampling method
- You need a bigger sample to filter out ptcps
- Gathering is time consuming
Whats stratified sampling method?
Sub-groups within the target pop are identified
Strengths of stratified sampling method
- Very representative of TP - findings have high reliability and validity to make generalisations to the TP
Weaknesses of stratified sampling method
- Time-consuming to identify sub-groups, select necessary ptcpsand attempt to get a proportionate sample involved in the study
- Extremely difficult to execute and can be impractical
Types of experimental design
- Independant groups
- Repeated measures
- Matched pairs