2.7 research methods Flashcards
Name the 4 types of experiments.
- Lab
- Field
- Quasi
- Natural
What is a laboratory experiment?
conducted in a controlled environment (set up by the researcher = artificial setting)
researcher directly manipulates IV
standardised procedures
random allocation of ppts
measures a DV
What is a field experiment?
conducted in a real world setting (realistic environment)
researcher directly manipulates IV
confederates
What is a quasi experiment?
researcher has no control over the IV as it’s a characteristic of the individual (e.g. age or gender) ~ naturally occurring
researcher can put a task in place to measure DV
some control over EVs
What is a natural experiment?
researcher has no control over the IV (naturally occurring) e.g. studying the effects of covid on language development
DV is therefore also naturally occurring
little control over EVs
Evaluate lab experiments.
+ high in reliability as they use standardised procedures and take place in highly controlled settings where EVs are limited
- low in ecological validity as settings are artificial so behaviour = less likely to represent everyday life
Evaluate field experiments.
+ low in reliability as real-life settings are unpredictable
- high in ecological validity as take place in a real-life setting
Evaluate quasi experiments.
+ depends whether conducted in lab or field
- low in internal validity as random allocation of ppts is not possible bc IV is a characteristic so ppt variables may confound results
Evaluate natural experiments.
+ very high in ecological validity
- low in internal validity as researcher has no control over environment, EVs (later become confounding)
- natural events are rare
What is a research aim?
identifies the purpose of the investigation
a straightforward expression of what the researcher is trying to find out
What is a hypothesis?
an operationalised hypothesis = precise, testable statement about the expected outcome of a piece of research
two types:
1. null
2. alternate
hypotheses must:
be a predictive statement
refer to all conditions of the IV
refer to the operationalised DV
What is a null hypothesis?
researcher will not find any results of statistical significance
“There will be no significant difference between… and any difference will be due to chance.”
What are the two types of alternate hypotheses?
- non-directional
- directional
What is a non-directional hypothesis?
when researcher is unsure of likely outcome
“there will be a significant difference between…”
What is a directional hypothesis?
researcher has a good idea of what results are likely to be in a study (based on previous research)
Define target population.
large group of people that u want to study
findings and conclusions are generalised to this group
Define sample
smaller group from target population that have been selected to participate in the study
Name all the sampling techniques.
- volunteer
- systematic
- opportunity
- stratified
- random
Describe and evaluate
