Experimental Research Method Flashcards
What are the four types of experimental methods used to carry out research?
- Laboratory experiment
- Field experiment
- Natural experiment
- Quasi experiment
What is a research method?
It is a particular way of studying something in order to discover new information about it or understand it better
Definition of a laboratory experiment
- A controlled environment where extraneous and confounding variables are regulated
- Artificial environment
- Participants go-to researcher
- IV manipulated
Advantages of laboratory experiment
- EVS and CVs can be controlled - the effect of EVs and CVs on DVs can be minimized.
- Cause and effect between IV and DV can be demonstrated (high internal validity)
- Can be easily replicated
- Due to standardised procedure the experiment can be repeated
Disadvantages of a laboratory experiment
- May lack generalisability
- Controlled lab environment may rather be artificial and participants are aware they are being studied
- Behavior may not be ‘natural’ and can’t be generalized to everyday life (low external validity)
- Demand characterostocs
- Cues in an experimental situation that invite a particular response from participants. Results of the experiment may be explained by the cues rather than the effect of IV
What is field experiment?
- Natural setting - real life
- Researcher goes to particpant
- IV is manipulated and effect of DV is recorded
Advantages of field experiment?
- More natural envnirnoment
- Particpants are more comfortable in own envirnoment so results may be more generalisable to everydaylife
- Particpants may be unaware they are studied
- They are more likely to behave as they normally do so findings can be generalised. Study has greater external validity
Disadvantages of a field experiment
- More difficult to control CVs as observed changes in DV may no be due to IV to Cv
- Difficult to establish cause and effect than in the lab
- There are ethical issues
- Participants in field experiment may not give informed consent, this is an invasion of participant’s privacy which raises ethical issues
What is natural experiment?
- Experimentor does not manipulate the IV
- IV would have been more varied if experimentor wasn’t interested
- DV may be naturally occuring (e.g exam results ) or may be measured by experimentor
Advantages of natural experiment
- May be the only ethical option
- Unethical to manipulate the IV e.g studying the effects of insititutionalisation of children. Only way casual research done for such topics
- Greater external validity
- Natural experiments involve real-life issues such as effects of natural disaster and stress level
- Findings are relevant to real-life
- Natural experiments involve real-life issues such as effects of natural disaster and stress level
Disadvantages of natural experiment
- Natural event may occur rarely
- One off event reduces opportunity for research . This may limit scope to generalise findings to other similar situations
- Particpants are not randomly allocated. The experimenter has no control where particpants placed as IV pre-exisitng. Result in CV not controlled
What is quasi-experiment?
IV is based on pre-exisitng difference between people e.g age or gender
No one has manipulated variable it simply exist
DV may natural occur (Exam results) or may be measured by the experimentor
Advantages of quasi-experiment
- High control
- Carried under controlled conditions and therefore shares some strengths of lab experiments so increased confidence to draw conclusions
- Comparisons can be made between people
- Quasi-experiment, IV is difference between people. This means that comparisons between different types of people can be made
Disadvantages of quasi experiments
- Particpants are not randomly allocated
- Experimentor has no control over particpants as IV is pre-existing.Particpant variables may caused the change in Dv acting as CV
- Casual relationships are not demonstrated
- Researcher does not manipulate/control the IV and cannot say certain chain in DV due to IV
Research issues
Investigator effect
This can occur when the researcher unintentionally/unconsciously influences the outcome of the research they are conducting
e.g Age
Gender - gender bias
Non-verbal
Physical