Lab & Field Experiments

• Lab experiment: A controlled experiment that is conducted in a lab setting, where variables are manipulated to uncover a cause and effect relationship.


  Positivists prefer lab experiments because their main goal is reliability, lab experiments are easily replicated and standardised & also allows them to identify the cause and effect.
• • Independent variable: the variable that is being altered (e.g, gender, temperature or light).
  • Dependent variable: the variable that is measured, it is dependent on the IV (e.g. a plant's growth and peoples reactions).


  Extraneous variables: undesirable factors that may affect the dependent variable, for example temp, lighting, noise, time and participant's mood.
• Lab experiment example: Stanley Milgram 1961 


  Milgram's methodology: A fake shock generator, 40 male participants, volunteer sample to take part in an experiment on 'memory & learning', testing how far people would obey orders, 'learner' was an actor and the 'teacher' was a respondent, teacher asked questions & wrong answers were punished by an electric shock, punishable up to 450 volts.
• Milgram's conclusions:

  2/3 went all the way to 250 volts when a learner said he had heart trouble and was in pain

  • The study demonstrates power of the social situation over the individual and that we should do as we are told
  • He conducted 19 more of the same experiments and managed to achieve a conformity of 90%
  • The experiment method allowed people's reactions to be truly tested even though it was highly unethical.
• Positivists prefer using lab experiments because they ensure reliability and it is a standardised procedure. However interpretivists reject them as they don't allow them to build a relationship with their respondents.
• PET advantages of Lab experiments:

  • Practical: can manipulate variables to suit researcher & easy to access willing participants (volunteer sampling)
  • Ethical: no risk of harm to the researcher, consent can be gained & agreed by an ethics board.
  • Theoretical: easy to generalise data, able to repeat as it is reliable, standardised procedure & positivists approve it and are most likely to choose this method.
• PET disadvantages of Lab experiments:

  • Practical: costly as you need to acquire a venue & cant completely eliminate extraneous variables.
  • Ethical: cant gain INFORMED consent, risk of harm to the participants & wont have the right to withdraw sometimes.
  • Theoretical: lacks verstehen, lacking validity as a lab is an artificial environment.
• Field experiments: When variables are manipulated to uncover cause and effect relationships in a natural setting in the social world (e.g. work, school, shops)


  Interpretivists approve this method as it allows them to gain verstehen and build a relationship between their respondents.
• Field experiment example: Black and White Room for the night

  • Background: An experiment to test the extent of racism in a typical British town, Bristol was chosen as it has the same proportion of ethnic minorities as Britain as a whole.
  • Methodology: The experiment was covert, used hidden cameras and acted natural as possible. The IV: skin colour (Tim was white & Geoff was black), the DV: people's reactions.
  • Conclusions: 2/3 of the people they had approached had treated them in the same way but 1/3 had discriminated against Geoff (e.g. charged him more for bed and breakfast).
• PET advantages of Field experiments:

  • Practical: cheap as you don't have to pay volunteers, easy to access respondents who are there (opportunity sampling) & quick and efficient.
  • Ethical: it is anonymous & can be ethically justified.
  • Theoretical: no Hawthorne effect increasing the validity, participants are reacting naturally, quantitative data.
• PET disadvantages of Field experiments:

  • Practical: permission may be required for some social settings & is time consuming to plan.
  • Ethical: lacks consent, no option to withdraw & can cause harm & distress to researcher and participant.
  • Theoretical: uncontrollable factors (extraneous) which reduces validity, often too small scale to be representative enough to make wider generalisations.