types of experiment

• Lab experiment- an experiment carried out in a highly controlled setting 
• • strengths and limitations
  • artificial and contrived
  • low ecological validity 
  • high interval validity - control variables ,establish cause and effect
  • easily replicated
  • demand characteristics- aware behaviour is being studied
• Field

  • a controlled study carried outside a lab (still manipulating IV)
• • high ecological validity (likely to not be aware of being studied) (less demand characteristics)
  • less internal validity - not all variables can be controlled
  • deception if not aware
  • more time consuming and expensive
• natural

  • a research method in which the researcher has not directly manipulated the iv
  • Iv would vary naturally whether the researcher was interested or not   
  • for ethical and practical reasons you can’t manipulate it  
• strength limitations natural +quasi

  • Lack of control over IV = difficult to make causal conclusions as there could be confounding variables
  • Random allocation isn’t possible meaning participants variables may differ over the two groups which could act as extraneous or confounding variables
• strength quasi natural

  quasi - allows comparisons between types of people

  natural - enables psychologists to study 'real' problems, ecological validity-generalisable
• Quasi 

  Iv doesn’t vary its just a set difference between people a condition which already exists