Experiments

• Experiments involve a manipulation of variables in order to measure what factors affect behaviour
• there is 4 types of experiments;

  • Lab
  • Natural
  • Field
  • Quasi
• Laboratory experiments include 4 requirements;

  • Manipulated IV
  • Controlled Variables
  • Artificial environment
  • Allocation of participants to groups
• Natural experiments include 4 requirements;

  • Natural IV
  • No controlled variables
  • Natural environment
  • No allocation of participants to groups
• Field experiments include 4 requirements;

  • Manipulated IV
  • Controlled variables
  • Natural environment
  • Allocation of participants to groups
• Quasi experiments include 4 requirements;

  • Natural IV
  • Controlled variables
  • Artificial environment
  • No allocation of participants to groups
• A strength of Lab experiments is high controls as each variable is operationalised meaning, it increases validity
• A weakness of Lab experiments is they are highly artificial so are lower in ecological validity
• A strength of Field experiments is they use standardised procedures meaning they are more reliable
• A weakness of Field experiments is they are lower in controls so is less valid
• Independent variables is the variable that is manipulated by the reseacher
• Dependent variables is variable that is measured
• Operationalising variables means defining the variables in very specific terms
• A hypothesis is a testable statement
• Experimental hypothesis can be one-tailed or two-tailed
• One-tailed hypothesis is directional and will be predictive
• Two-tailed hypothesis is none directional and states that there will be a significance but not in what way
• Null hypothesis suggests there will be no difference and all observable difference is due to chance