Types of Experiments

• An Aim is a general statement of what the researcher intends to investigate as the purpose of the study
• A Hypothesis is a clear, precise, and testable statement that predicts the relationship between the independent & dependent variables
• Laboratory experiments are conducted in highly controlled environments
• Laboratory experiments have high control over confounding & extraneous variables so have high internal validity and are replicable
• Laboratory experiments lack generalisability as the environment is artificial so have low external validity & mundane realism, and may show demand characteristics
• Field experiments are conducted in a natural, more everyday setting which is a usual environment for the participant
• Field experiments have high mundane realism so show more authentic behaviour
• Field experiments are difficult to control for confounding & extraneous variables
• Field experiments may have ethical issues if participants have not consented to being studied
• Natural experiments are when the researcher has no control over the independent variable
• Natural experiments have high external validity as they study real-world issues
• Natural experiments are limited as there are rarely opportunities for research and the relationships between independent & dependent variables may be unsure
• Quasi experiments are when the indenpendent variable is based on an existing difference between participants
• Quasi experiments are often carried out under controlled conditions so are easily replicated
• Quasi experiments often have confounding variables as participants cannot be randomly allocated
• Pilot studies are small-scale 'trial runs' used to assess the validity and feasibility of the research
• Pilot studies may look at stimuli, timing, instructions