Research methods

Research methods

Hypothesis

• Directional hypotheses - Direction of change
• Non-directional hypotheses - Change with no direction
• Null hypotheses - State no change

Control of variables

• Extraneous variables - Variables other than the IV that may affect the DV
• Confounding variables - An extraneous variable that affected the DV.
• Demand charateristics - When participants change their behaviour after working out the aim
• Investigator effects - Unwanted influence of the investigator that may influence the results
• Randomisation - The use of chance to control the effects of bias 
• Standardisation - Using the same formalised procedures.

Experimental design

• Independent groups - Two seperate groups experience two different conditions
• Repeated measures - All participants take part in all conditions
• Matched pairs - Pairs of participants are matched on some variables that may affect the DV.
• Random allocation - Attempting to control for participant variables in an independent groups design
• Counterbalancing - Attempting to control for the order effects in a repeated measures design

Types of experiment

• Lab - Takes place in a controlled environment/ Control over IV and extraneous variables
• Field - Takes place in a natural setting. Iv is manipulated and DV recorded
• Natural - IV is naturally occuring and records effect on DV
• Quasi - IV is not determined. Strictly not an experiment

Sampling

• Random - All members of target population ahve an equal chance of being selected
• Systematic - Every nth member of the target population is selected
• Stratified - The composition of sample reflects the proportions of people in certain sub-groups within the target population
• Opportunity - Anyone willing and available is selected
• Volunteer - Participants select themselves to participate

Ethical issues

• Informed consent - Participants are made aware of the aims, their rights and what their data will be used for before they take part.
• Protection from harm - Participants should not be placed at any more risk than they would in their daily lives
• Privacy and confidentiality - The right to control information about themselves.

Ways of dealing with ethical issues

• British psychological society has…