Booklet 1 Flashcards
Experimental Methods
Independent variable
The variable manipulated by the researcher to monitor the impact on the dependent variable
Dependent variable
The variable measured by the researcher
Ecological validity
The extent to which the results can be applied to real life
Demand characteristics
Participants change their behaviour to present themselves in a good way or because they have guessed the aim of the research
Internal validity
The extent to which we can testify the IV has affected the DV due to a high level of control
Reliability
The consistency of a measure/finding by replicating the research and finding the same results
Validity
How far a test measures what it has set out to measure
Extraneous variables
Variables other than the IV that may affect the DV
Name the experimental methods of research
Natural
Field
Laboratory
Quasi
Name the non experimental methods of research
Observation
Content analysis
Case study
Correlation
Describe laboratory experiments
Highly controlled- researcher has full control over where and how the research is conducted and who its conducted on
Researcher directly manipulates IV and precisely measures DV
Possible to randomly allocate participants to conditions to reduce participant variables
Describe field experiments
Researcher still attempts to hold all variables constant while isolating and manipulating the IV and measuring the effect on the DV
Still possible to randomly allocate participants
Research conducted in a natural environment
Describe natural experiments
Conducted in a participants natural environment
Independent variable is naturally occurring- outside of researcher’s control
Researcher unable to control extraneous variables or randomly allocate participants
Researcher just measures change in dependent variable
Describe quasi experiments
IV is within the person eg gender, personality type, age therefore not manipulated by researcher
Naturally occurring but concerning a person
Impossible to randomly allocate participants to conditions
Describe 2 strengths of laboratory experiments
High internal validity- researcher has high degree of control over extraneous variables and isolates independent variable to allow direct manipulation therefore the change in DV likely to be a result of change in IV establishing cause and effect
Highly replicable- researcher has high degree of control so experiment can be repeated and same results can be found again, results can be assessed for accuracy
Describe 2 weaknesses of laboratory experiments
Low ecological validity- artificial settings with artificial tasks so may not represent behaviour in real world
May be influenced by demand characteristics- participants are aware they’re being studied so may change behaviour, reducing validity of results
Describe 2 strengths of field experiments
Fair degree of internal validity- researcher attempts to control extraneous variables so change in DV likely due to change in IV so can establish cause and effect
Less likely to be affected by demand characteristics- familiar environment so participants behave more naturally
Give 2 weaknesses of field experiments
Ethical issues- participants may be unaware they’re part of an experiment so unable to give informed consent
Lower internal validity- harder to control extraneous variables so hard to establish causality
Give 2 strengths of natural experiments
High ecological validity- natural setting where IV occurs naturally so participants less likely to show demand characteristics
Useful to investigate concepts that would be unethical to directly manipulate- IV occurs naturally so researcher isn’t directly subjecting participants to harm
Give 2 weaknesses of natural experiments
Low internal validity- researcher has little control over extraneous variables so can’t be certain change in DV is due to IV
May be unethical- participants may not know they are taking part so cannot give informed consent
Name 5 ways of controlling extraneous variables
Carry out a pilot study to highlight potential EVs
Standardised procedure, task, environment, instructions etc
How do you structure a consent form?
Dear prospective participants
Aim of research
Details of task
Give right to withdraw
State results will be confidential and stored securely
Sign below if you agree
Sign:_____ Date:_____
What is a confounding variable?
Something that varies systematically with the IV that may act as a second IV
Describe investigator effects.
A researcher’s expectation may influence how the study is designed (which may influence a certain group)
Researcher’s behaviour may be different towards different groups (encouraging tone of voice, facial expressions etc) which may lead to demand characteristics
Expectations may affect how the researcher takes measurements ie being more generous for one group
