research methods

• Aims


  A precise statement of why a study is taking place
• Independent variable


  The one that the experimenter manipulates / changes or naturally changes. The different variations of the IV are called the conditions of the experiment
• Dependent Variable


  The variable that the experimenter measures to see whether the IV had any effect on it
• Operationalising variables


  Making a variable clear, precise and unambiguous. It is the process of devising a way of manipulating or measuring something so that another person knows what has been done
• Operationalisation


  • Can be applied to independent variables, dependent variable of co-variables (in a correlation) and describes how a variable has been clearly defined by the researcher. This is important for Replication
• Extraneous variables


  Any variable other than the IV which could affect the DV
• Confounding variables


  Uncontrolled extraneous variables that mean firm conclusions can't be drawn about cause and effect
• Possible extraneous variables/controls


  • Situational variables
  • Participant variables
• Situational variables


  • Variables connected with the research situation, e.g. time of day, location, materials given to participants
• Participant variables


  • Variables connected with the research participants, e.g. age, gender, intelligence, profession
• Possible controls for extraneous variables


  • Standardisation
  • Counter-balancing
  • Considering experimental design
  • Random allocation
• Demand characteristics


  When participants change their behaviour as a result of the perceived demands of the study
• Demand characteristics


  • Participants may worry about being in a psychological study and want to appear 'normal'
  • They may deliberately try to behave in an unexpected way, this is called the screw-you effect
• Investigator effects


  When researchers can (unconsciously or consciously) influence the results of a study
• Investigator effects


  • Physical characteristics of investigators may influence results, such as age or ethnicity
  • Researcher bias - Investigators may be unconsciously biased in their interpretation of data and find what they expect to find
• Possible controls for demand characteristics and investigator effects


  • Single-blind procedure
  • Deception
  • Randomisation
  • Double blind
  • Inter-rater reliability
• Hypothesis


  A testable statement regarding the expected results of a study
• Types of hypotheses


  • Alternative hypothesis
  • Null hypothesis
• Directional (one-tailed) hypothesis


  Predicts the expected direction of the results
• Non-directional (two-tailed) hypothesis


  Predicts there will be an effect, but doesn't predict the direction of the results
• Experimental methods


  • Laboratory experiments
  • Field experiments
  • Natural experiments
  • Quasi experiments
• Laboratory experiments


  • Take place under controlled conditions in an artificial environment
  • The IV is manipulated (changed). The effect on the DV is measured
• Field experiments


  • Take place in the participants' natural environment
  • The IV is manipulated. The effect on the DV is measured
• Natural experiments


  • The IV is not manipulated, it changes naturally
  • The effect on the DV is measured
• Quasi experiments


  • The IV varies due to being a characteristic of the participants (age, gender etc). It cannot be manipulated
• Experimental designs


  • Independent groups
  • Repeated measures
  • Matched pairs
• Independent groups


  • Testing different groups of people for each condition of the experiment. Participants are randomly allocated and take part in one condition only
• Repeated measures


  • Testing the same group of people for each condition – the same people are used repeatedly. Participants take part in more than one condition
• Matched pairs


  • Participants take part in one condition of the IV but are matched on a relevant variable to someone in the other condition and their data is 'paired'
• Correlation


  Looks at the relationship between two variables. Correlations measure the strength and direction of relationships between co-variables and are plotted onto a scatter-gram
• Types of correlations


  • Positive correlation
  • Negative correlation
  • No correlation
• Correlation coefficient


  The type of correlation will be indicated by the + / - sign. The strength of the correlation is indicated by the value. The closer to '0' the weaker the correlation. The closer to '1' the stronger the correlation
• Correlational hypotheses


  • Directional
  • Non-directional
  • Null
• Observation techniques


  • Controlled observation
  • Naturalistic observation
  • Overt observation
  • Covert observation
  • Participant observation
  • Non-participant observation
• Controlled observation


  • Take place in an artificial laboratory setting. The researcher manipulates some aspect of the environment
• Naturalistic observation


  • Take place in a real life, natural environment where no manipulation is made and everything has been left as it is normally
• Overt observation


  • The participants know their behaviour is being watched and recorded and for what purpose
• Covert observation


  • The participants are not aware they are being observed. The observer may have a hidden viewpoint or be behind a two-way mirror
• Participant observation


  • The researchers become part of the group or situation being observed
• Non-participant observation


  • The researchers do not become actively involved in the behaviour being studied and observe from a distance