Research Methods

• Research methods in psychology are systematic procedures used to observe, describe, predict, and explain behavior and mental processes
• Research methods


  • Experiments
  • Surveys
  • Case studies
  • Naturalistic observations
• Hypotheses


  Statements about the prediction of the results, that can be verified or disproved by some investigation
• Types of hypotheses


  • Null Hypotheses (H0)
  • Alternative Hypotheses (Ha or H1)
  • One-tailed (directional) hypotheses
  • Two-tailed (non-directional) hypotheses
• Null Hypotheses (H0)


  Predict that no difference will be found in the results between the conditions
• Alternative Hypotheses (Ha or H1)


  Predict that there will be a significant difference in the results between the two conditions
• One-tailed (directional) hypotheses


  State the specific direction the researcher expects the results to move in, e.g. higher, lower, more, less
• Two-tailed (non-directional) hypotheses


  State that a difference will be found between the conditions of the independent variable but does not state the direction of a difference or relationship
• All research has an alternative hypothesis (either a one-tailed or two-tailed) and a corresponding null hypothesis
• Once the research is conducted and results are found, psychologists must accept one hypothesis and reject the other
• Sampling


  The process of selecting a representative group from the population under study
• Sampling techniques


  • Volunteer sample
  • Opportunity sampling
  • Random sampling
  • Systematic sampling
  • Stratified sampling
  • Snowball sampling
  • Quota sampling
• Representative


  The extent to which a sample mirrors a researcher's target population and reflects its characteristics
• Generalisability


  The extent to which their findings can be applied to the larger population of which their sample was a part
• Independent variable


  The one the experimenter manipulates (the thing that changes between the conditions the participants are placed into)
• Dependent variable


  The thing being measured, or the results of the experiment
• Operationalization of variables


  Making them measurable/quantifiable
• Extraneous variables


  All variables which are not independent variable but could affect the results of the experiment
• Demand characteristics


  A type of extraneous variable that occurs if the participants work out the aims of the research study, they may begin to behave in a certain way
• Experimental designs


  • Independent design (between-groups design)
  • Matched participants design
  • Repeated measures design (within groups)
• Counterbalancing


  The best way of preventing order effects from disrupting the findings of an experiment, and involves ensuring that each condition is equally likely to be used first and second by the participants
• Experimental methods


  • Lab Experiments
  • Field experiments
  • Natural experiments
• Case study


  In-depth investigations of a person, group, event, or community, using information from a range of sources
• Correlation


  A measure of the extent to which two variables are related
• Positive correlation


  An increase in one variable tends to be associated with an increase in the other
• Negative correlation


  An increase in one variable tends to be associated with a decrease in the other
• Correlation coefficient


  A value between 0 and 1 that indicates the strength of the relationship between variables
• Correlation does not always prove causation, as a third variable may be involved
• Interview types


  • Structured interviews
  • Unstructured interviews
• Structured interviews


  Formal, with a fixed, predetermined set of questions put to every participant in the same order and in the same way
• Unstructured interviews


  Informal, with no set questions, and the participant can raise whatever topics they feel are relevant
• Questionnaire question types


  • Open questions
  • Closed questions
• Open questions


  Designed to encourage a full, meaningful answer using the subject's own knowledge and feelings
• Closed questions


  Can be answered with a simple "yes" or "no" or specific information, limiting the depth of response
• Interviews


  Most useful in qualitative research to analyze attitudes and values
• Interviews rarely provide a valid basis for generalization
• Main advantage of interviews


  Enable the researcher to probe social actors' subjective point of view
• Questionnaires


  A kind of written interview that can be carried out face to face, by telephone, or post
• Choice of questions in questionnaires

  • Important to avoid bias or ambiguity, 'leading' the respondent or causing offense
• Open question


  • "How do you feel about that situation?"