Research methods

Research methods

1. Variables

   • Independent variable (IV)
   • Dependent variable (DV)
   • Confounding variable (CV)
     • Identifying extraneous and potential counfounding variables
       • Individual participant differences
         • age, sex, intelligence, educational background, cultural background
       • Placebo
         • Placebo effect
       • Experimenter effect
         • expectations, bias or actions
       • Order effects
         • Practice effects
         • Carry-over effects
         • Counterbalancing (control or to minimise order effects)
           • Between participants counterbalancing (counterbalancing the order in which the groups are exposed to the experimental conditions
           • Within-participant counterbalancing (Requires each participant to be exposed to the same combination of conditions, in one order and then again in reversed order
   • Extraneous variable (EV)

2. Conditions

   • Experimental condition
     • Experimental group (IV present)
   • Control condition
     • Control group (IV not present)

3. Participant selection and allocation

   • Sampling (selecting participants for a study)
     • Convenience sampling (opportunity sampling) - bias sample
     • Random sampling (every member has equal chance of being selected) - Non-bias
     • Random-stratified sampling (Randomly selecting samples from each stratum)
     • Stratified sampling (Dividing the population into subgroups, or strata)
   • Sample (group of the population that is studied)
   • Population (larger group from which a sample is drawn)

4. Blind procedures

   • Single-blind procedure ( participants is not aware of the condition of experiment they have been allocated to)
   • Double-blind procedure (Participants and researcher directly involved with the participants are unaware of the conditions that participants have been allocated to

5. Participant allocation

   • Experimental group
   • Control group
   • Random allocation (Randomly allocating participants already selected for the study into different groups/ conditions)

6. Standardised instructions and procedures

   • Standardised instructions (instructions given to all participants for each condition are predetermined and identical in terms of how they are given
   • Standardised procedures (Participants are exposed to the same environment and procedures, only exception being the IV. Also techniquesused for making observations and measuring responses should be identical)

7. Research designs

   • Repeated-measures design (each participant is involved in both the experimental and control group)
   • Match-participants design, also called matched-subjects or matched-groups design (selection of pairs of participants that have similar characteristics are allocated to different experimental conditions)
   • Independent-group design, also called between-participants or between subjects design (each participant is randomly allocated to one of the conditions/groups)

8. Types of data

   • Qualitative data (qualities or characteristics), descriptions, words, meanings, pictures
   • Quantitative data (quantities or amounts), measurement or numbers such as raw scores, percentages means and p-value (height or age of a participant)
   • Collecting data
     • Case study (investigation of behaviour or event of interest in an individual, small group or situation)
       • Advantages: -Useful way of obtaining detailed valuable info on mental processes and behaviour. - usually no manipulation or control of variables. - provide a 'snapshot' of the actual real-life experience. - Valuable source of hypotheses for further research.
       • Limitations: - Cannot be replicated to test the reliability of the results. - Cannot be used to test hypotheses
     • Observational study (Watching and recording behaviour as it occurs, includes naturalistic observation, which is naturally occuring behaviour and their presence doesnt influence the behaviour being observed)
       • Advantages: - Record naturally occuring behavious in a real-life setting if naturalistic observation is used, this includes gaining more accurate information
       • Limitations: -Raises ethical concerns of not obtaining informed consent of the participants (participant observation) -Difficult to determine the causees of observed behaviour
     • Self-reports (participants written or spoken responses to questions, statements or instructions, thoughts, feelings or behaviour)
       • Free response (open-ended questions) qualitative data that describes thoughts, feelings or behaviour
       • Fixed-response (closed questions) quantitative data, participants select response from fixed alternative responses (yes, no, rating from 1-10)
       • Advantages: - Useful technique for collecting data on how people think, feel and behave. -Large number of people for a short period of time
       • Limitations: -Rely on assumptions. -May be given deliberately false or misleading answers to create a favourable impression on themselves.

9. Analysing and interpreting data (whether or not the results support or do not support the hypothesis

   • Descriptive statistics (analysing, organising, summarising and describing results, graph or percentage)
     • Measures of central tendency (indicates the central or average value in a set of scores)
       • Mean, Median, Mode
     • Tables, graphs (line graphs, bar charts, histograms, frequency polygons), pie charts
   • Inferential statistics (interpreting and giving meaning to the results, involve mathematical procedures but also involves judgments about results)
     • statistical significance (whether the difference in results obtained is a real difference, not due to chance factors)
       • p-value (significance level of any difference), established before experiment is conducted
     • Conclusions (decision or judgment about what the results obtained mean
     • Generalisations (decision or judgment about how widely the findings or a study can be applied)

10. Participants rights

    • Confidentiality ( right to privacy, any details of involvement in study such as test results or personal information cannot be revealed unless written consent is obtained)
    • Voluntary participation (voluntary consent)
    • Withdrawal rights (must inform participants of the nature of the research, are free to participate or decline, permitted to withdraw from a study at any time)
    • Informed consent procedures
    • Debriefing (clarifying each participants understanding of the research study after it has been conducted)
    • Use of deception (study without fully informing participants of its true purpose before the study. In all cases invloving deception, participants must be debriefed at the conclusion of the study)