T7: Research methods

• What does the experimental method involve?

  The manipulation of an independent variable (IV) to observe its effect on a dependent variable (DV).
• What are the types of experiments mentioned in the experimental method?

  Field, laboratory, quasi, and natural experiments.
• What is the purpose of an aim in research?

  To provide a general statement about what the researcher plans to investigate.
• How are aims developed in research?

  Aims are developed from theories and previous research readings.
• What is a hypothesis?

  A precise statement that clearly states the relationship between the variables being investigated.
• What distinguishes a directional hypothesis from a non-directional hypothesis?

  A directional hypothesis states the direction of the relationship between variables, while a non-directional hypothesis does not.
• Provide an example of a directional hypothesis related to sleep and memory performance.


  "The more sleep a participant has, the better their memory performance."
• Provide an example of a non-directional hypothesis related to sleep and memory performance.


  "The difference in the amount of hours of sleep a participant has will affect their memory performance, shown by differences in memory test scores."

  
• When is a directional hypothesis typically used?

  When previous research suggests a particular outcome related to the study's aim.
• What is the independent variable (IV) in an experiment?

  The aspect of the experiment that is manipulated by the researcher.
• What is the dependent variable (DV) in an experiment?


  The aspect of the study that is measured and is affected by changes in the IV.
• Why is it important to control extraneous variables in an experiment?


  To ensure that any effect on the DV is solely due to the IV.
• What are the two conditions needed to test the effect of the IV?

  The experimental condition and the control condition.
• What does operationalisation of variables mean?

  Clearly defining the variables in terms of how they are measured.
• How can a hypothesis be operationalised in the context of sleep and memory performance?

  "Participants that get at least four hours of sleep will show better performances on the memory test, achieving higher scores than those with less than four hours of sleep."

  
• What is the difference between extraneous variables and confounding variables?

  Extraneous variables affect the DV but do not vary systematically with the IV, while confounding variables change systematically with the IV.
• What is an example of an extraneous variable in a sleep study?

  The lighting in the lab or the age of participants.
• What is an example of a confounding variable in a sleep study?

  The time of day the experimental task is done.
• What are demand characteristics?

  Cues that make participants feel they can guess the aim of the investigation, potentially altering their behavior.
• What is participant reactivity?

  When participants change their behavior due to cues from the researcher or the research situation.
• What is the 'Please-U effect'?

  When participants act in a way they think the researcher wants them to.
• What is the 'screw-U effect'?

  When participants intentionally underperform to sabotage the study's results.
• How do demand characteristics affect the validity of research results?

  They can lead to unnatural behavior, affecting the validity of the results.
• What are investigator effects?

  Unwanted influences from the researcher’s behavior on the DV measured.
• What is randomisation in research?

  The use of chance to reduce the effects of bias from investigator effects.
• What is standardisation in research?

  The use of the same formalised procedures and instructions for every participant.
• What are the strengths and limitations of laboratory experiments?

  Strengths:

  • High degree of control over variables
  • Greater accuracy and replication potential

  
  

  Limitations:

  • Experimenter's bias can affect results
  • Low ecological validity due to artificial settings

  
• What are the strengths and limitations of field experiments?

  Strengths:

  • High ecological validity due to natural settings
  • Controlled IV

  
  

  Limitations:

  • Ethical considerations regarding privacy
  • Loss of control over extraneous variables

  
• What are the strengths and limitations of quasi-experiments?

  Strengths:

  • Controlled conditions enhance replicability
  • Likely to have high internal validity

  
  

  Limitations:

  • Cannot randomly allocate participants
  • Potential confounding variables present

  
• What are the strengths and limitations of natural experiments?

  Strengths:

  • Opportunities for research that would be impossible otherwise
  • High external validity due to real-life issues

  
  

  Limitations:

  • Rare natural events make replication difficult
  • Difficult to randomise participants

  
• What are the different sampling methods in research?

  1. Opportunity sampling

  • Convenient and time-saving
  • Lacks generalisability

  
  

  1. Random sampling

  • No researcher bias
  • Time-consuming

  
  

  1. Systematic sampling

  • Fairly representative
  • Not truly unbiased

  
  

  1. Stratified sampling

  • Produces representative data
  • Time-consuming

  
  

  1. Volunteer sampling

  • Quick access to participants
  • Volunteer bias present

  
• What are the strengths and limitations of independent groups design?

  Strengths:

  • No order effects
  • Less likelihood of demand characteristics

  
  

  Limitations:

  • No control over participant variables
  • Requires more participants

  
• What are the strengths and limitations of repeated measures design?

  Strengths:

  • Eliminates participant variables
  • Fewer participants needed

  
  

  Limitations:

  • Order effects present
  • Boredom may affect performance

  
• What are the strengths and limitations of matched pairs design?

  Strengths:

  • No order effects
  • Less demand characteristics

  
  

  Limitations:

  • Time-consuming and expensive
  • Large pool of participants needed

  
• What is the purpose of a pilot study?

  • To identify potential problems in the study
  • To modify procedures before the main investigation
  • To save time and money in the long run
• What is the difference between single-blind and double-blind procedures?

  Single-blind:

  • Participants do not know if they receive treatment or control.

  
  

  Double-blind:

  • Neither participants nor experimenters know who receives treatment.

  
• What is a pilot study?

  A pilot study is a small-scale version of an investigation conducted before the real investigation.
• Why are pilot studies conducted?

  They are conducted to identify potential problems and modify procedures to save time and money.
• What is a single-blind procedure?

  A single-blind procedure is when researchers do not inform participants if they are receiving a test or control treatment.
• What is the purpose of a single-blind procedure?

  It aims to prevent participants from biasing results by acting in ways they think they should act.