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 in the experimental method?

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

  A general statement made by the researcher about what they plan to investigate.
• How are aims developed in research?

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

  A precise statement that clearly states the relationship between the variables being investigated.
• What are the two types of hypotheses?

  Directional and non-directional hypotheses.
• What does a directional hypothesis indicate?

  It states the direction of the relationship between the variables.
• What is a non-directional hypothesis?


  A hypothesis that does not specify the direction of the relationship between the variables.
• Give 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."

  
• When is a directional hypothesis typically used?

  When there is previous research suggesting a particular outcome.
• 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 the IV.
• Why is it important to control extraneous variables in an experiment?


  To ensure that the 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."
• What are extraneous variables?

  Variables that are not the IV but may affect the DV.
• What are confounding variables?

  Variables that change systematically with the IV and affect the DV.
• Give an example of a confounding variable in a sleep study.

  The time of day the memory test is conducted.
• What are demand characteristics?

  Cues that make participants feel they can guess the aim of the investigation.
• What is participant reactivity?

  When participants change their behavior due to cues from the researcher or 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 research validity?

  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 bias from investigator effects.
• What is standardisation in research?

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

  Strengths:

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

  
  

  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:

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

  
  

  Limitations:

  • Rare natural events may not be replicable
  • Difficult to randomise participants

  
• What is the population in research?


  The group of people from whom the sample is drawn.
• What are the strengths and limitations of opportunity sampling?

  Strengths:

  • Easy and time-saving recruitment
  • Less costly

  
  

  Limitations:

  • Not representative of the whole population
  • Researcher bias may be present

  
• What are the strengths and limitations of random sampling?

  Strengths:

  • No researcher bias
  • Equal chances for all members of the population

  
  

  Limitations:

  • Time-consuming to create a sampling frame
  • Volunteer bias may occur

  
• What are the strengths and limitations of systematic sampling?

  Strengths:

  • Avoids researcher bias
  • Usually fairly representative of the population

  
  

  Limitations:

  • Not truly unbiased unless using random number generator

  
• What are the strengths and limitations of stratified sampling?

  Strengths:

  • No researcher bias
  • Produces representative data

  
  

  Limitations:

  • Time-consuming to identify strata
  • Complete representation of the target population is not possible

  
• What are the strengths and limitations of volunteer sampling?

  Strengths:

  • Quick access to willing participants
  • Participants are likely to cooperate

  
  

  Limitations:

  • Volunteer bias affects generalisability
  • Motivations like money may influence results

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

  Strengths:

  • No order effects
  • Less likely for participants to guess aims

  
  

  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 may occur
  • Boredom may affect performance