experimental method

• What is the aim in research?

  A general expression of what the researcher intends to investigate
• What is an operationalised hypothesis?

  A statement that is clearly defined and measurable
• What does a directional hypothesis indicate?

  It states whether changes are greater or lesser
• When is a directional hypothesis used?

  When the theory suggests a direction
• What is a non-directional hypothesis?

  It states that there is a difference or correlation without specifying a direction
• When is a non-directional hypothesis typically used?

  When there is no theory or previous research
• What is an independent variable?

  A variable that stands alone and isn't changed by other variables
• What is a dependent variable?

  The variable that the researcher measures
• What is a control variable?

  An element that is not changed throughout an experiment
• Why are control variables important in an experiment?

  They allow better understanding of the relationship between other variables
• research issues:

  extraneous variables -  any variable that you're not investigating that can potentially affect the outcomes of your research study

  confounding variables - those that affect other variables in a way that produces spurious or distorted associations between two variables
• What do demand characteristics refer to in research?

  Any cue from the researcher or research situation that may reveal the aim of the study
• How can demand characteristics affect participants' behavior?

  They can change the participants' behavior based on their understanding of the study's aim
• What is the investigator effect?

  Any effect of the investigator's behavior on the outcome of the research
• What is the purpose of randomisation in research design?

  To control for the effects of bias using chance
• What does standardisation mean in a research study?

  Using exactly the same formalised procedures for all participants
• What is the purpose of pilot studies?

  To conduct a small-scale trial run of an investigation to modify research design
• What is the role of control groups in research?

  To act as a baseline for comparisons and help establish causation
• What is the difference between control groups and control conditions?

  A control group is an independent group design, while control conditions refer to repeated measures design
• What does single blind mean in a research study?

  A participant doesn't know the aims of the study
• How does double blind design help in research?

  It reduces demand characteristics and investigator effect by keeping both participant and researcher unaware of the study's aims
• What is the independent groups design in research?

  One group does condition A and a second group does condition B
• What is an advantage of independent groups design?

  No order effect since participants are only tested once
• What is a disadvantage of independent groups design?

  Participant variables may reduce the validity of the study
• What is the repeated measures design in research?

  Same participants take part in all conditions of an experiment
• What is an advantage of repeated measures design?

  Participant variables are controlled since the same participants are used
• What is a disadvantage of repeated measures design?

  Order effects can reduce the validity of the results
• What are matched pairs in research design?

  Two groups of participants are paired based on relevant participant variables
• What is an advantage of matched pairs design?

  Participant variables are controlled by matching on relevant variables
• What is a disadvantage of matched pairs design?

  Matching is time-consuming and may not control all relevant variables
• Why is matched pairs design more expensive?

  It requires twice as many participants as repeated measures for the same data
• What are the advantages and disadvantages of independent groups design?

  Advantages:

  • No order effect
  • Participants are unlikely to guess the aim

  
  

  Disadvantages:

  • Participant variables may reduce validity
  • More participants needed than repeated measures
• What are the advantages and disadvantages of repeated measures design?

  Advantages:

  • Controls participant variables
  • Fewer participants needed

  
  

  Disadvantages:

  • Order effects can reduce validity
  • Participants may guess the aims
• What are the advantages and disadvantages of matched pairs design?

  Advantages:

  • Controls participant variables
  • No order effect

  
  

  Disadvantages:

  • Matching is time-consuming
  • More participants needed than repeated measures