types of experiments

• What is a lab experiment?

  A study in a controlled, artificial setting
• What is the purpose of manipulating an independent variable in a lab experiment?

  To measure its effect on the dependent variable
• What are extraneous and confounding variables in lab experiments?

  Variables that can affect the outcomes of research
• Why are lab experiments considered the most scientific method of conducting research?

  They allow for control over variables
• What are the strengths of lab experiments?

  • High internal validity due to control of extraneous variables
  • Changes in the dependent variable are due to the independent variable
  • Easily replicable, confirming findings and supporting validity
• What does high internal validity in lab experiments indicate?

  Changes in the dependent variable are due to the independent variable
• Why can lab experiments be easily replicated?

  Greater control means fewer new extraneous variables
• What are the weaknesses of lab experiments?

  • May lack generalizability due to artificial settings
  • Participants may not behave naturally
  • Demand characteristics can influence responses
• What does low external validity in lab experiments imply?

  Findings cannot be generalized to everyday life
• What are demand characteristics in lab experiments?

  Cues that invite specific responses from participants
• How can demand characteristics affect internal validity?

  They may explain findings instead of the IV effect
• What is a field experiment?

  A natural setting where researchers manipulate variables
• How does the researcher interact with participants in a field experiment?

  The researcher goes to the participants
• What is manipulated in a field experiment?

  The independent variable
• What is recorded in a field experiment?

  The effect on the dependent variable
• What are the strengths of field experiments?

  • More natural environment
  • Participants are more comfortable
  • Behavior is more authentic
  • Results may generalize to everyday life
  • Greater external validity due to unaware participants
• Why is a natural environment considered a strength in field experiments?

  Participants behave more authentically and comfortably
• What does greater external validity mean in the context of field experiments?

  Findings can be generalized to real-life situations
• What are the weaknesses of field experiments?

  • Difficult to control confounding variables
  • Changes in dependent variables may not be due to independent variables
  • Harder to establish cause and effect
  • Ethical issues regarding informed consent
• What is a major challenge in controlling variables in field experiments?

  Confounding and extraneous variables are difficult to manage
• Why is it harder to establish cause and effect in field experiments?

  Observed changes may be due to other variables
• What ethical issue is associated with field experiments?

  Participants may not have given informed consent
• How can the lack of informed consent in field experiments be viewed ethically?

  As an invasion of participants' privacy
• What is a natural experiment?

  An experiment without manipulation of the independent variable
• How does the independent variable change in a natural experiment?

  It changes due to external factors, not the experimenter
• What can the dependent variable in a natural experiment be?

  It may be naturally occurring or devised by the experimenter
• What are the strengths of natural experiments?

  • Practical and ethical option for research
  • Greater external validity due to real-world issues
• Why might a natural experiment be the only ethical option for certain studies?

  Because manipulating the independent variable may be unethical
• What does greater external validity in natural experiments imply?

  Findings are more relevant to real experiences
• What is a limitation regarding the frequency of natural events in natural experiments?

  Natural events may occur rarely, limiting research
• How does the lack of random allocation affect natural experiments?

  It may result in confounding variables that reduce validity
• What is the impact of confounding variables in natural experiments?

  They reduce the internal validity of the findings
• What are the weaknesses of natural experiments?

  • Rare occurrence of natural events limits research
  • Lack of random allocation leads to confounding variables
  • Reduces internal validity of the findings
• What is a quasi-experiment?

  An experiment with an independent variable based on existing differences
• How is the independent variable in a quasi-experiment defined?

  It is based on existing differences between people
• What distinguishes a quasi-experiment from a natural experiment regarding the independent variable?

  The independent variable cannot be changed by anyone
• What types of dependent variables can be used in a quasi-experiment?

  They may be naturally occurring or devised by the experimenter
• What are the strengths of quasi-experiments?

  • High control due to controlled conditions
  • Shares strengths of lab experiments
  • Replication is possible
  • Allows comparison between different groups of people
• Why is there often high control in quasi-experiments?

  They are often carried out under controlled conditions
• What does the ability to compare people in a quasi-experiment allow researchers to do?

  Make comparisons between different types of people