1. Northern Advanced Research Training Initiative Experimental Research Methods Nikos Bozionelos PhD e-mail: nikos.bozionelos@durham.ac.uk

2. Experimental Research

3. Steps in Research Design Implementation (e.g., data collection) Analysis Results valid?

4. Validity: the extent to which the explanation that is indicated by the findings is exclusive and sufficient (i.e.,whether alternative explanations can be ruled out) extraneous factors (i.e., factors outside the scope of the study) may be responsible for the results

5. Validity: the extent to which the explanation that is indicated by the findings is exclusive and sufficient (i.e.,whether alternative explanations can be ruled out) extraneous factors (i.e., factors outside the scope of the study) may be responsible for the results confounding

6. history instrumentation (measures) attrition (“mortality”) maturation causality control for confounding to improve validity

7. confounding history instrumentation (measures) attrition (“mortality”) maturation causality control for confounding to improve validity confounding imposes threats to the validity of research

8. internal the extent to which extraneous factors cannot be responsible for the results external the extent to which the results can be generalised to other settings/environments types of validity

9. has priority internal validity the research method to improve/ensure internal validity is the experiment

10. experiment: a research study conducted under strictly controlled conditions only two factors/variables are allowed to change: the Independent Variable (cause) the Dependent Variable (effect)

11. experiment: a research study conducted under strictly controlled conditions only two factors/variables are allowed to change: the Independent Variable (cause) the Dependent Variable (effect) manipulated by the Researcher changed by the effects of the Independent Variable

12. aim: to prove with certainty independent variables dependent variables cause manipulated by us allowed to change

13. types of experiments laboratory experiment what do we compromise? field experiment/quasi experiment greater external validity

14. How do we prove causality? control group (no change in the Independent Variable) experimental group (change in the Independent Variable)

15. controls in experiments

16. in experiments we must control for: demand characteristics: experimenter and participant effects how? single-blind & double-blind procedures automation objective measures-multiple observers deception

17. in experiments we must also control for: the characteristics of participants how? random selection of participants random assignment into experimental conditions

18. END & Thank You