Experimental Design Flashcards
Steps in experimental design
Research question Variables Hypotheses Research design Analysis Answer question
Question types
Difference
Relationship
Independent variable
Variable that is changed
Dependent variable
Variable that is measured
Confounding variables
Other variables which may have an effect
Need to be controlled
Null hypothesis
There will be no difference/relationship between the variables
Experimental hypothesis
There will be a difference/relationship between the variables
Research design
Between-subjects design
Within-subjects design
Between-subjects design
Different participants in each condition
Within-subjects design
Same participants in each condition
Advantages of within-subjects design
Less chance of confounders
Fewer people needed
Disadvantages of within-subjects design
Order effect
Carry-over effect
What is counterbalancing?
Changing the order in which participants take part in each condition
Hypothesis testing
Find H1 and H0 Calculate 95% confidence interval Does it contain H0? Yes > 95% chance population mean = H0 No < 5% chance population mean =H0 (can reject null)
Summary of results
The average level of DV (mean=… , SD= ….) was lower/higher after IV2 compared to IV1 (mean = …, SD = … ; mean difference = …. , 95% CI = …. With 95% chance, people in the population who do IV2 will be between (CI) lower/higher than IV1. This indicates that it has had an effect.
