Causal Research Methods
The manipulated variable
What is the independent variable?
As the weather gets warmer, beaches get more crowded
What is a positive correlation?
Learning and fatigue effects
What are order effects?
What is the number of independent variables in a factorial design?
The sum of all outcomes divided by the number of outcomes
What is the average (also called the mean)?
The measured variable
What is the dependent variable?
As lecture video length increases, viewers decrease
What is a negative correlation?
Used to control order effects in an experiment
What is counterbalancing?
The effect of all levels of multiple independent variables in combination
What is an interaction effect?
The most commonly observed score
What is the mode?
An extraneous variable that changes directly with the levels of the independent variable
What is a confound?
A study in which no variables are manipulated, and two variables are measured
What is a correlational study?
For 30 minutes, half of participants do progressive relaxation, the other half meditate. Measure all participants' stress at the end.
What is a between-subjects design?
The effect of one independent variable collapsing across a second independent variable
What is a main effect?
The middle point of all scores when arranged in order
What is the median?
A source of error that changes randomly across levels of the independent variable
What is a non-confounding extraneous variable?
One criterion that isnot met in correlational study and prevent causal conclusions
What is temporal precedence, that the cause comes before the effect?
On Day 1, memorize 50 words while sitting, then take a memory test. On Day 2, memorize 50 words while jogging, then take a memory test.
What is a within-subjects design?
The number of independent variables in a 2 X 2 X 3 factorial design
What is three?
Number of items correctly recalled on a memory test
What is an interval/ratio variable
Comparison groups within an independent variable
What are levels?
A u-shaped curve on a graph
(*I can't insert pictures in the free version*)
A group of medical practitioners are studying the effects of a drug on patients. One group received the drug, the other a placebo. They determined who was in which group based on a random number generator.
What is random assignment?
The number of groups in a 2 X 2 X 3 factorial design
What is twelve?
Numbers assigned as unique identifiers for participants in a study
What is a nominal variable?