1 Flashcards
Difference between Observational and Experimental experiment design?
Observational has no treatment and no variable manipulation. Experimental there is a treatment and subject; 1 or more variables are manipulated.
Treatment
A condition applied to a group. The effect on the dependent variable is then observed. This includes every group in the study, including the control group.
Sampling
Randomly selecting participants.
Randomized Design
treatment to subjects randomly; randomized experiment.
Null Hypothesis
treatment means are all equal.
Alternative Hypothesis
At least two treatment means differ.
Sample Variability
How much internal variation there is in a sample/treatment groups.
How do we know treatments are statistically different?
Difference in means is large relative to sampling variability.
When do we reject the null hypothesis using the critical f-value?
When the f-value is greater than the critical f-value.
Randomized Block Design
Instead of randomly choosing independent samples, choose subjects of matched sets where the only difference between the two people is the variable we want to measure the effect of.
Blocks
Matched sets.
Block Mean
The mean for each block.
