Experimental Research

Conditions for there being a causal relationship

• Covariance: there is a relationship between the cause and the outcome

• Temporal precedence: cause needs to proceed the outcome

• Internal validity: elimination of other causal factors

Research question: PICO

• Population, intervention (expt condition), comparison (control group), outcome

class example: Is there a difference in exam performance when notes are taken on a laptop or using pen and paper in UCU students?

Between-subject design:

Within-subject design: giving participants multiple experimental conditions, compare them across the conditions rather than comparing different people to each other

Group experiment designs

Pre-test post-test:

Solomon four group design: two groups (1 treatment 1 control) are given a pretest after random assignment, another two groups are not given the pretest. Eliminates the potential impact of the pretest itself. Disadvantage: expensive, a lot of participants needed

Repeated-measures design: within subjects design. The same group gets both types of treatment and get measured both times

Counterbalanced measures design: Two groups are created. One group follows a repeated measured design, and one group is given a pretest and a posttest with multiple treatments. The order in which the treatments are given is switched

Quasi-eperiments: does not use a randomly assigned group of participants

Interrupted time series design

Ecological validity: type of external validity that is related to the setting of the research