Time series design

It is a quasi-experimental design that involves periodic measurements on the dependent variable for a group of test units. Then the treatment is administered by the researcher or occurs naturally. After the treatment, periodic measurement are continued in order to determine the treatment or independent variable effect. This is a quasi-experiment, because there is no randomization of test units to treatments, and the timing of treatment presentation, as well as which test units are exposed to the treatment, may not be within the researcher’s control.