Good but bittersweet news for fans of The Americans. The hit FX drama series, which focuses on Russian spies living undercover as Americans in the 1980s, is currently in its fourth season, with three more episodes to go, and FX has renewed the critically acclaimed show for not one but two more seasons!
Experiments that take advantage of natural occurrences are quasi-experiments, for example, comparing achievement level of first-born children with that of later-born children; or comparing student performance at two schools, one of which has a lower student-teacher ratio.
A quasi-experiment is simply defined as not a true experiment. Since the main component of a true experiment is randomly assigned groups, this means a quasi-experiment does not have randomly assigned groups.