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Natural Experiment and Quasi-Experiment study designs share which of the following characteristics? (1) The researcher controls the process/mechanism of randomization to assign experimental units to either a treatment group or control group, (2) Quasi-experiments are commonly used to study some policy/phenomenon that affects one group, but does not affect another group that is otherwise similar (except for regarding the focal policy/phenomenon). (3) Natural Experiments and Quasi-Experiment study designs are ranked above Cohort Studies in the "hierarchy" of study designs (with respect to the level of causal inference that may be appropriate)