1. There are many important examples of policy experiments that use random assignment, namely the Oregon Medicaid experiment. Oregon’s medicaid waitlist was so long that state officials decided to conduct a lottery to see which individuals from the wait list would receive the service (Baicker et al. 2013). Researchers used the lottery as a natural experiment that included random assignment. People selected to be apart of the Medicaid were the experimental group and those on the wait list were in the control group. There are some pratical complications with using people on a wait list as the control group, including the possibility of people from the wait list being accepted into the program while data is still being examined. Natural experiments aren’t a specific kind of experiment like quasi or pre-experimental designs. Instead, they are like a feature of the social world that allows researchers to use the logic of the experimental design to investigate the connection between two variables. 

2. There was a study conducted in which researchers divided two groups, one was with physical exercise and the other was with reading a newspaper. Participants used a digital photo distortion technique to determine their body image and mood. They did this before and after the study.The study is an example of a pre-experimental design because they took two random groups of participants that were closely observed. They needed to see if there were any effects of a physical exercise session on the body image and mood. They concluded that those participants who had higher body image problems, physical exercise has a strong effect in which the body image and mood improves. It does not seem to be any rival causal factors because there aren’t any variables that may be responsible for the results of the study. 

3. This quasi-experimental study evaluated police officers currently in the academy (pre-Field Training Officer) and their ability to handle extreme stressors that affect their mental health. The research was aimed at proving a four day psychological resilience class may help protect the officers against the incidents they will encounter once successful completion of the police training class has been achieved. Subjects were given questionnaires on resilience, mental health disturbances, and self-rating inventory for PTSD were administered prior to the subjects entering the training class and 9 months after the subjects had passed the training class. In conclusion, the study found no evidence that a 4 day training class improved an officer’s psychological resilience or mental health and officer appraisal of training benefits on resilience enhancement were largely negative. All effects yielded small effect sizes and limited practical relevance.   

4. The name of the study/article is called Understanding Drivers of Crime in East Baltimore: Resident Perceptions of Why Crime Persists. This study that was done in 2016, the researcher were trying to discover influences of criminal activity in the urban neighborhoods. Since urban neighborhoods are associated with high crime rates, unemployment, poor educational systems, poor housing conditions and health related problems, this type of setting was studied to understand triggers of crime. The study examines how residents perceive local community problems in an East Baltimore neighborhood. The way that the researchers went about carrying their research was by examining eight focus goups with participants who lived and/or work in the area to identify common neighborhood issues. Some of the problems that was taken into account was the presence of physical disorder, issues related to crime and law enforcement, lack of employment opportunities, and limited youth activities. With these issues, the neighborhood lacks collective efficacy to fix the community problems and maintain social control. This study was more of a non-exeriment and quasi-experiment because it is based on personal experience from the particiants. The study took time to describe and also research about triggers from the environment around an individual to see if it can create a criminal. The descriptions from the participants have been used to help develop their conclusions. The reason why it would also be a quasi-experiment study would be because it is trying to establish a cause and effect relationship between urban neighborhood and criminals/criminal activity.

5. An article in the Journal of Experimental Criminology 2020, a quasi-experiment was performed that examined the likelihood of arrest of co-offenders based on race.  The authors of this article decided to take a different approach than other researchers, in which they observed data of co-offenders of the same crime with the same victim(s).   They used the National Incident Based Report System (NIBR) to reconstruct the data into two levels; (1) information of the offenders offense and demographics and (2) obtaining files on the co-offenders partnership in the crime, victim characteristics and offense characteristics.  In limiting the experiment to co-offenders and examining the partnership and the differences in the arrest, the researchers noticed a difference in arrest based on the offender’s race even though, both offenders commit the crime together, to the same victim.  The quasi-experimental analysis suggested that a black offender of more likely than their white co-offender to be arrested was contrary to what the regression approach suggested.There were two major causal factors, first because the design was based on co-offenders that committed the same crime with one another, it did not identify each offender’s actual role in the crime.  Did one offender play a lesser role such as just driving the getaway vehicle and never actually causing any physical harm to the victim.  Secondly, the experiment did not utilize data pertaining to the actions of the offenders after the crime was committed and their interaction with law enforcement which may have led, to an arrest.