(1) To determine if halfway houses improve the transition from prison, 50 inmates who will be released in a month are randomly assigned to one of two groups. One group is sent to a halfway house to participate in a program called "ReEntry." The other group stays in prison until the time of release. Two months after release, data measuring "success in job placement" are gathered on the subjects in both groups.
(a) Use the R, X, O notation to sketch the research design.
(b) Someone says that the design does not control for statistical regression since the subjects are inmates and thus represent an "extreme in their social behavior." Do you agree that the design has problems with statistical regression? Explain.
(c) Define the terms internal validity and external validity in the context of this study.
(a) R, X, O notations allow researchers to design complex experiments with a simple set of rules that are easy to read. These notations follow a standard convention. In other words R, X, O is like a shorthand for research experiments. For example think of text language on your mobile phone. "lol" means "laugh out loud" and anyone reading "lol" knows that it means "laugh out loud". The "l" is always placed in front of the "o" and that in front of the second "l". If the letters were reversed, such as "oll" the text would no longer mean "laugh out loud" but something else.
R, X, O works in the same way for research design. Let's review what R, X and O stand for:
R means that your experiment has been randomly assigned. In your homework problem, the groups of inmates were chosen randomly.
X is a treatment or program. For instance, a program to help inmates transition from prison back to work
O is the ...
Masters program research methods are examined. The expert defines the terms of internal validity and external validity in the context of this study.