Linear and nonlinear relationships between variables

 Linear and Nonlinear Relationships Between Variables

How two things are related or the degree to which they are related is often a question in any area of research, including forensic psychology research. A researcher might ask these questions: To what degree are drug use and criminal recidivism related? Are mental illness and violence related? To what degree is an increase in police patrols related to a decrease in crime rates?

Each of these forensic psychology research questions can be addressed using a correlational design. Correlational designs help determine if there is a relationship between variables. The relationship may be positive, meaning there is a positive linear relationship between the two variables; the relationship may be negative, which means there is a weak or nonexistent linear relationship between the two variables; or, the relationship may be curvilinear, which means that at times there appears to be a relationship and at times there does not.

To prepare for this Discussion:

• Review Chapter 9 in your course text, Research Methods for the Behavioral Sciences. Pay attention to the descriptions and examples of linear and nonlinear relationships, positive and negative linear relationships, and curvilinear relationships.
• Consider how these relationships are determined and what impact each type of relationship may have on a researcher’s ability to make predictions.
• Using the Walden Library, select and review two or three articles on criminal recidivism, violent crime, or domestic violence in which the variables have positive and negative linear relationships.
• Consider the implications if the variables had a curvilinear relationship instead.

With these thoughts in mind:

Post by Day 4 a description of two variables that have a positive linear relationship and two variables that have a negative linear relationship in the research articles you reviewed. Then, explain the implications on the studies if each of those variables had a curvilinear relationship instead.

Be sure to support your postings and responses with specific references to the Learning Resources.

Read a selection of your colleagues’ postings.