What type of research is characterized by the manipulation of variables to determine cause-effect relationships?

Experimental research is characterized by the manipulation of one or more independent variables to observe the effect on a dependent variable, thereby establishing cause-effect relationships. This type of research typically involves the use of controlled conditions, where participants are randomly assigned to different groups to ensure any differences observed can be attributed to the manipulation of the variables rather than other extraneous factors.

For example, if researchers wanted to determine whether a new teaching method improves student performance, they might randomly assign one group of students to the new method while another group continues with the traditional method. By comparing the performance of both groups after the intervention, researchers can draw conclusions about the causal impact of the teaching method.

In contrast, correlational research examines the relationships between variables without manipulating them, descriptive research focuses on providing a detailed account of a phenomenon without analysis of relationships or causation, and cross-sectional research analyzes data from a population at a specific point in time rather than manipulating variables for experimental purposes.