Research has found that the Nonequivalent Control-Group Design is the most widel

Question

Research has found that the Nonequivalent Control-Group Design is the most widely ysed type of Quasi-Experimental Design in educational research. With the nonequivalent control-group design, research participants are not randomly assigned to experimental and control groups, and both groups are administered a pretest and post-test. The experimental group is applied the intervention. Based on your understanding of Quasi-Experimental versus Experimental Design Research, how would you explain to a colleague or layperson specific, legitimate reasons for not choosing an experimental design?

Explanation / Answer

An experiment is a study in which the researcher manipulates the level of some variable, called the independent variable, and then measures its outcome on another variable. Experiments are powerful techniques for evaluating cause-and-effect relationships. In an experiment, participants have an equal chance of being assigned to any condition of the independent variable. So, for instance, if a researcher was examining the effects of sugar consumption on attention, she might randomly assign participants to one of three independent variable conditions: those who consume no sugar, 1 tablespoon of sugar, or 2 tablespoons of sugar.

Quasi-experiments are employed when the researcher is interested in independent variables that cannot be randomly assigned. This occurs usually when the independent variable of the study is a trait or characteristic of the participants. For example, a researcher is interested in finding the effect of personality on attention. Now, personality is inherent and so random assignment is not possible. Rather, participants would be segregated into different groups based on their domainant personality type. In situations such as these, quasi experimental measures are preferable over an experimental design.

Related Questions

Navigate

• Browse (All)
• Browse R
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.