Extraneous variables are the undesirable variables that affect or influence the relationship between the variables that are being examined in an experiment and therefore add errors to the experiment and therefore leading to difficulty in attaining the desired results (Powers & Knapp, 2013). It is up to the researcher to limit or control the effects the extraneous factor has on the results to reduce the margin of error and also have results that can be used to make a reliable conclusion. In an experiment, it is also important to make sure that the sample selected from the entire group is representative to avoid the big difference or the margin of error in coming up to a conclusion.
Some of the considerations made in controlling the extraneous variable sure the participant’s variables and their effects. The participant’s variables such as such as the age and the knowledge level should be minimized the difference between the participants (Soneye, 2014). The researcher variables such as the researcher behaviors also to some extent affect the responses of the participants and this, therefore, should be made consistent in the entire experiment (Soneye, 2014). In situational variables, the setting or the venue for the experiment should be controlled such as keeping some factors constant like sound, light, and temperature (Soneye, 2014). Most of the research is done with assumptions, and therefore there are always chances of errors in such cases due to the effects of the extraneous variables.
Soneye, B. (2014). Control of Extraneous Variable. Retrieved from http://www.academia.edu/9386003/Control_of_Extraneous_Variable
Powers, B. A., & Knapp, T. R. (2013). Dictionary of nursing theory and research. New York, NY: Springer Pub. Co.