Extraneous variables include anything other than the dependent and independent variables in a psychology experiment. These variables often present challenges to the researcher and can also introduce errors in the experiments. Researchers try to control these extraneous variables in order to retain a form of consistency in the psychology experiments. The researchers often achieve control over the extraneous variables by holding them constant in all of their experiments (Montes and Weatherly 88). Some of the extraneous variable that can affect a psychological experiment include the environment around the subject, such as the temperature, noise or lighting. They can also entail other factors that are specific to the subject, such as the background, height, personality or weight.
The extraneous variables that are environmental can be easily controlled by the researcher by holding the constant. However, the ones that have to do with the personal attributes of the subject are harder to control because they vary a lot (Cherry par 4). The first thing that the researcher ought to do as he/she seeks to control the extraneous variables is to determine and identify the variables that might affect the dependent variables. After the identification of the extraneous variables, the researcher can then decide how to best control them.
There are two approaches used by researcher to control the effects of the extraneous variables on the dependent variable. The first method is the use of standardized procedures. This entails making all the external aspects of an experiment identical for all of the subjects (Cherry par 4). This is most effective in the control of environmental extraneous factors. The second method of controlling extraneous variables is the use of random assignment of the subjects to either the experimental group or the control group. It helps in minimizing the impact of their personal characteristics on the experiment.
Cherry, Kendra. “What Is An Extraneous Variable? | Explore Psychology.” Explore Psychology. N.p., 2016. Web. 11 Apr. 2018.
Montes, Kevin S., and Jeffrey N. Weatherly. “Differences in the Gambling Behavior of Online and Non-Online Student Gamblers in a Controlled Laboratory Environment.” Journal of Gambling Studies (Online) 33.1 (2017): 85-97. ProQuest. Web. 10 Apr. 2018. https://search.proquest.com/docview/1871444851/A660A45234E4D17PQ/8?accountid=1611