Experimenter Bias: An Overview
Experimenter bias is a form of bias that is introduced into the research process by the experimenter. It occurs when a researcher’s expectations or preconceptions about the outcome of the experiment influence the results. This can affect the validity of the research results and lead to inaccurate conclusions. Experimenter bias can be unintentional or intentional, and it can occur in various stages of the research process.
Experimenter bias can be divided into two main categories: subtle and overt. Subtle bias is less obvious and often occurs unconsciously. It can involve the researcher’s expectations about the results, the researcher’s choice of words or questions, or the researcher’s interpretation of the results. Overt bias is more obvious and intentional. It can involve the researcher deliberately manipulating the results or not following standard research protocols.
The most common form of experimenter bias is the Expectancy Effect. This occurs when the experimenter’s expectations about the outcome of the experiment influence the results. For example, if the experimenter expects the experiment to yield a certain result, they may take steps to ensure that result is achieved. This could involve changing the conditions of the experiment, selectively choosing participants, or altering the data.
Another form of experimenter bias is the Hawthorne Effect. This occurs when researchers become aware that they are being observed and change their behavior in response. This often occurs in experiments involving humans, as people may alter their behavior when they know they are being observed.
Experimenter bias can have serious implications for the validity of research results. To reduce the risk of bias, researchers should be aware of it and take steps to minimize it. This can include using randomization to assign participants to conditions, blinding the experimenter to the conditions, and using objective measures. Researchers should also be aware of their own expectations and preconceptions and make sure these do not influence the results.
In conclusion, experimenter bias is a form of bias that can occur in various stages of the research process. It can have serious implications for the validity of research results and should be taken into account when designing experiments.
References
Gigerenzer, G., & Murray, D. J. (1987). Cognition as intuitive statistics. Lawrence Erlbaum Associates.
Kahneman, D. (2003). Maps of bounded rationality: Psychology for behavioral economics. The American Economic Review, 93(5), 1449-1475.
Kirk, R. (1996). Experimental design: Procedures for the behavioral sciences (3rd ed.). Pacific Grove, CA: Brooks/Cole.
Sternberg, R. J., & Sternberg, K. (2006). Cognitive psychology (5th ed.). Belmont, CA: Wadsworth.