Experiments are largely conducted to find out if certain phenomena exist or not. To find out this, scientists conduct studies in various ways. One of the methods of finding out the existence of a phenomenon is through true experiments. Empirically, true experiments are a technique that social scientists use two variables, independent and dependent (Borg, Gall, & Gall, 1993). To achieve their objectives, an independent variable is manipulated, while the dependent variable is measured for results.
True experiments engage a random selection of subjects purposely to neutralize the potential bias of the person experimenting. Characteristically, true experiments employ the following designs to achieve the desired results (Borg, Gall, & Gall, 1993).
- Control groups
- Random selection
- Random assignments are given to control and experimental grouping
- Randomly assigning groups to control and experimental clusters
True experiments work in a way that all aspects of the research are kept stable except one, the one that the researcher is investigating. For instance, if a researcher is investigating the best method of teaching children how to read, the aspect that will be changed is called the independent variable, in this respect, the teaching method will be the independent variable. In this experiment, the measure of the ability of children to read becomes the dependent variable. In this example, the ability of children to read depends on the methods of teaching. Further, the variable that is being manipulated is the independent variable while the dependent aspect is the change of childrens ability to read, which is being studied by the researcher. Nevertheless, there are factors that true experiments encounters, which are referred to as confounding variables. Confounding variables are aspects that might affect results hence leading to false outcomes. In the example that I have given, confounding variables might be different instructions that were given by the researcher at the time of experimenting.
True experiment advantages
According to Shaughnessy, Zechmeister & Zechmeister (2009), there are advantages as to why true experiments are widely used, one of the advantages is that true experiment is the only means by which cause and effect can be established. Another advantage is that this experiment allows variables accurate control of aspects of the research (Shaughnessy, Zechmeister & Zechmeister 2009). This makes it possible for a scientist to conclude that one variable is the causative effect of the other. Furthermore, true experiments can be replicated, so that, no single conclusion can be drawn from the experiment. Another advantage is that true experiments quantitatively give results so that the researcher can find the inferential interpretation of the data. Such interpretations help the researcher to give conclusions to the likelihood of a certain phenomenon to happen by chance. Further, true experiments have been known to have greater internal validity than any other method.
Limitations of a true experiment
Nevertheless, while this method has been hailed across as the best scientific experiment, there are limitations that researchers need to be aware of. For instance, true experiments are mostly carried out in the laboratory, such an environment is said to be too narrow or limiting. Another limiting factor is that true experiments are typically artificial and they do not depict a true-life situation. This is because the environment is artificially created, and sometimes people are obliged to perform unusual tasks for the sake of the experiment (Shaughnessy, et al 2009).
Borg, W. R., Gall, J. P., & Gall, M. D. (1993), Applying educational research (3rd ed.). New York: Longman.
Shaughnessy, J. J., Zechmeister, E. B., & Zechmeister, J. S. (2009). Research methods in psychology (8th ed.). New York: McGraw Hill.