Experimental and Non-experimental Research Design
Experimental research designs involve research conducted in the lab whereby the researcher can manipulate the predictor variable and subjects to identify a cause-and-effect relationship. On the other hand, non-experimental research design refers to that study in which the researcher cannot control the predictor variables but instead depends on the observations to formulate conclusions (Kowalczyk, 2018). This paper will address several examples of the two will be highlighted as well as contrasting the levels of controls that are applied to each.
In conducting experimental research, the researcher uses two groups to perform the study, whereby one group is referred to as the experimental group while the other is called the placebo group. Examples of experimental research include all scientific researches that are carried out in the lab such as analyzing blood samples to deduce bacteria in it so as to deduce a disease that an individual may be suffering from (Richters & Melis, 2017). Another example is the test on the influence of a fertilizer to the height of a plant whereby it would be necessary to control the amount of sunlight, type of soil and amount of water subjected to the plant (Richters & Melis, 2017).
One example of non-experimental research is one whereby researchers investigate the psychological effects of long-term use of ecstasy. In such a study, the researcher cannot do actual tests on the subjects but can only make conclusions by observing the subjects of the research. Another instance of non-experimental research is whereby researchers may want to compare the memory of cannabis users against those of non-users. In such a case the subjects may be given certain tests to compare their memory which will be assessed on their response to the tests (Kowalczyk, 2018) .
There are several differences in the levels of control that can be applied to experimental and non-experimental research designs. To begin with, the methodology that is used to carry out the two types of research is contrasting. For the experimental research, the researchers are able to conduct actual experiments on people and hence can manipulate and control the predictor variables. On the other hand, in non-experimental research, the researcher is only able to observe and interpret the subjects hence cannot manipulate the same (Kowalczyk, 2018).
Secondly, in experimental research design, there is a cause-effect relationship in the study such that it is possible to deduce that the occurrence of event x causes y since it occurs directly. However, in non-experimental research, the researcher cannot unconditionally say that an event x causes y since the events are not linked directly but are deduced depending on observation and reasoning (Kowalczyk, 2018).
Kowalczyk, D. (2018). Non-Experimental and Experimental Research: Differences, Advantages & Disadvantages. Study.Com.
Richters, A., & Melis, R. (2017). Quasi-experimental study designs: making a case for non-experimental designs in the spectrum. Journal Of Clinical Epidemiology, 91, 146. doi: 10.1016/j.jclinepi.2017.07.012