Commonly used in sciences such as sociology, psychology, physics, chemistry, biology and medicine, experimental research is a collection of research designs which make use of manipulation and controlled testing in order to understand casual processes. To determine the effect on a dependent variable, one or more variables need to be manipulated.
Experimental research is used where:
- time priority in a causal relationship.
- consistency in a causal relationship.
- magnitude of the correlation is great.
In the strictest sense, experimental research is called a true experiment. This is where a researcher manipulates one variable and controls or randomizers the rest of the variables. The study involves a control group where the subjects are randomly assigned between groups. A researcher only tests one effect at a time. The variables that need to be test and measured should be known beforehand as well.
Another way experimental research can be defined is as a quasi experiment. It’s where scientists are actively influencing something in order to observe the consequences.
The aim of experimental research is to predict phenomenons. In most cases, an experiment is constructed so that some kinds of causation can be explained. Experimental research is helpful for society as it helps improve everyday life.
When a researcher decides on a topic of interest, they try to define the research problem, which really helps as it makes the research area narrower thus they are able to study it more appropriately. Once the research problem is defined, a researcher formulates a research hypothesis which is then tested against the null hypothesis.
In experimental research, sampling groups play a huge part and should therefore be chosen correctly, especially of there is more than one condition involved in the experiment. One of the sample groups usually serves as the control group while the others are used for the experimental conditions. Determination of sampling groups is done through a variety of ways, and these include:
- probability sampling
- non-probability sampling
- simple random sampling
- convenience sampling
- stratified sampling
- systematic sampling
- cluster sampling
- sequential sampling
- disproportional sampling
- judgmental sampling
- snowball sampling
- quota sampling
Being able to reduce sampling errors is important when researchers want to get valid results from their experiments. As such, researchers often make adjustments to the sample size to lessen the chances of random errors.
All this said, what are the popular examples of experimental research?
Stanley Milgram Experiment – Conducted to determine whether people obey orders, even if its clearly dangerous. It was created to explain why many people were slaughtered by Nazis during World War II. The killings were done after certain orders were made. In fact, war criminals were deemed just following orders and therefore not responsible for their actions.
Law of Segregation – based on the Mendel Pea Plant Experiment and was performed in the 19th century. Gregory Mendel was an Austrian monk who was studying at the University of Vienna. He didn’t know anything about the process behind inherited behavior, but found rules about how characteristics are passed down through generations. Mendel was able to generate testable rather than observational data.
Ben Franklin Kite Experiment – it is believed that Benjamin Franklin discovered electricity by flying his kite into a storm cloud therefore receiving an electric shock. This isn’t necessarily true but the kite experiment was a major contribution to physics as it increased our knowledge on natural phenomena.
But just like any other type of research, there are certain sides who are in support of this method and others who are on the opposing side. Here’s why that’s the case:
List of Advantages of Experimental Research
1. Control over variables
This kind of research looks into controlling independent variables so that extraneous and unwanted variables are removed.
2. Determination of cause and effect relationship is easy
Because of its experimental design, this kind of research looks manipulates variables so that a cause and effect relationship can be easily determined.
3. Provides better results
When performing experimental research, there are specific control set ups as well as strict conditions to adhere to. With these two in place, better results can be achieved. With this kind of research, the experiments can be repeated and the results checked again. Getting better results also gives a researcher a boost of confidence.
Other advantages of experimental research include getting insights into instruction methods, performing experiments and combining methods for rigidity, determining the best for the people and providing great transferability.
List of Disadvantages of Experimental Research
1. Can’t always do experiments
Several issues such as ethical or practical reasons can hinder an experiment from ever getting started. For one, not every variable that can be manipulated should be.
2. Creates artificial situations
Experimental research also means controlling irrelevant variables on certain occasions. As such, this creates a situation that is somewhat artificial.
3. Subject to human error
Researchers are human too and they can commit mistakes. However, whether the error was made by machine or man, one thing remains certain: it will affect the results of a study.
Other issues cited as disadvantages include personal biases, unreliable samples, results that can only be applied in one situation and the difficulty in measuring the human experience.
Also cited as a disadvantage, is that the results of the research can’t be generalized into real-life situation. In addition, experimental research takes a lot of time and can be really expensive.
4. Participants can be influenced by environment
Those who participate in trials may be influenced by the environment around them. As such, they might give answers not based on how they truly feel but on what they think the researcher wants to hear. Rather than thinking through what they feel and think about a subject, a participant may just go along with what they believe the researcher is trying to achieve.
5. Manipulation of variables isn’t seen as completely objective
Experimental research mainly involves the manipulation of variables, a practice that isn’t seen as being objective. As mentioned earlier, researchers are actively trying to influence variable so that they can observe the consequences.