In a scientific investigation, you have several design possibilities, as is the case with experimental research. This method involves a much more complex and rigorous data collection procedure than the classic bibliographical research .
What is experimental research?
Experimental research, also called an experiment, is a type of field research . In this method, the investigation seeks to test hypotheses involving cause-effect relationships.
In the experimental study, the researcher isolates phenomena from a given context to measure the influences of the parts on the whole. There is a concern with testing conditions, evaluating them and comparing them within the same context.
Antônio Carlos Gil, one of the experts on research methodology , states that “experimental research is the closest to scientific knowledge ” (2008, p.51).
The activities related to the experiment are developed in the field (natural environment of the studied object) or in the laboratory. In the second option, conditions can be fully controlled.
For a study to be considered experimental, it must present sample selection by probabilistic technique, control group and independent manipulation of variables .
A very important characteristic of the experiment is the rigor to select the sample. In this way, the researcher is able to establish generalizations based on his findings.
What are the characteristics of the experimental method?
- Establishment of functional relationships (cause and effect)
- Ability to manipulate variables
- probabilistic prediction
- Generalization
- Clarity in the description of the experiment
Examples of experimental research
Gil (2008, p.51) defines a scheme for carrying out experiments. The proposal is to define variables and observe their effect on the studied object.
Consider Z the studied phenomenon. The experimental conditions are A, B, C and D. At first, each of the variables needs to be controlled to measure the degree of influence. Consider the following situation:
- A, B and C produce Z
- A, B and D do not produce Z
- B, C and D produce Z
By controlling each of the factors, it was observed that C is the necessary condition to produce Z. And if it is proven that Z occurs only with factor C, excluding the others, it is possible to affirm that C is the cause of Z .
Gil’s example is very simple and only aims at understanding the process. In practice, experimental research is much more labor intensive and has many variables to control and measure.
Here are three practical examples:
- A Psychology student decided to check whether the use of picture cards helps children with Selective Mutism to speak. Thus, she started from a probabilistic prediction, that is, she wanted to find out whether a certain alternative communication action has a positive impact on language development.
- A Pedagogy student verified improvement in the math scores of students in a school after using a digital game in the classroom. Faced with this fact, he decided to apply the strategy in another educational institution, to see if it would have the same positive impact. Therefore, the experiment started from a generalization.
- A Psychology student decided to study the behavior of patients while they wait in the waiting room. To check the level of anxiety, two situations were created: an environment with calm music and yellow lighting and another with very bright lighting and magazines.
Step by step how to do it
See how to do an experimental survey, with examples at each step.
formulate a problem
What difficulty do you want to solve with your study? Create a guiding question based on the theme chosen for your work.
Francisca is a Pedagogy student. In her course completion work, she decided to research the behavior of children in the classroom. It started with the following problem:
build hypotheses
From reading scientific articles and books, or even empirical experiences , you are able to build hypotheses (verifiable statements).
Take care of the operationalization of the variables
The dependent variable (DV) is one that changes as a function of another variable. Independent variables (VI) are those that can be manipulated to determine their effect on the dependent variable.
The independent variables are applied in a given context and the researcher has the role of measuring the effects.
Create a trial plan
When designing the experimental plan, it is necessary to choose a sample of subjects and define an environment where the experiment will be carried out. This environment should allow the researcher to control the independent variables.
In order to measure the cause and effect relationship, it is necessary to randomly separate the sample into control groups. They will receive different interventions so that it is possible to verify the effects.
[model]In a municipal school in the east zone of São Paulo, there are three classes of 1st year of Elementary School. Class A will be exposed to X relaxation techniques when they return to the classroom from recess. Class B will participate in a Z-type relaxation technique, also after the break. Class C will not have this experience and the teacher will start the class immediately.
collect the data
Data collection can be performed using different techniques, such as observation . In addition, it is worth using instruments capable of facilitating recording, such as cameras and recorders.
Analyze and interpret the information
In this phase of the research, the data are evaluated and interpreted, considering the basic scheme previously defined by Gil. The researcher needs to verify the effects of the interventions, in addition to refuting or validating the previously raised hypotheses.
Some resources help in viewing and interpreting information, such as tables and graphs. Also, be sure to base your interpretation on other studies that have already been published.
