Design of Experimental Research with Examples
C.F. Poole, S.K. Poole, 2012 opine,
“Experimental design is an efficient method of optimizing the experimental conditions for SPE to maximize the amount of useful information obtained with the minimum number of experiments. It provides a more efficient and complete optimisation compared with the ‘vary one factor at a time’ approach with other factors assigned fixed values.”
Experimental research refers to the method of research that uses a scientific method known as the gold standard. It performs experiments to reach conclusions based on the findings of some previous research. It is used in fields such as physical sciences, social sciences, education, and psychology. Creswell, 2012 states,
“An experimental research is a testing the independent variable (s) to determine whether it influences a dependent variable(s).”
Types of Experimental Research
There are three main types of experimental research design which are as follows:
1. Pre-experimental research design
2. True experimental research design
3. Quasi-experimental research design
Design of Experimental Research
1. Pre-experimental Research Design:
It is considered to be the most cost effective and simplest form of experimental research design in Statistics. A group or various groups are kept under observation in this method and some factors are recognised for the cause and effect in the end. The research is mostly conducted with an aim to understand whether further investigations are required for the targeted group or not. This method has three main types:
● Static Group Comparison
● One-group Pretest-posttest Experimental Research Design
● One-shot Case Study Experimental Research Design
2. True-experimental Research Design:
It relies on statistical hypotheses to prove or disprove it and hence, it is the most accurate form of experimental research design. This method is most commonly used in Physical Science. True experimental research design is the sole design that establishes the cause and effect relationship within the groups. There are certain factors that need to be satisfied in this method which include:
● Random variable
● Variable can be manipulated by the researcher
● Control Groups (A group of participants are familiar with the experimental group, but the experimental rules do not apply to them)
● Experimental Group (Research participants where experimental rules are applied)
3. Quasi-Experimental Design:
It is similar to true experimental design but in quasi-experimental design, the participants of the groups are not randomly assigned. Hence, the cause or effect conclusion cannot be made by the researcher. Due to this, the participants cannot be assigned to the group.
Steps of Experimental Research
1. Define the variables and explain their relationship.
2. Prepare a specific hypothesis that can be tested.
3. Design experimental treatments to manipulate the independent variable.
4. Assign subjects to groups, either between-subjects or within-subjects.
5. Plan the process of measuring the dependent variable.
Ajit Singh opines,
“Experimental research is a study that strictly adheres to a scientific research design. It includes a hypothesis, a variable that can be manipulated by the researcher, and variables that can be measured, calculated and compared. Most importantly, experimental research is completed in a controlled environment.”
Experiments are context-dependent, and a good experimental research is based on all the considerations of the study system to produce valid and relevant information for the research question. According to The Experience Journal,
“Experimental research is a study conducted with a scientific approach using two sets of variables. The first set acts as a constant, which you use to measure the differences of the second set.”
Shrutika Sirisilla adds,
“Experimental research design is a framework of protocols and procedures created to conduct experimental research with a scientific approach using two sets of variables. Herein, the first set of variables acts as a constant, used to measure the differences of the second set. The best example of experimental research methods is quantitative research.”