Experimental research is commonly used in sciences such as sociology and psychology; physics, chemistry, biology and medicine etc. it Involves the use of random assignment to place participants in two groups: an experimental group which receives intervention, and another control group without any intervention. It is using a positive control for you to base it or compare it in your result. It is a collection of research designs which use manipulation and controlled testing to understand causal processes. Generally, one or more variables are manipulated to determine their effect on a dependent variable. English
An experiment is an orderly procedure carried out with the goal of verifying, refuting, or establishing the validity of a hypothesis. Controlled experiments provide insight into cause-and-effect by demonstrating what outcome occurs when a particular factor is manipulated. Controlled experiments vary greatly in their goal and scale, but always rely on repeatable procedure and logical analysis of the results.
• Pretest-Posttest Design
Check whether the groups are different before the manipulation starts and the effect of the manipulation. Pretests sometimes influence the effect.
• Control Group
Control groups are designed to measure research bias and measurement effects, such as the Hawthorne Effect or the Placebo Effect. A control group is a group not receiving the same manipulation as the experimental group. Experiments frequently have 2 conditions, but rarely more than 3 conditions at the same time.
• Randomized Controlled Trials
Randomized Sampling, comparison between an Experimental Group and a Control Group and strict control/randomization of all other variables
• Solomon Four-Group Design
With two control groups and two experimental groups. Half the groups have a pretest and half do not have a pretest. This to test both the effect itself and the effect of the pretest.
The major feature that distinguishes experimental research from other types of research is that the researcher manipulates the independent variable.
ADVANTAGES AND DISADVANTAGES.
Advantages of experimental research.
• Insight into methods of instruction.
• Researcher has control and ability to change experiment if the answers are inconclusive, this allows for less time wasting in experiments.
• Humans perform other kinds of experiments anyway so the human input should not be an issue.
Disadvantages of experimental research.
• Uses casual relationships that may be bias.
• Scientist manipulates values so they may not be making a completely objective experiment.
• People can be influenced by what they see around them and may give answers that they think the researcher wants to hear rather than how they think and feel on a subject.
The aim of an analysis is to draw a conclusion, together with other observations. The researcher might generalize the results to a wider phenomenon, if there is no indication of confounding variables “polluting” the results.
If the researcher suspects that the effect stems from a different variable than the independent variable, further investigation is needed to gauge the validity of the results. An experiment is often conducted because the scientist wants to know if the independent variable is having any effect upon the dependent variable. Variables correlating are not proof that there is causation.
Experimental research is seen as true research by many scientists. This is where there are different versions of the same situation and each time the experiment is done, one variable is different. This will show what the differences are in the reactions of the subjects and also allow the scientist to work out what they feel is the best and therefore the deciding factor in the experiment results.
There are some people who feel that the human input is a disadvantage in these studies as humans do always have their own thoughts and can manipulate the results. There is also another thought that testing on humans is also a disadvantage as you cannot tell whether their answers or reactions are true or a show for the experiment.
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