How exactly do researchers investigate the human mind and behavior? While there are a number of different research techniques, the experimental method allows researchers to look at cause-and-effect relationships.
In the experimental method, researchers identify and define key variables, formulate a hypothesis, manipulate the variables and collect data on the results. Extraneous variables are carefully controlled to minimize a potential impact on the outcome of the experiment.
A Closer Look at the Experimental Method in Psychology
The experimental method involves manipulating one variable to determine if changes in one variable cause changes in another variable. This method relies on controlled methods, random assignment and the manipulation of variables to test a hypothesis.
Types of Experiments
There are a few different types of experiments that researchers might choose to use. The type of experiment chosen might depend on a variety of factors including the participants, the hypothesis and the resources available to the researchers.
1. Lab Experiments
Lab experiments are very common in psychology because they allow experimenters more control over the variables. These experiments can also be easier for other researchers to replicate. The problem, of course, is that what takes place in a lab is not always identical to what takes place in the real world.
2. Field Experiments
Sometimes researchers might opt to conduct their experiments in the field. For example, let's imagine that a social psychologist is interested in researching prosocial behavior. The experimenter might have a person pretend to faint and observe to see how long it takes onlookers to respond. This type of experiment can be a great way to see behavior in action in realistic settings. However, it makes it more difficult for the researchers to control the variables and can introduce confounding variables that might influence the results.
While lab and field experiments represent what are known as true experiments, researchers can also utilize a third type known as a quasi-experiment. These are often referred to as natural experiments because the researchers do not have true control over the independent variable. Instead, the treatment level is determined by the natural conditions of the situation. A researcher looking at personality differences and birth order, for example, is not able to manipulate the independent variable in the situation. Treatment levels cannot be randomly assigned because the participants naturally fall into pre-existing groups based on their birth order in their families.
So why would a researcher choose to use a quasi-experiment. This is a good choice in situations where scientists and interested in studying phenomena in natural, real-world settings. It is also a good choice in situations where researchers cannot ethically manipulate the independent variable in question.
Key Terms to Know
In order to understand how the experimental method works, there are some key terms you should first understand.
The independent variable is the treatment that the experimenter manipulates. This variable is assumed to cause some type of effect on another variable. If a researcher was investigating how sleep influences test scores, the amount of sleep an individual gets would be the independent variable.