How do researchers explore the human mind and behavior? Although there are a number of different research methods, natural science experiments allow researchers to look at causal relationships. They identify and define key variables, formulate a hypothesis, manipulate variables and collect data on results. Extraneous variables are carefully monitored to minimize potential impact on the result.
A closer look at the experimental method in psychology
An experiment, laboratory, natural, or any other, involves manipulating one variable to determine if changes in one variable can cause changes in another. This method is based on controlled methods, random assignment and manipulation of variables to test a hypothesis.
Types of Experiments
There are several different types of experiments that researchers might use. Each of them may depend on many factors, including participants, hypothesis and resources available to researchers:
- Laboratory experiments are very common in psychology because they allow experimenters to better control variables. These experiments may also be easier to carry out by other researchers. The problem, of course, is that what happens in the laboratory is not always identical to what happens in the real world.
- A natural experiment is a so-called field experiment. Sometimes, researchers may prefer to conduct their research in a natural environment. For example, suppose a social psychologist is interested in researching a certain type of social behavior. This type of experiment can be a great way to see behavior in action under realistic conditions. However, this makes it difficult for researchers to control the variables, and may introduce mixed variables that can influence the results.
- Quasi-experiments. Although laboratory and natural experiments in psychology are a group of the most popular methods, researchers can also use the third type, known as a quasi-experiment. They are often referred to as natural experiments because researchers do not have true control over an independent variable. Instead, the level of goal achievement is determined by the natural conditions of the situation. This is a good choice in situations where scientists study phenomena in natural, real conditions. It is also a good choice in situations where researchers cannot, for ethical reasons, manipulate the independent variable in question.
Key Terms
To understand how the natural experiment method works, there are several key terms:
- An independent variable is the object that the experimenter is manipulating. This variable is supposed to cause some effect for another variable. If a researcher studies how sleep affects the quality of a math test, the amount of sleep a person gets will be an independent variable.
- The dependent variable is the effect that the experimenter measures. In our previous example, test scores will be a dependent variable.
- Operational definitions are necessary for the experiment. When we say that something is an independent or dependent variable, we need to have a very clear and concrete definition of its meaning and scope.
- A hypothesis is a preliminary statement or conjecture about a possible relationship between two or more variables. In our previous example, the researcher may suggest that people who get more sleep will take the math test better the next day. The purpose of the experiment is to support or not support this hypothesis.
Experimental process
Psychologists, like other scientists, use the scientific method when conducting an experiment. The scientific method is a set of procedures and principles that determine how scientists develop research questions, collect data and draw conclusions. There are four main stages of the process:
- Hypothesis formation.
- Research design and data collection.
- Data analysis and conclusions.
- Exchange of results.
What is a natural experiment?
A natural experiment is an empirical study in which individuals (or clusters of individuals) are exposed to experimental and control conditions independent of researchers, but the process itself looks natural. This is a kind of observational study. A natural experiment is the most useful method when there is a pronounced exposure with a clearly defined subpopulation (and lack of exposure), so that changes in the results can be plausibly attributed to the exposure. In this sense, the difference between a natural experiment and a non-experimental observational study is that the former includes a comparison of conditions that pave the way for a causal conclusion, but the latter does not.
Natural experiments are research projects where controlled experiments are extremely difficult to implement or unethical, for example, in several areas of research covered by epidemiology (for example, assessing the health effects of varying degrees of exposure to ionizing radiation in people living near Hiroshima during an atomic explosion) , economics (for example, evaluating the economic return on adult education in the United States), political science, psychology, and social sciences.
Natural Experiment Conditions
Key conditions and features of experimental research include manipulation and control. Manipulation in this context means that the experimenter can control the subjects of the study, as well as what impact they feel on themselves. You can manipulate at least one variable. Control tests can answer only some types of epidemiological questions, and they are not useful in researching questions for which a random task is either unfeasible or unethical.
As an example, suppose an investigator is interested in the health effects of poor housing. Since the practical or ethical random distribution of people according to variable housing conditions is impractical, this subject is difficult to study using an experimental approach. However, if a housing policy has been changed , such as a lottery for subsidized mortgages, which would allow some people to move to more desirable housing, leaving other similar people in their former poor-quality housing, it might be possible to use this policy change to study the impact of the housing change health conditions.
In another example, a natural experiment in Helen (Montana, USA) is well known, according to which smoking was banned in all public places for a six-month period. Researchers subsequently reported a 60 percent drop in heart attacks in the study area during the duration of the ban.
Scientific research method
The experiment is the main method of research in science. Key functions are variable control, careful measurement and the establishment of cause-effect relationships. This is a study in which the hypothesis is scientifically verified. In the experiment, an independent (reason) is controlled and a dependent variable (effect) is measured, and any extraneous variables are controlled. The advantage is that experiments are usually objective. The views and opinions of the researcher should not affect the results of the study. This is good, as it makes the data more reliable and less biased.