Forming a Hypothesis
The first step of a psychological investigation is to identify an area of interest and develop a hypothesis that can then be tested. While a hypothesis is often described as a hunch or a guess, it is actually much more specific. A hypothesis can be defined as an educated guess about the relationship between two or more variables.
For example, a researcher might be interested in the relationship between study habits and test anxiety. They would then propose a hypothesis about how these two variables are related, such as "test anxiety decreases as a result of effective study habits."
In order to form a hypothesis, you must start by collecting as many observations about something as you can. Next, it is important to evaluate these observations and look for possible causes of the problem. Create a list of possible explanations that you might want to explore. After you have developed some possible hypotheses, it is important to think of ways that you could confirm or disprove each hypothesis through experimentation.
In the scientific method, falsifiability is an important part of any valid hypothesis. This does not mean that the hypothesis is false; instead, it suggests that if the hypothesis were false, researchers could demonstrate this falsehood.
Study habits and test anxiety are the two variables in this imaginary study. A variable is a factor or element that can be changed and manipulated in ways that are observable and measurable. However, the researcher must also define exactly what each variable is using what are known as operational definitions. These definitions explain how the variable will be manipulated and measured in the study.
In our previous example, a researcher might operationally define the variable 'test anxiety' as the results on a self-report measure of anxiety experienced during an exam. The variable ‘study habits’ might be defined by the amount of studying that actually occurs as measured by time.
Why do psychologists need to provide operational definitions for each variable? These precise descriptions of each variable are important because many things can be measured in a number of different ways. One of the basic principles of any type of scientific research is that the results must be replicable. By clearly detailing the specifics of how the variables were measured and manipulated, other researchers can better understand the results and repeat the study if needed.
Some variables are more difficult than others to define. How would you operationally define a variable such as aggression? For obvious ethical reasons, researchers cannot create a situation in which a person behaves aggressively toward others. In order to measure this variable, the researcher must devise a measurement that assesses aggressive behavior without harming other people. In this situation, the researcher might utilize a simulated task to measure aggressiveness.
Popper, K. (1959). The Logic of Scientific Discovery, Basic Books, New York, NY.