Hypotheses are a crucial part of the scientific thinking process, and most professional scientific endeavors are hypothesis-driven. That is, they seek to address a specific, measurable, and answerable question. A well-constructed hypothesis has several characteristics: it is clear, testable, falsifiable, and serves as the basis for constructing a clear set of experiments that will allow the student to discuss why it can be accepted or rejected based on the experiments. We believe that it is important for students who publish with JEI to practice rigorous scientific thinking through generating and testing hypotheses.
When you assess whether your manuscript has a clear, well-constructed hypothesis, please ask whether it meets the following five criteria:
Some research is not hypothesis-driven. Terms used to describe non-hypothesis-driven research are ‘descriptive research,’ in which information is collected without a particular question in mind, and ‘discovery science,’ where large volumes of experimental data are analyzed with the goal of finding new patterns or correlations. These new observations can lead to hypothesis formation and other scientific methodologies. Some examples of discovery or descriptive research include an invention, explaining an engineered design like a program or an algorithm, mining large datasets for potential targets, or even characterizing a new species.
Another way to assess whether your research is hypothesis-driven is by analyzing the experimental setup. What variables in the experiment are independent, and which are dependent? Do the results of the dependent variable answer the scientific question? Are there positive and negative control groups?
While your hypothesis does not have to be completely novel within the larger field of your research topic, it cannot be obvious to you, given the background information or experimental setup. You must have developed the hypothesis and designed experiments to test it yourself. This means that the experiments cannot be prescribed – an assigned project from an AP biology course, for example.
Example 1: “Disease X results from the expression of virulence genes.” Instead the hypothesis should focus on the expression of a particular gene or a set of genes.
Example 2: “Quantifying X will provide significant increases in income for industry.” This is essentially untestable in an experimental setup and is really a potential outcome, not a hypothesis.
Hypothesis statements that contain words like “and” and “or” are ‘compound hypotheses’. This makes testing difficult, because while one part may be true the other may not be so. When your hypothesis has multiple parts, make sure that your experiments directly test the entire hypothesis. Possible further implications that you cannot test should be discussed in Discussion.
The hypothesis should not address your capabilities. “Discovering the mechanism behind X will enable us to better detect the pathogen.” This example tests the ability of the researchers to take information and use it; this is a result of successful hypothesis-driven research, not a testable hypothesis. Instead, the hypothesis should focus on the experimental system. If it is difficult to state the hypothesis without misdirecting to the researcher, the focus of the research may be discovery science or invention-based, and should be edited to incorporate a properly formulated hypothesis.
Please contact the JEI Editorial Staff at firstname.lastname@example.org if you have any questions regarding the hypothesis of your research.