What Is A Research (Or Scientific) Hypothesis?
A Plain-Language Explanation & Definition (With Examples)
By: Derek Jansen (MBA) | June 2020
If you’re new to the world of research, or it’s your first time writing a dissertation or thesis, you’re probably noticing that the words “research hypothesis” and “scientific hypothesis” are used quite a bit, and you’re wondering what they mean in a research context.
“Hypothesis” is one of those words that people use loosely, thinking they understand what it means. However, it has a very specific meaning within academic research. So, it’s important to understand the exact meaning before you use the word in your academic writing.
What is a hypothesis (generally speaking)?
Let’s start with the general definition of a hypothesis (not a research hypothesis or scientific hypothesis), according to the Cambridge Dictionary:
Hypothesis: an idea or explanation for something that is based on known facts but has not yet been proved.
In other words, it’s a statement that provides an explanation for why or how something works, based on facts (or some reasonable assumptions), but that has not yet been specifically tested. For example, a hypothesis might look something like this:
A consumer’s likelihood to trust a financial advisor is influenced by their perception of the competence and skill of the financial advisor.
In this example, we’re making a statement about the relationship between perceptions of competence and likelihood to trust. The link between the two seems plausible and logical, but it is not proven (at least not in a scientifically rigorous way in every possible context). So, this qualifies as a hypothesis (loosely speaking). In the world of research, however, a hypothesis needs a few more criteria to constitute a true research hypothesis or scientific hypothesis. Let’s take a look at these criteria.
What is a research hypothesis?
A research hypothesis (also called a scientific hypothesis) is a statement about the expected outcome of a scientific study (for example, a dissertation or thesis). For a hypothesis to be a genuine research hypothesis, this statement needs to have three attributes – specificity, testability and falsifiability. Let’s take a look at these more closely.
Hypothesis Essential #1: Specificity & Clarity
A good research hypothesis needs to be very clear about what’s being assessed (who and what is involved) and very specific about the expected outcome.
Hypothesis 1: A customer’s perception of a financial advisor’s expertise has a positive relationship with their trust in said advisor.
As you can see, the hypothesis is very specific in that it identifies the variables involved (expertise and trust), the parties involved (a customer and an advisor), as well as the expected relationship type (positive correlation). There’s no ambiguity or uncertainty about who or what is involved in the statement, and the expected outcome is clear.
Hypothesis Essential #2: Testability (Provability)
A hypothesis must be testable to qualify as a scientific hypothesis. If it’s not testable, it’s not a hypothesis. Testability means that you must be able to collect observable data in a scientifically rigorous fashion to assess whether it supports the hypothesis or not. In other words, there needs to be a way to prove the claim.
For example, considering the previous hypothesis, we could test this hypothesis by undertaking a study to assess whether people’s perceptions of an advisor’s competence correlate with their likelihood to trust that advisor. Generally, one would use quantitative research methods, covering a large sample (a group of people) to test such a hypothesis.
Now contrast that to the following statement:
Hypothesis 2: There are invisible, undetectable and unobservable forces all around us that influence our likelihood to trust a financial advisor.
In this case, the statement cannot be tested (because the forces are unobservable) and therefore, it’s not a sound hypothesis.
Hypothesis Essential #3: Falsifiability (Disprovability)
As we’ve seen, a scientific hypothesis needs to be testable (can be proven true), but that’s not enough. To be a useful hypothesis, it also needs to be falsifiable (disprovable). In other words, there needs to be some identifiable way to test whether a hypothesis is false. If there’s no way to assess whether a claim is false, it’s not a hypothesis.
For example, let’s look at this statement:
Hypothesis 3: Life exists on planets other than Earth.
Is this testable (provable)? Yes, you could send a space probe out that might find life on other planets. But is it falsifiable (disprovable)? Well, no.
If you were to send that same space probe out and it found no evidence or life on other planets, that would not disprove the hypothesis. To disprove the hypothesis, you’d need to visit every single planet in the universe (or observe every planet in a detailed way), which is simply not possible (at least right now!). Therefore, the statement is not disprovable and therefore, it’s not a hypothesis.
Defining A Research Hypothesis
You’re still with us? Great! Let’s recap and pin down a clear definition of a hypothesis.
A research hypothesis (or scientific hypothesis) is a statement about an expected relationship between variables, or explanation of an occurrence, that is clear, specific, testable and falsifiable.
So, when you write up hypotheses for your dissertation or thesis, make sure that they meet all these criteria. If you do, you’ll not only have rock-solid hypotheses but you’ll also ensure a clear focus for your entire research project.