Is it possible to prove a research hypothesis?
Hello! Back again for week 3! (isn’t the year just flying by!).
We’ve been given a wild card this week! I got to choose what I was going to discuss all by myself (well..I kinda choose it off a list of possible blog topics, but we won’t worry about that).
So, I have decided to tell you all about research hypothesis.
I’m sure the majority of you are aware what a research hypothesis is, but for those who don’t allow me to explain.
There are a few definitions of ‘research hypothesis’, but generally, this one seems good enough to illustrate my point: ‘A proposition about the nature of the world that makes predictions about the results of an experiment.’ (Taken from: www.sinauer.com/fmri2e/html/glossary.html ). So, I think that the key word here is ‘predictions’. You’re making a prediction about what you think will happen when you carry out your research.
OK…an example. Imagine that you want to research what colour swans are. Now, in your life, I’m sure that most, if not all, of you have only ever come across white swans and therefore may think that all swans are white. So, you make your research hypothesis that all swans are white. You go out, scour several places in search of swans, and you keep count of how many different coloured swans you find. At the end of your research, you take a look at your data, and sure enough all the swans you saw were white. Great, your research hypothesis was right, right?
Nope…you can’t say unequivocally that all swans are white, because you didn’t see all the swans in the world. Would you ever be able to be absolutely sure that you have seen all the swans in the world? Could you ever prove, for sure that your research hypothesis is correct? I’m afraid not. It’s never possible to prove a research hypothesis, but only to collect a lot of data that can strongly support it.
You can, however, disprove a research hypothesis. Thinking about the swans again, you could have spent years and years finding all the swans you could. Searching high and low in all the parks and ponds you could find, and STILL, you could have only found white swans! Someone could come along, and in an instant ruin your years of work by finding a black swan. Well, there we go….your research hypothesis was that all swans are white. You have tons and tons of data showing that swans are white, and this person goes and finds a black swan!! So, if this black swan exists, ALL swans can’t be white. Which means, unfortunately, your research hypothesis is wrong (and you’ve wasted years of your life looking at swans…good job this is hypothetical).
Not that I stole the swan story from a famous example or anything…but there is a book by Nassim Nicholas Taleb, called ‘The black swan: the impact of the highly improbable’ which discusses this in detail.
The idea of a black swan may have been highly improbable, but it’s never impossible (clearly as my picture above demonstrates). You can never say that a research hypothesis has been proven. Even if all the data in the world strongly supports it, that only makes it highly probable. We can never say that it is never impossible to find proof of the opposite.
To finish off, here’s a video of Nassim himself giving a talk on ‘black swans’. (I personally think I explained it better 😉 but there you go).
Thanks for coming again, next week I have another wild card…so who knows what’s in store for you!