Are you using your favorite word incorrectly? ("Parameter" or "variable"?)

Parameter. It’s a word that sounds impressive. And you can find it everywhere in the scientific literature. Scientists describe the parameters of a sample, list diagnostic parameters, and even calculate the parameters of various shapes. The word just feels good — don’t you feel like a serious scientist when you write “parameter” or dream of telling a plenary session of your peers that you have pinpointed the parameters of a problem?

But do you really, precisely know what parameter means in English? Have you noticed that the word parameter is used differently in high-impact journals and low-impact journals? Have you read what the Council of Biology Editors (now the Council of Science Editors) has written about the correct usage of “parameter” and “variable” (Council of Biology Editors 1994, 115)?

Before we go any further, take a moment to write down or tell yourself precisely what you think parameter means in English. (Hint: None of the examples above are correct.)

Now, if you’ve realized that you’re not entirely sure what parameter means, you’re not alone. Many scientists who are native speakers of English also misuse the word. Perhaps this is why many good journals, textbooks, manuals and style guides have tried to fix this problem.

For example, British Medical Journal has a good article that is freely available online. In this article, Altman and Bland (1999) explain that variables are things that you measure and record in a study and that vary from sample to sample. Parameters define theoretical models like the normal distribution that best fits your data. If you fit a line to your data, the slope and intercept of that line are parameters. If you adjust the values in some model to see what happens to the system that you are modeling, those values can also be called parameters.

But what if you have seen "parameter" used so often in a different way that you think that the word is used differently in your field? Well, you need to be aware that just because you have seen a word used in a peer-reviewed journal doesn’t mean that it was used correctly. There are many language errors in peer-reviewed journals. A good idea would be to check page 8 of the Wiley-Blackwell House Style Guide (Author unknown 2007). (Check here to see if Wiley-Blackwell publishes in your field.) And think about this: You’re a scientist. Do you want to write in way that sounds “science-y”, or do you want to write accurately and precisely?

REFERENCES:
Altman, Douglas G, and J Martin Bland. 1999. “Statistics notes Variables and parameters.” BMJ 1999;318:1667. Accessed October 16, 2014. doi: 10.1136/bmj.318.7199.1667
Author unknown. 2007. Wiley-Blackwell House Style Guide. Huddersfield: The Charlesworth Group.
Council of Biology Editors. 1994. Scientific Style and Format: The CBE Manual for Authors, Editors and Publishers, 6th Ed. Cambridge: Cambridge University Press.