A subjective discussion of the meanings of “subjective” and “objective”
Scientists are objective. Personal bias is not acceptable and interpretation that is subject to the observer is frowned upon.
The above statement is the ideal to which we presumably strive to attain as scientists. The reality that we construct in our research is independent of the person doing the research. So, when someone performs some kind of “subjective” research — such as constructing a classification scheme or hand-drawing a weather map to be consistent with the observations — we generally view that as inferior to a classification scheme that was produced by an automated algorithm or an objective analysis of the weather map performed using a Barnes analysis, for example.
I am advocating that we avoid the terms “subjective” and “objective” when used in this manner. Saying our method is subjective implies it is not “objective” or reproducible. Likewise, so-called objective criteria are often anything but. As I heard Chuck Doswell repeat numerous times, thresholds for objective criteria need to be determined, and they are usually subjectively determined by the creator of the method.
Rather than “subjective” and “objective”, I prefer the terms “manual” and “automated”, respectively. For more on this distinction, please read section 18.2 of Eloquent Science: A Practical Guide to Becoming a Better Writer, Speaker and Scientist.
So, if you are using a manual approach in your study, how do you avoid the charge that your method is “subjective” and not reproducible? Easy. Be as specific as you can in how you collect your data. Determine quantitative criteria for your scheme, if possible. Don’t choose overlapping categories, but distinct separable categories. And, most important of all, describe very clearly and precisely in the manuscript how you arrived at your classification scheme. The more detail that you use, the less you will be accused of a “subjective” (i.e. not reproducible) study.
What do you think?
(Image from http://stephaniemcmillan.org)