What happens when a mistake is found in a published research article? Ask Science takes a look at scientific retractions and corrections.
In the poem "An Essay on Criticism," Alexander Pope wrote: “To err is Humane; to Forgive, Divine.”
In my latest episode, called Science Q&A, I made a mistake in answering a reader’s question about water beading up on his windshield. He asked:
“…the areas of the windshield outside the range of the windshield wipers coalesce into droplets on the window, while the area where the windshield wipers had wiped, the water didn't coalesce into droplets - it just ran off in a sheet.”
In response I stated:
“Generally, when water starts forming droplets like that, it's because it's sitting on some kind of hydrophobic surface which is preventing it from making hydrogen bonds.”
This explanation about water beading on the windshield was correct (see this more in-depth explanation about water beading and contact angles). However my hypothesis for why this was happening was completely wrong, because I misread the reader’s observations completely:
“…most likely the wipers are leaving a residue of rubber and/or teflon across the area of the windshield where they pass. This results in that portion of the window being partially hydrophobic, which causes the water to bead up, since it can't spread out very well.”
That might have been a great hypothesis if the water had been beading up in the center of the window, but since the question states that the water was beading up in the areas that the wipers weren’t passing, this hypothesis is complete bunk.
Fortunately, several Ask Science listeners were kind enough to write in and inform me of this error, including a listener named Dave who provided his own hypothesis, which sounds considerably more likely than mine:
“The explanation of water beading up on windshields is exactly backwards. The sheets of water are on the central wiped section, because the wipers have scraped off the hydrophobic sheen of oil and rubber that collects as we drive, the water beads up on the outside sections.”
Retractions and Corrections
As embarrassing as such a mistake can be, I’ve decided to turn this into an opportunity to talk about something that isn’t spoken about nearly enough in the scientific community: corrections and retractions.
As some of you might know, after a scientist has finished a particular batch of research, they typically write about it in a research paper. In that paper they discuss the research questions they were addressing, their hypothesis, the experiments they used to test their hypothesis, and the results of the experiments. At the end of each paper is usually a discussion section where the scientist gives their interpretation of the results and what they might mean for the future.
Once satisfied with their paper, they submit it to a scientific journal for publication. The journal editor will review the paper and then send a copy of it to two or three anonymous reviewers who will look over the paper to determine if the work has merit, if the experimental methods are sound, and if the conclusions reached are supported by the results of the experiment.