Did Nicolas Guéguen Really Replicate the Cinnabon Effect?

Some years ago I blogged about a couple of scent-related field studies conducted by French academic researcher Nicolas Guéguen. In 2009, I wrote about a paper of his I had just come across, published in Psychological Reports back in 2001. In “Effect of a perfume on prosocial behavior of pedestrians,” Guéguen found that people were more helpful to a young woman who “accidently” dropped an item when she was wearing perfume, compared to when she was not wearing scent. I thought the paper was worth mentioning because it described a theory-free, empirical approach that could shed light on the natural history of perfume use.

Three years later, in a post called “The Cinnabon Effect Confirmed,” I wrote about another of Guéguen’s studies. This one, published in the Journal of Social Psychology, was titled “The sweet smell of . . . implicit helping: effects of pleasant ambient fragrance on spontaneous help in shopping malls.” The original Cinnabon Effect study was discovered in 1997 by social psychologist Robert Baron who found that shoppers in a mall were more helpful to a stranger when approached next to a pleasant-smelling retail shop (e.g., Cinnabon) rather than an unscented one (e.g., Banana Republic). In his new paper, Guéguen found similar results in a French mall, and extended the paradigm to include male as well as female “strangers.” I wrote approvingly that “Guéguen has confirmed the Cinnabon Effect and extended it to spontaneous acts of kindness.”

I recently became aware that Guéguen’s “sweet smell of” study has been the object of some impressive data sleuthing by Nicholas Brown and James Heathers. A new post on the excellent Retraction Watch website updates the story. In a nutshell, the pair claims that a bunch of papers by Guéguen don’t pass the smell test. The reasons for their skepticism are procedural and statistical. Guéguen is a prolific author yet one with no collaborators, and he may, according to Brown and Heathers, have skirted ethical requirements. Disturbingly, statistical patterns in his underlying data seem consistently fishy. The original B&H posts can be found here and here.

It’s important to note that Brown and Heathers do not claim outright that Guéguen’s studies are fraudulent.

We have not made, and do not make, any specific allegations of fraud, nor are any implied. The initial document that we released is entitled “A commentary on some articles by Dr. Nicolas Guéguen” and details a long series of inconsistencies in research methods, procedures, and data. The words “fraud” and “misconduct” do not appear in this document, nor in any of our communications with the people who helped with the investigation. We restrict ourselves to pointing out that results are “implausible” (p. 2) or that scenarios are “unlikely [to] be enacted practice” (p. 31).

You can download their detailed fifty-two page critique here and judge it for yourself. If you’re less hardcore, this Ars Technica piece covers the story nicely.

I think the points raised by Brown and Heathers are compelling and cast serious doubt on some, if not all, of Guéguen’s work. Accordingly, I’m putting a metaphorical asterisk on the two studies I cited, and flagging this action on my previous blog posts. Data integrity and transparency are core to the scientific endeavor, and when serious doubts are raised they need to be acknowledged.