Researchers Say They Can ID You by the Way You Issue the Tissue in the Bathroom

Apparently, no-one pulls the paper quite like you do: introducing the TP ID.

Curiously, in 90 issues of these weekly newsletters, we’ve never written on toilet paper, as it were.

And that seems remiss (well, it does to us), since this bathroom staple plays such an essential role in helping you, uh, get to the bottom of your bacteria when collecting your sample to send to our lab.

Actually, looking into the whole area of toilet paper opened a rich seam of “stuff we didn’t know we didn’t know”, so expect at least one further newsletter on this subject.

But we begin today with a fabulous piece of research just published by scientists at Japan’s Kobe University, which looks into (and what better than to use the publication’s title itself?) a “personal identification system based on rotation of toilet rolls.”

In other words, they aimed to detect the identity of a toilet user by the way they pull the paper.

Now, perhaps, like us, your immediate question wasn’t “how?”, but “why?”.

And stay with us, because the whole story is actually pretty fascinating.

You see, the researchers began their investigation by recognizing that a lot of past work has been carried out on the potential of sensors in toilets to build up health information about users.

Technologists in Japan have definitely been big this area.

Consider, for example, the Japanese “Intelligence Toilet II,” launched in 2008.

(By the way, we thought it was a nice touch to include a Number Two in its name.)

It’s able to record and analyze data such as weight, blood pressure, body mass index, urinary sugar, and urinary temperature.

The manufacturers suggest that measuring pee temperature could be used to track and predict a woman’s menstrual cycle, among many other things.

Returning to toilet paper, however, the authors of the new research rightly point out that collecting this type of health data is only of use if data and dumper can be connected.

As they say, DNA analysis could do this with considerable precision (something like the science we use at uBiome, for example), but it would be slow and expensive.

Also pretty annoying to have an Illumina sequencer in your bathroom, not to mention its accompanying lab technician.

Inconvenient, you might say.

The objective of the study, therefore, was to devise a system that can identify who’s using the toilet in a bathroom with multiple users.

Global research conducted by Intel indicates that 70% of people are receptive to the idea of toilet sensors collecting personal health data, so the Japanese scientists built on this by asking a sample of individuals how they would, or would not, accept being identified in the bathroom.

Perhaps not surprisingly, the top you-gotta-be-kidding-me methods included facial recognition cameras and microphones (although they weren’t entirely forthcoming about the audio they might have chosen to collect).

Respondents were also uneasy about ID by fingerprint or duration of visit.

Of course, this last idea could be thrown wildly off course if someone chose to tackle War and Peace in the bathroom.

People were considerably keener on other ID suggestions, including someone’s flush handle technique, the distance between their heels and the toilet bowl (are you a tucker or a stretcher?), their door opening technique, or their toilet paper pulling technique.

And as we’ve already hinted, it was the latter that really caught the scientists’ interest.

They did briefly, and somewhat incongruously, consider the use of hand-waving as an ID method, but rejected this on the grounds that “in a lavatory, hand waving is an unnecessary action.”

Hand waving? We can only imagine they were thinking about people doing some kind of whiff-wafting.

And wouldn’t that really come under the heading of motion-detection?

Anyway, the basis of their focus on paper-pulling was that the researchers felt our methods in this area are more likely to be personalized, presumably since few of us have ever seen someone else engaged in this activity.

They didn’t say that many of us may have heard, rather than seen, bathroom neighbors dispensing the TP in ways that might sound, shall we say, exotic.

But we move on.

The solution was to fit wireless gyroscopes inside toilet paper rolls, then use Pootooth — sorry, Bluetooth — to capture data on the length of paper used, and the pulling velocity over time.

In this way they were able to record what they termed “multiple pulling actions,” when someone “pulls, tears, and uses” several times between entering and exiting the stall.

The study began with known participants using the bathroom with specially rigged toilet paper rolls. Then, after the system had been trained to identify “signature styles,” a second stage aimed to accurately identify who was who, without the benefit of other forms of identification.

So, how did they do?

Well, among a five person group in a research setting, they managed a creditable 83.9% level of accuracy.

However, as they moved from laboratory to lavatory, this fell to a slightly less impressive 69.2%.

Although, when you stop to think about it, it’s still pretty surprising to know that our personal paper pulling pattern is predictable enough to identify us, even approximately.

Before we close, a few fascinating facts.

There was apparently no significant difference in pulling action between men and women.

The number of pulling actions ranged from one to five.

In general, people used more than twice as much paper when they pooped as they did when they peed. (And before you jump to complete gender conclusions, although all females used paper after a pee, actually so did half the males, although only a small amount.)

This fabulous study has filled our full newsletter this week, but as we explained, opening the lid on the subject of toilet paper has brought an impressive amount of other content to the surface, so we’ll be back with more soon.

We’re excited about this.

You could even say we’re on a roll, in fact.

More reading

El dispensador de papel higiénico que te identifica por cómo sacas el papel y cuánto usas

Intelligence toilet II released

Japanese researchers spin up toilet paper gyroscopes for science

Personal identification system based on rotation of toilet paper (abstract)

Personal Identification System Based on Rotation of Toilet Paper Roll (video)

Personal Identification System Based on Rotation of Toilet Paper Rolls (paper)