There’s an urban legend that there are as many rats as people in NYC. Jonathan Auerbach, a student at Columbia University, did some research and puts the number of rats at far fewer.
Mr. Auerbach, who was a fiscal analyst for the City Council and for the New York City Labor Market Information Service at the City University of New York before enrolling at Columbia, acknowledged in his paper that conducting a rat census posed significant challenges for a statistician. “Animals are terrible survey respondents,” he noted dryly.
He faced other methodological problems. He could not capture a large number of rats, mark them for identification purposes, release them, capture a second batch and count the number of marked rats in that batch. “Unfortunately,” he wrote, the health department “is unlikely to approve a large-scale rat-releasing experiment (I know, because I asked).”
The main flaw I see in his research is that not every sighting is reported.
Jawbone looked at the data from Up devices from June 1, 2013 through June 1, 2014, organized by city.
The movement and sleep patterns of a city tell an amazing story about its culture and people. How active is a city? When do they go to bed on average, and how much do they sleep? How stark are the differences between weekends and weekdays? What events brought people together and significantly impacted the health of a city? Each pattern forms a distinct “thumbprint” for the city, the unique way its citizens live their lives. To an untrained eye, these images may just look like the abstract brush strokes of a Rothko painting. To a data scientist, however, these graphics richly detail the routines — and occasional abnormalities — of city denizens.
The main problem with data like this is that it represents a subset of a subset of people in the city: people who wear fitness trackers, and of those, people who wear a Jawbone Up. This is not a very representative sampling of people. By definition, people who wear fitness trackers are probably more concerned with their health and as such would, on average, go to bed earlier, get up earlier, and be more active than non-fitness tracker wearing people. The only data this really shows us is how Jawbone Up users in one city compare to Jawbone Up users in another city.
The Wall Street Journal brings us news that seven hours may be the optimal amount of sleep for a healthy adult.
“The lowest mortality and morbidity is with seven hours,” said Shawn Youngstedt, a professor in the College of Nursing and Health Innovation at Arizona State University Phoenix. “Eight hours or more has consistently been shown to be hazardous,” says Dr. Youngstedt, who researches the effects of oversleeping.
However, the article cautions that sleep time and health may be associated but that oversleeping may not be a causation of ill health.
“I don’t think you can overdose on healthy sleep. When you get enough sleep your body will wake you up,” said Safwan Badr, chief of the division of pulmonary, critical care and sleep medicine at Wayne State University School of Medicine in Detroit.
I tend to wake up after about 6.5 to 7.5 hours of sleep. That is unless my sunburned foot wakes me up first…ouch!
There’s some big soccer tournament going on and one of the players bit another one in the middle of the game. Apparently, this is not the first time he’s done that, which lead Ian Steadman to crunch some numbers and realize that you are more likely to be bitten by Luis Suarez than by a shark.
We can therefore conclude that Luis Suarez has roughly a one in 2,000 chance of biting any individual opposition player. For comparison, the following things are less likely than being bitten by Luis Suarez:
Many people pointed out that the numbers he was using were not exactly fair, so he recalculated using waters where sharks are more likely to be, leading him to this conclusion:
This means that Luis Suarez is almost exactly as likely to bite someone as a shark is in the very definition of “shark-infested” waters.
I just found out that “USMNT” stands for “U.S. Men’s National Team” and not “U.S. Mutant Ninja Turtles”.
You know that thing where if you tap the top of someone else’s bottle of beer with the bottom of your bottle, their beer foams all over the place? Yeah, scientists have figured out why that happens.
After a sudden bump against a bottle’s mouth, back and forth movement of compression and expansion waves will cause bubbles to appear and quickly collapse.
The team’s investigation of beer bottle-fluid interactions demonstrated that the cavitation-induced break-up of larger ‘mother’ bubbles creates clouds of very small carbonic gas ‘daughter bubbles’ which grow and expand much faster than the larger mother-bubbles from which they split. The rapid expansion of these daughter bubbles gives the foam buoyancy.
Again, I am glad that scientists are spending their time doing important work.
Researchers from the University of Vienna, Austria, and the Nova Southeastern University and SUNY College at Oneonta may have discovered why we yawn, and why it may be contagious.
While most research on contagious yawning emphasizes the influence of interpersonal and emotional-cognitive variables on its expression, this report adds to accumulating research suggesting that the underlying mechanism for yawning, both spontaneous and contagious forms, is involved in regulating brain temperature. In turn, the cooling of the brain functions to improve arousal and mental efficiency. The authors of this study suggest that the spreading of this behavior via contagious yawning could therefore function to enhance overall group vigilance.
It’s currently 4:40am and I’ve been yawning like crazy. I tend to think that has more to being tired than warm, but what do I know?
Nate Silver at FiveThrityEight looks at when U.S. cities get to work, and New York is the latest.
These cities break down into three rough categories. First are those like New York, San Francisco and Boston, which are home to a lot of young, creative professionals. Next are college towns such as Ithaca, N.Y. (Cornell University); Lawrence, Kan. (the University of Kansas); and Logan, Utah (Utah State University). Finally are cities such as Atlantic City, N.J., Orlando, Fla., and Miami, whose economies are associated with recreation, tourism and gambling. A quarter of the workforce in Atlantic City doesn’t begin its workday until 11:26 a.m. or after.
I like how Nate claims to not be a morning person, but the article was posted at 7:01am. I’m going to assume it was a scheduled post. For the record, my work day officially starts at 9:30am, and if I do a quick shower and half a shave, I can get out of bed at 8:00am and be at work with time to spare — assuming the MTA has the 4, 5, & 6 trains running well.
A new study has found that humans may be able to distinguish up to 1 trillion different odors.
To find out how many odors we can distinguish, researchers asked 26 participants to put their noses to the test. During each experiment, study participants were asked to smell the contents of three vials that the scientists had mixed themselves using 128 different odor molecules. Two of the vials contained the same mixture, while one did not. The participants’ task was to identify the odd mixture. Then, using the statistics obtained during the tests, the researchers were able to determine that people can distinguish two odors when their components differ by more than half.
Based on the smells of the homeless in the NYC subway, I’m guessing we can perceive much more than 1 trillion.
Researchers believe that dogs became domesticated much earlier than originally thought.
The authors concluded that dog domestication most likely occurred in Ice Age Europe, between 18,800 and 32,100 years ago — much earlier, and much farther north, than previously believed.
“The initial interactions were probably at arm’s length, as these were large, aggressive carnivores,” said senior study author Robert Wayne, an evolutionary biology professor at UCLA. “Eventually though, wolves entered the human niche. … Maybe they even assisted humans in locating prey, or deterred other carnivores from interfering with the hunting activities of humans.”
Of course, there are those who disagree with the findings. What I want to know is, when did dogs become cute?
Researchers find that high-fat/high-sugar foods like Oreos may be as addictive as cocaine or morphine.
Researchers also looked in the nucleus accumbens, or the brain’s pleasure center, and measured how much c-Fos, a protein marker that signals brain neuron activation, was expressed. In simple terms, they were looking at how many cells were turned on in response to the drugs or Oreos.
The researchers saw that Oreos activated significantly more neurons than cocaine or morphine.
I had a pack of Oreos yesterday and was extremely disappointed when I opened the pack, so I can see how valid this research may be.