Crime rates in the U.S. have been dropping since the 1990s. Criminologists and other experts sometimes call this the "great crime decline". Surveys show that most Americans believe that crime is increasing. I call this the "great crime disconnect" because for nearly two decades, public perceptions have been out of step with the evidence. Last week, I shared some of the data on crime rates and public perceptions. (I've since posted an updated version of that newsletter here.) This week I want to discuss why crime has been declining in the U.S., and what we can do to support this trend. In th ..read more

Interpreting data can be like listening to a 3-year-old talk about their day. At first it all makes sense, but then there's a giraffe, and chocolate sneakers, and other details that complicate the narrative until you're left wondering what really happened. Experts agree that crime in the U.S. has sharply declined since the 1990s, a phenomenon sometimes called the "great crime decline". However, the American public tends to believe crime has been increasing. That sounds like a pretty simple narrative. I call it the "great crime disconnect", because for much of the past two decades, public pe ..read more

Tell someone that our society has been profoundly transformed by statistics and they may nod politely, perhaps stifle a yawn. Then listen to what they want to talk about. You might find yourself discussing artificial intelligence, the latest Biden-Trump poll, Ozempic, or the chances of rain next week: Topics that wouldn't exist without statistics. We're all familiar with statistical data – poll results, student test scores, inflation trends, Caitlin Clark's field goal percentages, the probability of this, the rising tide of that. Less noticeable, for most people, is the role of statist ..read more

On my first day as a doctoral student at Cornell, I was intimidated by the brainy people as well as the brains. Take the Uris Hall elevator up to Cornell's psychology department, and the first thing you'll see when the doors open is a display case exhibiting eight jars, each containing a human brain. "Those are from students who failed," said the older classmate who was showing me around. It took me a moment to realize she was joking. What I was actually seeing were samples from the Wilder Brain Collection. Beginning in 1889, Cornell professor Burt Wilder began amassing a collection of hund ..read more

In March 2000, a man wearing nothing but a swimsuit and goggles set a Guinness World Record by swimming over 188 feet under ice. This was his second attempt. The first time he tried it, his corneas froze and he passed out. Welcome to the world of Wim Hof, aka the Iceman. According to Wikipedia, the only Guinness record that Mr. Hof still holds is for running a half marathon barefoot in ice and snow near Oulu, Finland in 2007 (2:16:34). However, Guinness now shows that Hof's record was broken last month by a man named Josef Šálek (1:50:42). Don't feel sorry for Mr. Hof that he lost his recor ..read more

Can happiness be measured? Can you become happier than you are now – and stay that way? According to a study published two weeks ago, the answer to both questions is yes. When I first heard about the study, I immediately recoiled. Happiness seems precious and mercurial and complicated. The thought of reducing it to a number made me unhappy. The thought of being told, again, how to become happier made me unhappy. Everyone from Aristotle to the life coach who passes out flyers at my gym has got advice, and if you want data, you don't have to look very hard. Yesterday, for instance, Gallup rel ..read more

People only use 10 percent of their brains. Every year, while sleeping, the average person swallows 8 spiders. And we should be walking 10,000 steps per day. These are examples of "zombie statistics" – figures that continue to be quoted after being repeatedly debunked. Like zombies, they prove hard to kill. Although the 10,000 step meme has been discredited more than once, a study published last week seems to have revived its credibility. At least that's what national news organizations and prominent health blogs are claiming. I want to talk about where the 10,000 step meme came from ..read more

New mental health treatments make an almost daily appearance in the news. On Tuesday, for instance, the New York Times reported on ibogaine, a psychedelic drug that offers new hope for treatment of opioid addiction. Yesterday, MedPage Today mentioned a new study showing that psilocybin significantly reduces generalized anxiety symptoms. Today, CNN discussed a separate study showing that a single dose of LSD also provides lasting relief from anxiety. As you can tell from these examples, psychedelics are getting a lot of attention, but they're not the only new giraffe in town. In this newslet ..read more

False accusations linger, even after being recognized as false. This is an example of what psychologists call the continued influence effect. Tell people that John McKenna accepted money illegally, then say wait, it's not true, a typo was responsible for the mistake, and people may still have doubts about McKenna's innocence. We needn't worry about John McKenna, because he's a fictional character from a 2016 study. But we do need to worry about continued influence effects when false accusations are made about real people and practices. For instance, research that questions the safety of exi ..read more

Environmental data tends to be pretty grim. I can't remember the last time I read something encouraging about climate change, microplastic debris, wildfires, etc. Last week though there was a barely noticed ray of hope. If you scrolled past the stories about Joe Biden's memory, Donald Trump's legal drama, and American's newest sweethearts (plus a football game, featuring Usher), you would've discovered, on the digital equivalent of the back page, that the EPA just announced a new standard for air quality. In this newsletter I want to describe why this announcement is good news. Sorry to say ..read more