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In the immortal words of Jay-Z, allow me to reintroduce myself…
markfontana.substack.com/p/w…
Mark Alan Fontana retweeted
For six months, Google Maps sent a slice of drivers in ten American cities down deliberately slower routes.
About 30 seconds slower on average, and under 2% of trips were touched. The experiment ran on roughly 100 of the most congested road segments in each city, switching on and off day by day so each city acted as its own control. The results are out now in Nature Cities, from Google Research with collaborators at Berkeley and Stanford.
The reasoning behind it is old and slightly counterintuitive. Every navigation app does the same thing: it finds you the fastest route right now, for you alone. When millions of phones do that at once they all pour onto the same handful of arteries, and those arteries stop being fast. Transport economists have been writing about the gap between what's good for one driver and what's good for the network since the 1950s. Nobody had tested a fix at city scale with real drivers, because you'd need to steer routing for a large share of a city's traffic, and about three companies on Earth are in that position.
So Google put a penalty on the worst segments during their worst hours, which nudged the routing engine towards alternatives of similar road class and comparable travel time, then measured what happened across the whole network on weekdays between 7am and 8pm.
On the targeted segments, traffic moved roughly 2% faster in the median city. Los Angeles got 4.56%, Atlanta 3.30%. Fuel burn on those stretches dropped between 0.5% and 1%. Across every road that saw a change in traffic, which covers around 80% of each city's driving, speeds rose 0.35%, reaching 0.5% during the morning and evening peaks. Total travel time on affected trips fell 0.69%. Their Bayesian model put the probability that the speed effect was genuinely positive at 99.8%.
That adds up to more than 1,000 tonnes of CO2-equivalent saved per year, per city, in most of the places studied. Cars and vans account for around 10% of global carbon emissions, and the average driver spends about 2.6 years of their life behind the wheel, so a fraction of a percent across an entire road network is a serious amount of fuel.
Per driver, the saving comes to about 0.25% of an average journey, roughly one fortieth of the normal day-to-day wobble in how long the same commute takes. Nobody in those ten cities noticed anything, in either direction, including the people sent the long way round.
The authors are careful about what they haven't shown. They measured the immediate effect, not what happens once drivers work out the freed-up route is quicker and pile back onto it, which is the standard way road improvements get eaten. Their penalty scheme was deliberately crude, so the ceiling on the approach is unknown. And the underlying Google Maps data is commercially confidential, so nobody outside can check the numbers.
The finding sitting underneath all this is that a private company's routing algorithm has become a piece of transport infrastructure, tunable in the way a traffic light or a congestion charge is tunable. The obvious follow-up experiments are the ones a city government would want to run, not the ones a mapping company would.
link to full article: nature.com/articles/s44284-0…
Mark Alan Fontana retweeted
Can machine learning predict who will get injured during marathon training? 🤖🏃♀️🤕
Our latest study, published this week in @PMRJournal in collaboration with @Strava and @nyrr, investigates this question in runners training for the NYC Marathon.
onlinelibrary.wiley.com/doi/… 🔓
Mark Alan Fontana retweeted
🚨 NEW: Netflix secretly recorded an interview with Dr. Jane Goodall in March, set to air only after her death.
In it, she says she wishes Trump and Elon Musk could be blasted into space… and closes with:
“Don’t lose hope.”
Now that’s a final message.
Mark Alan Fontana retweeted
Firing the BLS Commissioner — the wonk in charge of the statisticians who track economic reality — is an authoritarian four alarm fire.
It will also backfire: You can't bend economic reality, but you can break the trust of markets. And biased data yields worse policy.
Mark Alan Fontana retweeted
Ice crystals in Earth’s atmosphere sometimes align just right to create various striking visual effects, from a halo around the moon, to bright spots called sun dogs on either side of the sun in a winter sky, or a rainbowed pillar, called a crown flash, above a storm cloud.
Similar phenomena can appear in the skies over some exoplanets of the “hot Jupiter” variety, a common type of gaseous giant that always orbits close to its host star, Cornell astronomers have found. On WASP 17b, a hot Jupiter exoplanet, 10,000 mile per hour winds could align particles in clouds made of quartz and other crystalline mineral aerosols, creating conditions in which polarizing dust could interact with starlight in the same way aligned ice crystals interact with sunlight on Earth.
“Just like the alignment of ice crystals in Earth’s atmosphere produces observable phenomena, we can observe the alignment of silicate crystals in hot Jupiter exoplanets,” said Elijah Mullens, M.S. ’24, astronomy doctoral student in @CornellCAS and co-author of the study.
More at news.cornell.edu/stories/202….

ALT A sun dog and 22 degree halo appearing over Winnipeg, Canada. Sun dogs and other visual effects occur when icy crystals in Earth’s atmosphere align in certain ways; Cornell astronomers predict that similar effects can appear when starlight interacts with quartz crystals in exoplanet atmospheres.
Can we start calling a spade a spade? This sort of government-sponsored violence for the sake of quelling basic rights of co-equal branches (let alone that of average citizens) and advancing their own political ends is *FASCISM*
BREAKING: California Democratic Senator @AlexPadilla4CA just crashed DHS Secretary Noem’s press conference in LA and was forcibly removed.
My team’s first foray into AI-generated synthetic medical imaging. Promising given pathologies generated in the synthetic MRIs are usually accurate (high ppv), but not good enough for clinical care given the synthetic MRIs often miss pathologies (low sensitivity) @HSpecialSurgery
"AI-Generated Synthetic STIR of the Lumbar Spine from T1 and T2 MRI Sequences Trained with Open-Source Algorithms"
doi.org/10.3174/ajnr.A8512
@metamaf @The_ASSR @LeviChazen #EditorsChoice
Mark Alan Fontana retweeted
OMG they applied their stupid fucking formula incorrectly?!?
aei.org/economics/president-…
Zero trade balances as a policy goal… Ricardo is rolling in his grave
I stand corrected. The formula is not deficit/imports. The formula is surplus/(imports * ε * φ), where ε = -4 and φ = 0.25. That happens to equal deficits/imports.
ustr.gov/issue-areas/recipro…
via @ericadyork
Mark Alan Fontana retweeted
These guys inherited one of the most functional state apparatus in the history of the world and they are inhabiting it like a crack house.
theatlantic.com/politics/arc…
Mark Alan Fontana retweeted
FYI, Zelensky’s semi-military official attire represents a very, very important aspect of life in Ukraine right now—tactical clothing and various gear that is worn by everyone who has any connection to the war and combat operations.
Over the years of war, an entire subculture of tactical clothing has developed in Ukraine, along with popular domestic brands such as M-Tac or Talan, and at times, we have as many military surplus stores as shawarma stands (often owned and run by veterans).
Pants, T-shirts with Velcro patches for insignia, jackets with multiple pockets, tactical backpacks, caps, knives, boots—demi-season, summer, winter—ballistic glasses, gloves, multitools, all kinds of accessories for body armor, weapons, and gear. Black, gray, olive, navy, coyote, every possible camouflage pattern, and everything else.
You could go on forever.
The culture of military patches, both official and unofficial, where there’s space for the wildest imagination and exercises in wit, is a whole separate topic, worthy of thick books.
Many soldiers are constantly buying extra gear to supplement or replace the standard-issue military clothing and equipment provided by the state. Many newly mobilized recruits rush to military stores and buy everything they see, even if they are drafted as accountants, only to later realize they have no idea what to do with piles of tactical gloves and night vision devices.
Tactical clothing is also worn by journalists, demobilized veterans, instructors, volunteers—many people involved in the war, supporting the army, and working in the combat zone.
Yours truly, for example, has not parted for years—from the days of the "ATO" in Donbas to the battle for Bakhmut—with my black "police-style" jacket worn under body armor, as well as black tactical pants, a backpack, and M-Tac coyote boots. They were with me even in the rainy equatorial forests of East Africa.
It’s not just incredibly practical, it’s also a statement—I'm not a soldier, but I am part of the common cause of defending the country from the aggressor, of saving our nation and our way of life, and I am making my contribution.
Here’s an example: at the start of the battle for Kyiv, when Russian troops were already storming the outskirts of the capital, many who remained in the city were preparing for bloody urban combat. And many were stocking up on tactical clothing and gear (just because you're in a battle doesn't mean you shouldn't look fabulous and well-equipped, right?).
I was among them—and when I arrived at one of the major tactical stores still operating in the city, I was taken aback because I found a line stretching half a kilometer long.
This is an important aspect of life in Ukraine, visible every day in cities across the country. It’s also important to buy from Ukrainian brands, supporting veteran-owned businesses, as well as to wear national symbols—such as the Tryzub of Prince Volodymyr the Great.
One crucial rule—civilians (unless they are demobilized veterans) have no moral right to buy and wear camouflage clothing, whether it’s Multicam or our Ukrainian military patterns like the army’s "pixel." In this community, it is considered immoral and unacceptable. Camouflage is a mark of honor for a soldier. Want to wear it? Take the oath and join the military.
But if, for example, a civilian involved in the war effort wears tactical clothing in black, gray, dark blue, olive, or beige—there’s no issue. It’s practical, and it fits the times.
This is exactly what Zelensky does when he meets world leaders in front of the cameras in semi-military tactical attire. He represents a fighting Ukraine, where millions of people are not just serving in the armed forces but also contributing to the country’s defense for the sake of a common future in their homeland.
And Zelensky does it the right way—he deliberately avoids wearing an official military uniform or camouflage, which other politicians have shamelessly and absurdly used for self-promotion.
Yes, he is the Commander-in-Chief, but he is not a soldier, and even he does not have the moral right to wear camouflage, which is sacred, because it is in that uniform that Ukrainian soldiers shed their blood for our country and heroically fight against one of the largest and most ruthless armies in history.
All of this is far beyond and far greater than those petty, sneering giggles "Do you even have a suit?"
Mark Alan Fontana retweeted
Staff at the World Trade Center Health Program have been rehired and research funding has been restored.
I'm grateful Republicans joined Democrats to call out these outrageous cuts, and I look forward to working together to permanently protect the program.
Mark Alan Fontana retweeted
Upon receiving the news that four of the City's Deputy Mayors have submitted their resignations, I sent the following letter to @nycmayor.
If Mayor Adams cannot provide a contingency plan to the 8 million New Yorkers who rely on City services to function, I will seek to convene a meeting of the Inability Committee.
comptroller.nyc.gov/newsroom…
Mark Alan Fontana retweeted
Collaborative and comparative research begins with agreeing on what data to collect. Excited to share our Delphi consensus from the RHC on health history and injury surveillance in runners and other endurance event participants 👟🔓 @BJSM_BMJ @TheAMSSM
bjsm.bmj.com/content/early/2…
Mark Alan Fontana retweeted
Prevention requires bold & forward-thinking investments. My OpEd on why letting funding lapse for @AllofUsResearch would be a step backwards statnews.com/2024/09/03/all-… @statnews































