Links for November 2017

Just heard about this story showing that the AZ governor means business:

Three weeks into his new job as Arizona’s governor, Doug Ducey made a move that won over Silicon Valley and paved the way for his state to become a driverless car utopia.

It was January 2015 and the Phoenix area was about to host the Super Bowl. Mr. Ducey learned that a local regulator was planning a sting on Lyft and Uber drivers to shut down the ride-hailing services for operating illegally. Mr. Ducey, a Republican who was the former chief executive of the ice cream chain Cold Stone Creamery, was furious.

“It was the exact opposite message we should have been sending,” Mr. Ducey said in an interview. “We needed our message to Uber, Lyft and other entrepreneurs in Silicon Valley to be that Arizona was open to new ideas.” If the state had a slogan, he added, it would include the words “open for business.”

Mr. Ducey fired the regulator who hatched the idea of going after ride-hailing drivers and shut down the entire agency, the Department of Weights and Measures. By April 2015, Arizona had legalized ride-sharing.

This (violent) scene from the movie Unbroken depicts a B-24 Liberator defending itself using mounted machine guns during a bombing mission.
https://www.youtube.com/watch?v=8lI4ZxM8QNg

“If you have any kind of prejudice or concern that somehow their system and their educational system is not going to produce the kind of people that I’m talking about, you’re wrong.”

“We’re not stuck,” he said. “It doesn’t feel like we’re on the verge of getting it all sorted, but I know more each day than I did the day before – and so presumably we’re getting somewhere.”

If you’re reading this, you will probably be dead in 6 decades or less, maybe much less. And if you’re over 25, your brain function has probably peaked. Time is running out.

Let’s call the game “relay programming”. To run the game, the game master picks a challenging programming problem. For concreteness, let’s say Project Euler problem 62:

“…41063625 is the smallest cube which has exactly three permutations of its digits which are also cube. Find the smallest cube for which exactly five permutations of its digits are cube.”

(I chose this problem because I don’t know how to solve it, and I don’t know what strategy I’d use to solve it, and I don’t think I’d make that much progress in ten minutes, but I’m 75% confident I’d solve it in five hours of work, based on its difficulty as rated on the Project Euler website.)

This game is called a relay because it is played with a team of people, each of whom is only allowed ten minutes to contribute. The first player is sent an email which contains the problem; before ten minutes is up they must reply with the email that they want to be sent to the second player. The game continues with fresh players until the task is solved.

So every player has ten minutes to make as much progress as possible. One possible thing that the first player could do over those ten minutes is think about how to decompose the problem…

Relatedly, it is interesting that the concept of a Political Officer is associated strongly with the Soviet Union even though the general idea — an integration of high-ranking officers designed to maintain civilian control of the military — could arguably be useful to democracies.

The DARPA Spectrum Collaboration Challenge (SC2) is the first-of-its-kind collaborative machine-learning competition to overcome scarcity in the radio frequency (RF) spectrum. Today, spectrum is managed by dividing it into rigid, exclusively licensed bands. This human-driven process is not adaptive to the dynamics of supply and demand, and thus cannot exploit the full potential capacity of the spectrum. In SC2, competitors will reimagine a new, more efficient wireless paradigm in which radio networks autonomously collaborate to dynamically determine how the spectrum should be used moment to moment.

The team whose radio design most reliably achieves successful communication in the presence of other competing radios could win as much as $3,500,000.

(H/t aresant.)

The Wirecutter makes money with referral links through retailers (mostly Amazon) rather than manufacturers. Arguably, it is evidence that advertisement-based websites have fundamental equilibrium limitations, and that retailer oligopolies can have surprising benefits. My chief complaint is that the Wirecutter is geared toward folks less stingy than myself, likely induced by their incentive to get commission on large purchases.

The processor specifically designed for machine learning is, of course, Google’s “tensor processing unit“.

Primary care doctors (eg family, internal, and emergency medicine) will benefit most from affordable ultrasound. We are learning that it’s a powerful diagnostic tool when used along side the physical exam. Some zealots have equated bedside ultrasound to be the biggest advancement to medicine since antibiotics. This notion I feel is exaggerated, but— it taps into the underlying excitement in the medical community for bedside ultrasound…

Patient came in with all the symptoms and findings of a stroke— altered mental status, inability to move their left arm. Before giving the treatment for a stroke, a potent blood thinner called tPA, the doctor decided to do an informal ultrasound of the patients heart. He found the patient had a massive dissection of their aorta. The patient wasn’t getting adequate blood flow to their arm or brain. Had the patient been given tPA they most likely would have died. A quick bedside ultrasound revealed a difficult diagnosis and saved the patients life.

these procedures resulted in nearly 73,000 babies — 1.6 percent of all U.S. births. The rate is even higher in some countries, including Japan (5 percent) and Denmark (10 percent).

(H/t Gwern.)

Why is drug resistance common and vaccine resistance rare? Drugs and vaccines both impose substantial pressure on pathogen populations to evolve resistance and indeed, drug resistance typically emerges soon after the introduction of a drug. But vaccine resistance has only rarely emerged. Using well-established principles of population genetics and evolutionary ecology, we argue that two key differences between vaccines and drugs explain why vaccines have so far proved more robust against evolution than drugs. First, vaccines tend to work prophylactically while drugs tend to work therapeutically. Second, vaccines tend to induce immune responses against multiple targets on a pathogen while drugs tend to target very few. Consequently, pathogen populations generate less variation for vaccine resistance than they do for drug resistance, and selection has fewer opportunities to act on that variation. When vaccine resistance has evolved, these generalities have been violated. With careful forethought, it may be possible to identify vaccines at risk of failure even before they are introduced.

To oversimplify, property rights are often said to be good against the world, while contract rights are good against specific others.

A share of stock is itself a set of contractual rights, but the record owner has a property right in the share (and often a physical certificate). It doesn’t matter if someone takes your share or inadvertently/accidentally sells it to an innocent buyer. It’s still yours and you have a better claim to it than any buyer or later holder.

But a beneficial owner of a share held in “street name” has only a contractual right to his shares–essentially a promise from his broker that the broker will have at least [x] shares for him (note this means he does not have a claim to any specific or identifiable shares and his broker surely holds many times more since they’ll have many other clients). And on top of that, his broker has an account with DTC that involves a second layer of contractual rights to the stock–essentially a promise from DTC to the broker that DTC will have at least [x] shares for the broker (again not specific or identifiable shares and DTC certainly has many times more shares since DTC holds nearly all shares held in “street name”)

If your broker or DTC accidentally or inadvertently disposes of too many shares (and this can happen surprisingly often) you only have recourse against your broker or DTC. The agreements between [you and your broker] and [your broker and DTC] do not bind the new owner of the shares, who has no obligation under those agreements and, as a bona fide buyer + current holder, also has a better claim to the shares than you do.

If that wasn’t specific enough, here’s a very detailed summary and analysis of the current stock ownership structure and mechanics:

http://scholarship.law.upenn.edu/cgi/viewcontent.cgi?article=1163&context=faculty_scholarship