The OSM global copy receives up to 5M changes every day, which means our local copy would quickly become outdated if we didn’t regularly update it. To reduce the risk of bad edits, whether intentional (vandalism) or unintentional, we don’t update our local copy directly. Instead, changes between the 2 versions are reviewed and accepted into the local copy. This all needs to be done on a regular cadence, or the growing difference between the global and local versions will require significant time and effort to catch up. We developed 2 new tools to help us keep pace: Logical changesets (LoChas) and our new machine-augmented automatic review system (MaRS).
LoChas break OSM changesets into individual CRUD operations and then cluster them for more efficient human review. MaRS uses a blend of heuristics and machine learning (ML) techniques to automate evaluation of LoChas that don’t require a further nuanced review. The ultimate goal of these tools is to create a funnel where machine-augmented techniques reduce the workload that requires human intervention.
Month: September 2019
Mind scaffolding
Language is the scaffold of the mind
The lack of language affects even functions that do not seem to be intrinsically “linguistic,” such as math. Developmental research shows that keeping track of exact numbers above 4 requires knowing the words for these numbers. Imagine trying to tell the difference between 7 apples and 8 apples. The task becomes almost impossible if you can’t count them—and you can’t count them if you never learn that “7” is followed by “8.” As a result of this language-number interdependency, many deaf children in industrialized societies fall behind in math, precisely because they did not learn to count early on
What do executives do?
An executive with 8k indirect reports and 2000 hours of work in a year can afford to spend, at most, 15 minutes per year per person in their reporting hierarchy… even if they work on nothing else. That job seems impossible. How can anyone make any important decision in a company that large? They will always be the least informed person in the room, no matter what the topic. The job of an executive is: to define and enforce culture and values for their whole organization, and to ratify good decisions. That’s all. Not to decide. Not to break ties. Not to set strategy. Not to be the expert on every, or any topic. Just to sit in the room while the right people make good decisions in alignment with their values. And if they do, to endorse it. And if they don’t, to send them back to try again.
Skateboard Tricks
AR Tabletop
Tilt5’s approach to AR is quite different from the others you’ve seen. The glasses require you place an inexpensive sheet of retroreflector on a surface (table, wall or stand) and it can display anything in 3D where that surface is. Real world objects can then be placed on the table and mix with the virtual ones. This may seem quite limiting, it doesn’t try to paint things on top of the arbitrary world like Magic Leap, but it has some big advantages because of this method:
Atlas gymnastics routine
Atlas uses its whole body — legs, arms, torso — to perform a sequence of dynamic maneuvers that form a gymnastic routine. We created the maneuvers using new techniques that streamline the development process. First, an optimization algorithm transforms high-level descriptions of each maneuver into dynamically-feasible reference motions. Then Atlas tracks the motions using a model predictive controller that smoothly blends from one maneuver to the next. Using this approach, we developed the routine significantly faster than previous Atlas routines, with a performance success rate of 80%.
Space Dust Ice Age
466m years ago, there was a very, very large asteroid impact. But, despite what you’re thinking, it actually helped life on Earth be fruitful and multiply. And that’s because the asteroid impact wasn’t on Earth. It was in the inner asteroid belt. A new paper points the accusatory finger at… dust. A lot of it, blasted outward when 2 big asteroids collided. This dust made its way to Earth, blocked a significant fraction of warming sunlight, started an ice age, and that put stress on marine environments which caused a burst of evolutionary diversity.
Unix at 50
Maybe its pervasiveness has long obscured its origins. But Unix, the operating system that in 1 derivative or another powers nearly all smartphones sold worldwide, was born 50 years ago from the failure of an ambitious project that involved titans like Bell Labs, GE, and MIT. Largely the brainchild of a few programmers at Bell Labs, the unlikely story of Unix begins with a meeting on the top floor of an otherwise unremarkable annex at the sprawling Bell Labs complex in Murray Hill, New Jersey.
Biased Energy Discussion
There seems to be systemic racism or stupidity in the analysis of the world energy situation. Whenever there is a global analysis of the cost of different energy sources, there is a focus on the cost of energy projects in the USA and Western Europe. However, 80-90% of the actual new energy construction action is in Asia and the Middle East. Over 80% of the reactors under construction being built by China, India, Russia and South Korea are doing fine. They are 33-50% of the cost and usually are complete in 4-6 years.
History of light beer
Chemist Joseph Owades, working for Rheingold Breweries in New York City, broke apart beer’s long carbohydrate chains to produce the world’s first “light” beer in 1967. Marketed nearly exclusively to diabetics, it went nowhere. Thus, the development of “light” beer came with a commensurate marketing challenge: how to persuade the traditionally masculine beer-drinking audience to try a lower-calorie version of their favorite brew.
Gregor J. Rothfuss 