Hacker News Reader

lacksconfidenceon Plugin hybrids in new emissions scandal: test show higher pollution than claimed

Why compare it to the Mk1? How does the modern gas version compare to the Mk1?

lacksconfidenceon Wikimedia is moving to Gitlab

At least the way our installation works we don't push to changes/nnnn/12, rather changes are pushed to refs/for/{branch} (often refs/for/master). This endpoint isn't an actual branch. It triggers gerrit to look up the nnnn for the Change-Id in the commit message and create the appropriate branch for the next patch set.

lacksconfidenceon Wikimedia is moving to Gitlab

It's not a force push under the hood. Under the hood a new branch is created (first patch set is /refs/changes/nnnn/0, second is /refs/changes/nnnn/1, etc.). From the end user perspective the result is quite plausibly similar to force push.

lacksconfidenceon Ultralight lithium-sulfur batteries for electric airplanes

One confounding factor is parking arrangements. If you have a garage then a wall socket is reasonable, but for many years the only place i could park a car was somewhere on the street, hopefully within 100m of my address. In that situation commercial charge points (hopefully near my employer, if lucky) would be the only reasonable charge point.

lacksconfidenceon A random sampling of internet service prices around the world

Could use another metric, "number of big macs" or whatever to help compare what the amount of $ is worth in the local market.

lacksconfidenceon Pandemic speeds largest test yet of universal basic income

To me success looks like canceling the mountain of other welfare programs and removing vast inefficiencies of bureaucracy.

lacksconfidenceon Cops are making fewer arrests since N.J. got rid of cash bail

Link to study: https://www.mdrc.org/sites/default/files/PSA_New_Jersey_Repo...

lacksconfidenceon Scalable Python Code with Pandas UDFs

This does use Apache arrow, that's how the data is transferred from spark to pandas and back.

lacksconfidenceon Bleve: Full-text search and indexing for Go

Would you be willing to expand on this a bit? We run multiple elasticsearch clusters and there are pain points everywhere, I wonder where vespa improves?

lacksconfidenceon YouTube Just Demonetized Anti-Vax Channels

They haven't decided that people can't see this content though. The content that is already there is staying up, new anti-vax content can be uploaded and will (likely, i can't know for sure i suppose) be suggested if you are watching another anti-vax video. They have only demonitized the content, deciding they wont pay money for anti-vax content.

lacksconfidenceon How would user-centric payouts affect the music-streaming world?

Suppose in addition to those 100 users you had 2 coffee shops that play the top 40 on repeat 18 hours a day. At least I think that is what was suggested.

lacksconfidenceon Jack Ma: US wasted trillions on warfare instead of investing in infrastructure

Do you live in the us? It's only anecdata but I made about $40/hr in college waiting tables. It's not a bad job.

lacksconfidenceon How we spent two weeks hunting an NFS bug in the Linux kernel

Posix semantics and networks just dont play well together. Notice that binary storage systems these days avoid the filesystem integration (s3, etc.)

lacksconfidenceon World first as wind turbine upgraded with high temperature superconductor

To be clear this quote refers to the traditionally used magnets.

lacksconfidenceon How Harley-Davidson's All-In Bet on Its Past Crippled Its Future

If you want solid acceleration from 60 to 90 you need a top speed in excess of 150. Not sure if that's what GP is referring to though.

lacksconfidenceon Astronauts escape malfunctioning Soyuz rocket

That page says LES can be jettisoned on either side of separation depending on flight profile.

lacksconfidenceon How we rolled out one of the largest Python 3 migrations

go has something in the same general area of error handling called panic/recover. It's not exceptions in the normal sense, and devs expect nothing should panic across api boundaries.

lacksconfidenceon Nike Says Its $250 Running Shoes Will Make You Run Much Faster

some time ago stock car racing was just that, but these days the types of cars manufacturers run in stock car racing are purpose built race machines that have only a passing superficial relationship to what you can find at a dealer.

lacksconfidenceon Pyre: Fast Type Checking for Python

They also transformed php into a very similar language (hacklang) and built a type checker for that.

lacksconfidenceon Ask HN: Are there any purely keyword-based search engines with no NLP?

You can get the raw text with wikitext and whatnot removed from the search dumps made every week (also has various other metadata)

http://dumps.wikimedia.your.org/other/cirrussearch/

These are structured with a JSON string for each doc roughly like https://en.m.wikipedia.org/wiki/Foobar?action=cirrusdump

lacksconfidenceon Deep reinforcement learning doesn't work yet

The author also works for google brain though, so i doubt that they failed to consider GPU/TPU. Really "worker" is just too underspecified to say what it really means.

lacksconfidenceon Word embeddings in 2017: Trends and future directions

Would you be willing to go into a little more detail about what this is actually doing?

What is the shape of the database? Do you normalize each document into a single vector which is compared, or are you keeping per-word vectors? I'm imagining you probably don't have a database with a row for every word, but maybe you do?

How do you pre-filter the list of documents to compute L2 for? If no pre-filtering, can this approach scale into millions of documents?

lacksconfidenceon First detection of the missing half of normal matter in our universe

https://www.reddit.com/r/space/comments/75944s/half_the_univ...

> The approximate distribution in the Universe is 5% regular matter, 25% Dark Matter, and 70% Dark Energy. Half of that 5% was missing, and now found.

> Regular matter makes stars and visible galaxies, so it is "bright". Dark Matter is so named because it does not make things we can see with telescopes directly - it is "dark". We can see the effects it makes with gravity, such as the rotation curves of galaxies, and gravitational lensing. So we know something is there, just not what it is made of. Dark Energy was invented to solve a couple of mysteries. One is the geometrical "flatness" of the Universe, and the other is the apparent acceleration of the Universe's expansion. Like Dark Matter, we don't yet know what it is. But something is causing the flatness and acceleration, so we gave it a name as a place-holder for theories.

> A similar situation happened a century ago, with the precession (shift) of Mercury's orbit with time. We thought it was caused by a planet inside of Mercury's orbit that we hadn't found yet. It was named Vulcan, after the Roman god of fire (not Spock's home planet). It turns out relativity was the right answer - the Suns gravity bends space near it, and causes the orbit to shift. Vulcan was just "a name we gave to whatever causes the observed effect".

> Dark Matter and Dark Energy could turn out to be something entirely different than types of matter and energy, but in the mean time it gives them names we can attach theories about them to.

lacksconfidenceon Visualizations for machine learning datasets

Only if your dataset is really small. It only supports up to a low millions of points

lacksconfidenceon Sorting with GPUs: A Survey

XGBoost recently added GPU support for training. As far as I'm aware one of the reasons the speedup is relatively small (vs say deep learning on CPU vs GPU) is that it spends a significant amount of time sorting which is not particularly fast on the GPU.

lacksconfidenceon VW engineering executive sentenced to 40-month prison term in diesel case

Indeed calling him an engineer, while technically true, suggests something different than what happened. He is an executive, not a line engineer.

lacksconfidenceon The HDFS Juggernaut

I rather like the way elasticsearch handles this. If the server is only bound to 127.0.0.1 then anything goes. If the server is bound to a network interface then various setting must be configured to ensure it works well in a non-testing environment.

lacksconfidenceon A Guide to Synthesizing Adversarial Examples

Is the next step generating adversarial examples and injecting them into the training pipeline?

lacksconfidenceon Most Waymo Patent Claims Dropped in Autonomous Car Fight with Uber

comparing https://www.lyft.com/cities to https://www.uber.com/cities/ it seems like there is a huge discrepancy between the cities that have lyft and those that have uber. Uber has a significant international availability.

lacksconfidenceon Tesla drops 7% after Goldman Sachs says the stock is worth $180

It's perhaps worth noting that musk has said:

> I will announce locations for between two and four Gigafactories later this year – probably four.

This puts them in the range of around 175 (35 * 4 new + Nevada) gigawatt-hours annually. They are certainly looking to compete in this space