aleyan

This is well known known effect. S&P rebalances it index through out the year and there are always people trying to predict adds and drops and make some money.

The real diseconomy happens in the Russel indexes. They are rebalanced annually with the methodology for adds/drops announced ahead of time. Various funds that are pegged to Russel are forced to rebalance at this time buying and selling huge baskets in one day. To avoid large stock market movements and capitalize on them traders try to predict the changes to the index and prebuy the rebalance trade. Their actions through the market leading up to the rebalance and agreements to sell the rebalance trade to the Russel pegged funds reduce price swings on the day of the rebalance.

Trading desks that engage in the Russel trade spend the entire year preparing for it, modeling the methodology, acquiring clients for the rebalance trade, and prebuying the trade. Their profit comes from the difference between the closing price (mostly governed by Russel adds/drops) on the day of the trade and the price that they prebought at. Essentially their ability to accurately predict the rebalance add/drops and acquire clients to sell the rebalance trade to. There are desks that make $10s of millions this way on that day. There may be desks that make $100 of millions this way.

PS. I may not have stated it clearly, but funds that are pegged to Russel indexes make agreements with external traders to handle their rebalance trade for them at a fixed bps to the closing price. Traders are able to make money on this because they can take on risk and prebuy the trade; something that the Russel indexed funds can not do.

TL;DR of the parable. Incumbent businesses will lobby and use professionalism as an excuse against individuals using their own resources to do ad-hoc business. Article makes an argument that this is bad.

I found this article as print out on the floor of a bathroom on an equities trading floor of Goldman Sachs circa 2010. It intrigued me and since then I have shared it with my friends and family, who seemed to have enjoyed it. I post it now because it reminds me of the arguments surrounding new car hailing services and on demand short term housing rentals. Our problems aren't entirely new, so why not leverage some wisdom of decades past when reasoning about them?

    When I think I'm finished with an article, 
    I set the print speed to Slow. This runs the 
    printer at about 100 words per minute, or roughly 
    the pace of reading aloud. I stuff my ears with 
    earplugs and then lean over the platen as the 
    printing begins. Watching the article printed 
    at this speed is like hearing it read; infelicities 
    are more difficult to ignore than when you are 
    scooting your eye over words on a page.

The author forces himself to read slowly to make his mind reevaluate his words. Does any one else do this or perhaps pass their compositions through a text 2 speech software? It seems like it could potentially be a useful writing aid.

1) Perceived Risk. AI makes any activity 10 times scarier than same activity without. People will irrationally fear that their AI PA turns into HAL 9000[1] or their self-driving car turns into Project Satan[2].

2) Actual Risk. Software has bugs. When software is meant to give out some subset of data it is not unknown for it to give out more data than it means to. A human PA may make mistakes and blurb something that he/she shouldn't have, but he/she also knows when to stop giving out information. If a particularly trained AI starts leaking out information, it will happily do so for user after user after user.

[1] http://en.wikipedia.org/wiki/HAL_9000 [2] http://futurama.wikia.com/wiki/Project_Satan

To get pleasantries out of the way, I am glad to see Matt Turck here on HN. The meetup he hosts, Data Driven NYC, attracts a large number of both very high caliber of guest speakers and attendees. The several times I have been there, I enjoyed the presentations and the discussions afterwards thoroughly. X.ai which I was introduced to at this meetup, was one of the more interesting startups there. If I wasn't as happy as I am at Handy, x.ai would be foremost among companies I would consider working at; their challenges are many. This is one of the highest endorsements can be bestowed upon a firm and its product by an engineer.

While x.ai is very exciting, I have several concerns about their product and their chances at success.

1) Most meetings are scheduled internally within a firm where calendars are visible and shared. An AI PA that simply locks down time slots doesn't have much value add beyond what the calendars currently provide.

2) There are privacy concerns. Many will not trust x.ai with their calendar data due to concerns about x.ai data-mining or sharing their data.

3) There are other privacy concerns. People may not trust Amy and Andrew not to be social engineered by others to leak their calendars. The fact that person is busy at a certain time or for a certain duration or within a certain vicinity is potentially useful to people whose goals are more than just scheduling a meeting. This kind of over sharing may not be worse than goes on with Facebook, but the letters A.I. will make it sound scarier.

My last point is a wish. Most of my non-work meetings are scheduled over #1 text messaging and #2 Facebook. I would like to see x.ai support other mediums than just email.

For those of us using macports, the port file was updated an hour ago: https://trac.macports.org/browser/trunk/dports/devel/git/Por...

    sudo port selfupdate
    sudo port upgrade git

    git --version

Ran the Mac OS version on Yosemite with 0.4.2 version of the Oculus SDK on a DK2.

Loved it. Awesome job. Feels like a haunted house that moves around you instead of you moving through it. Very immersive. Will show this off to other people.

IPD was kind of weird though. I felt like a giant in the dungeon. What kind of camera setup did you use to film this, and how far apart were the cameras?

Also, I did not feel the 3D sound, though the issue may have been with my ears or me not paying attention to it. I will retry again later tonight and report on the results.

> It's part of a broad government push to repatriate American funds into American banks.

Not exactly. US government wants to repatriate taxes earned by American people and capital abroad and making foreign banks accountable to US is part of making that enforceable.

On-shoring of dollars into US accounts because they can't be kept easily abroad is unpleasant side effect. When US dollars leave US, economically it is the equivalent of the World giving US treasury an interest free loan. The return of those dollars is essentially a repayment of that loan and acts as inflation economically. This could be useful, but the US government already has a direct lever on the quantity of dollars in the US economy through the FED.

To summarize, US Gov only wants the return of dollars that it will receive as taxes, but by all means don't bring back the rest.

Has anyone actually answered this question on the spot without help and without knowing it? Probably not without help, but then how do we judge the amount help given to an interviewer?

I have been going through my own crises of interview question. My go to question for interviews which I have asked of about half a dozen candidates so far, wasn't completely flubbed only once. The only people I know who gave the good answers besides myself were my boss and our intern from MIT during mock interviews. I have been grading the candidates not on being able to write the solution in code like I intended, but on being able to come up independently with bits needed for the solutions. This has been quite unsatisfactory. How do I know if my question is too hard, or if something else is wrong, like prescreening of candidates?

"They were called khrushchevkas — five-story buildings made of prefabricated concrete panels. "They were horribly built; you could hear your neighbor," says Edward Shenderovich, an entrepreneur and Russian poet. The apartments had small toilets, very low ceilings and very small kitchens." <- from the article.

I grew up in a 5 story prefabricated concrete Krushevka in Moscow. This is my experience:

  [ ] you could hear your neighbor
  [ ] very small toilets
  [ ] very small kitchens
  [X] small toilets
  [X] low ceilings
  [X] small kitchens

Kitchens and bathrooms were small, but not much smaller from what I encounter in some NYC apartments. I feel use of the word "very" was inaccurate in the article.

Krushevkas may have been derided as ugly pox upon the cities, but at rubles to bubliks they got people out of communal apartments. Many families were able to live in their own spaces for the first time.

That makes sense.

There is also a question of will though. IANARS (I am not a rocket scientist), but it seems to me a lot of political investment behind rockets in USA and USSR was military in origin. This meant the rockets and rocket engines they spent most effort on was for single delivery of a warhead with no chance of reuse. Civilian rocketry was just a byproduct of efforts to deliver the bomb. We see this with Russian commercial satellite launches using repurposed ICBMs. If military didn't care about the reuse, the civilian programs would have had to work on it on their own.

I believe that with enough will and advances in technology, engineering problems for reusable rocket engines could be overcome.

Well done. I have been working with animating 2d images with a hand constructed depth map in the past to a decent 3d effect[1]. The illusion when guided by your mouse as in the OP seems to be much stronger then in left-right strafing that I did.

One point that can be worked on, as pointed out by other people here is the occluded pixels (this is an issue when an image has sharp changes in distance from the camera). You simply can't show what wasn't seen by the camera, so you have to fake it. In the pre-baked animations I did, the occluded pixels were duplicated and then manually fixed by me in Photoshop.

Perhaps the solution here would be to capture and store images from several perspectives. These could then be used to generate the depthmap using what algorithms Lens Blur used, and also to interpolate the occluded pixels when viewing the photo from different perspectives.

[1] http://fooladder.tumblr.com/

Congratulations to the quantopian team.

Trading on real data is very different from simulated trading on historic data. There are a lot of leaky abstractions and assumptions that happen during simulations that cause problems once you put real money to work. In the past, here on HN, I have criticized quantopian several times because no one has actually used quantopian to trade real money. This is no longer true.

It will take a lot of time and a lot more capital to figure out all the holes, but they are finally on the right track and I am glad they have 20 people already trading. That is 20 sets of eyes balls to look for lack of fidelity in the simulations.

Personally I am interested to see how good their transaction cost model is when trading hundreds to thousands of shares at a clip.

Trust is something hard to come by and when dealing with foreign sources you have to rely on translators and their issues. What is worse, even if the translators are reliable, alterations can be made after the fact, but verification is difficult because of language barriers.

Here is an example that my father found about Putin's person of the year interview with Time. Time published a full transcript [1] in English and Kremlin published the full transcript [2] in Russian. The very first question is different! Kremlin's version includes a question where the reported bungled the Putin's birthday and though he was born in 1946 instead of 1952, but Time omits it. It wasn't a very substantive question, but it did set the tone for the interview and the difference is upsetting. As far as I know this particular issue has not been widely discussed for the past 7 years.

If media and/or governments alter the smallest records for reasons of incompetence, what do they do to hide larger errors?

[1] http://content.time.com/time/specials/2007/personoftheyear/a... [2] http://translate.google.com/translate?hl=en&sl=ru&tl=en&u=ht...

I like the labor reducing (and cheapening) idea of printing on the canvas first and then painting on top. This removes the sketching time and eliminates the whole class of problems relating to proportion and perspective.

The idea of shipping canvas in tubes has me less enthused. Most people can't stretch canvas over a frame on their own, so they have to get somebody to do it for them. That person probably isn't very cheap in their locale. This step is potentially done better at the factory.

Next the stretched canvas needs to be framed. Once I have my 12" by 12" canvas stretched and then framed, I wouldn't be surprised that it cost me some multiple of the $53 price. Besides a costing a bundle more than quoted, I had to do some legwork in meatspace to get it wall ready.

The quality of the work has to be good too, otherwise the prestige of a painting will be overshadowed by its gaudiness. Might as well hang the original photograph then.

Overall, not an easy business to get right, but monetization is built in. I hope you succeed.

I first encountered this line of reasoning in Bulgakov's excellent 1925 book, Heart of a Dog when a doctor advises one of his friends:

  If you care about your digestion, my advice is—don't talk
  about bolshevism or medicine at table. And, god forbid—never
  read soviet newspapers before dinner.

It seems to me that it has long been known that unactionable information is not good for you.

Curiously, another HN reader expressed the same [1] feelings about HN.

[1] http://anton.kovalyov.net/p/soviet-newspapers/

Looks fantastic.

I noticed that all the lenticulars demonstrated have horizontally aligned lenses for a final image that you rock head to heel. Why not offer a vertically aligned lenses for a final image to that you rock side to side? If I understand correctly, a user should be able to do this themselves if they flip the source image 90 degrees, but an option would be nice. There are some issues with your eyes seeing different frames with vertical lenses, but that could be used for cool stereo effects too.

This game is to Balderdash as Cards Against Humanity is to Apples to Apples.

There seems to be a trend of taking classic games and putting up dirty clones of them on indiegogo. Not a bad thing, just an observation. I suppose they are filling a niche that the original game manufacturer can't pursue because it would damage their image to put out a game with naughty ideas.

PS. I would like to hear what actually went into making a physical manufactured party game in only 12 weeks.

EDIT: ultramundane828 expressed the same sentiment as me slightly before me. Having played cards Cards Against Humanity, it does innovate a little grammatically over Apples to Apples by replacing adjective cards with Mad Lib cards.

On a second look, it may not be as hard as it first appeared. When shading, the artist will just have to be very conscious of the angle of incidence from the light source. We will see how difficult this is once alpha is released and we get a chance to compute some normal maps and debug their lighting profiles.

Preface: I have no experience in 3D graphics.

This is a very cool technique. I have been thinking about how to generate normal maps for traditionally drawn 2D images ever since seeing the normal mapped canvas demo[1]. This seems to be an answer.

Drawing lighting profiles that are coherent however does not seem simple. One of the uses of this technique "Depth maps for stereoscopic 3D" appears much more complicated to me that drawing a depth map by hand in the first place. I drew a depth map for my drawing Starry Venice[2] as a step in making it into a wigglegif. Drawing multiple correct light profiles to generate the depth map for a scene such as Starry Venice seems almost impossible to me. This is far from the base use-case, but still.

It will be interesting to see how forgiving the creation of the normal map will be on imperfect light profile inputs. Also, it will be interesting to see if any artists who are masters of this technique will emerge.

[1] http://29a.ch/2010/3/24/normal-mapping-with-javascript-and-c... [2] http://fooladder.tumblr.com/post/61216111704/starry-venice

They look right. Exactly the right color. Spoons look a bit different from what I remember, but I think this is it. Thanks!

Good job figuring it with my Dan Quayle moment (corn vs potatoe).

I have completely forgotten about the discount outside of rush hour at Goldman. It just didn't figure much in my lunch time planning, and I loved lunch.

The one remarkable thing about their cafeteria that stuck with me was the cutlery. All disposable utensils outside of chopsticks were made out of biodegradable corn and they were the best disposable utensils I have ever used. The utensils were full sized and the right stiffness. There were no sharp edges and the texture was slightly rough, much nicer than plastic.

Since leaving GS, the only thoughts I had about their cafeteria was why haven't I encountered as nice disposable utensils as I had there.

Not quite right. Finger prints are considered "something you are". Always with you, can be impersonated, but can't be changed. Something you have have would be a key or a token, that can be changed if compromised.

Agree with the rest of your comment. Cocktail "something you are" with "something you know" and "something you have" for potent results.

I have been living in NYC for the past 5 years. These are the things I dealt with:

  [ ] muggings
  [ ] gang-related activities
  [ ] car theft
  [X] false restaurant reviews

Fraunces Tavern[1], the oldest surviving building in Manhattan, built in 1671 should have been glowing red in the Financial District. In this visualization it is shaded blue for 1900. It was the first building I checked and it was spectacularly wrong; this does not bode well.

[1] http://en.wikipedia.org/wiki/Fraunces_Tavern

Obligatory XKCD: http://xkcd.com/977/

I wonder if there is some sort of theorem that describes which fidelities you can get out of a flat projection of the surface of a sphere. For example, a projection could have accurate area ratios or accurately reflect point to point distances but not both.

This such a disappointing article it borders on journalistic dishonesty. They make out Belarus to be some Terra Incognita being discovered by some brave Nokia volunteer(?) explorers. It is simply not the case, Nokia's competitors in mapping space, Google and OpenStreetMap already have excellent maps. Just compare maps of Zhodzina, a provincial Belarusian town I chose at random between Bing (Nokia)[1] , Google [2], and OpenStreetMap [3]. Nokia's map is hole, whereas Google and OSM have streets and names associates with them. This pattern follows from Minsk to the provinces.

The details offered by the article may be of some interest, but their veracity simply can not be trusted due to glaring omissions, half truths, and down right falsehoods in the article on the broad level. Shame, shame, shame on NY Times.

[1] http://binged.it/14p2lTY [2] https://www.google.com/maps?q=Zhodzina,+Minsk+Province,+Bela... [3] http://www.openstreetmap.org/#map=15/54.1038/28.3231

Agree on rule #1.

> " or a way to contact their support line and confirm your identity"

That is one of the nice things about SMS 2-factor auth, the backup authentication method (lost phone) is on the wireless company instead of you. I suppose twitter can handle the extra responsibility though. They have ways of verifying accounts, so now it is just a question of scaling that for support.

What happens if I lose my phone? I have human ways of authenticating myself to my wireless provider and getting a new phone with same phone number back. Do I need to backup the RSA private key?

If my phone is compromised physically or with malware, this does nothing to protect my twitter account. Both proverbial eggs are in the same phone.

Smell is a safety feature. It helps you avoid rotting food, rotting bodies, things contaminated with feces, unexpected chemicals, smoke and fire conditions.