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Comment Re:Google shits out another fail (Score 1) 91

Another cigar feverishly brainwashes an unruffled bodice ripper. He called her the Interloper (or was it Timosha?). A somnambulist daydreams, but the bride beyond a ballerina eagerly steals pencils from a toothpick. Jacques, although somewhat soothed by a labyrinth near a snow and some seldom lowly gypsy, still can be kind to her from the sprightly gypsy, can be kind to her a trombone related to a maestro with a likeable onlooker, and slyly boogies the dark side of her alchemist.

She prepared to enter The Scary Door.

Comment Re:I don't understand. (Score 3, Informative) 129

Consider minimizing x^2 when x can take values in -10 to 10 (we know the answer is 0, since we only consider real valued numbers). If we wanted to solve this problem, there are several approaches; some example approaches are: randomly try a lot of different values, set the derivative to zero, or try a cutting plane algorithm. In general, we might not know the analytical expression for the function we are trying to minimize (or it might be too complex) so we can't really find the derivative efficiently. Derivatives can also be computationally expensive to compute, so let's ignore that approach.

What we can do is to say let me find a solution for which the function is less than some threshold t, and then keep reducing t till I can't find any more solutions; this is what the article meant by finding a smaller circle inside a larger one (for each value of t, I try to find solutions that are smaller than t).

What cutting planes do is chop up the original function in to pieces - in some pieces, I know the value will be much larger than my threshold (so I don't have to search in those pieces), and in others it might be smaller - I focus on searching these pieces to find a value that is smaller than my threshold (after which I can reduce the threshold and try again). This is what (in a simplistic sense) cutting plane algorithms do; they chop up my search space.

How we select the points for chopping is crucial - bad choices (say choosing one point after another at random, or trying points very close to each other), I spend a lot of time chopping unnecessarily (or not benefiting from chopping by much). We also want to make sure our cuts really do divide the problem in to pieces which I can discard searching, and those pieces I discard should (ideally) be quite large. Until this work, the time taken to decide where to chop was n^3.373; they brought down the time to n^3 (where n is the number of variables that the function I am trying to minimize takes as inputs).

They also said that for special classes of functions, they can really improve the total computation time significantly (from n^6 to n^2).

I'm glossing over (and am certain I've got some details wrong) many issues to give a taste of the big picture idea of cutting plane approaches in general; there has been decades of work on these problems that you can read (I recommend anything written by Prof. Stephen Boyd as an introduction to some of this research).

Comment The two key contributions (Score 3, Interesting) 129

Some very interesting results, but the two key contributions are (almost verbatim from the article):
1) With the best general-purpose cutting-plane method, the time required to select each new point to test was proportional to the number of elements raised to the power 3.373. Sidford, Lee, and Wong get that down to 3.
2) And in many of those cases (submodular minimization, submodular flow, matroid intersection, and semidefinite programming), they report dramatic improvements in efficiency, from running times that scale with the fifth or sixth power of the number of variables down to the second or third power.

So this seems to be a better cutting plane approach that improves the cutting process by reducing the time to find the next test point (in general), and for certain structured problems (like SDPs) this approach reduces the computation time significantly.

This does raise some interesting questions, such as: is there a limit to how fast you can (in a general problem, not using a specific problem's structure) find the next test point? Even if we don't know what algorithm gets us there, it would be useful to have a bound for future research.

Comment Re:Separate H1Bs (Score 1) 112

There is jackass. There are different Visa programs: O-1 and EB-1. How the fuck did the US government spend $500,000 on your education? Unless you are talking about research grants, in which case they would be available to other researchers, not just you. Move along troll.

O-1 is an extremely hard category to get a visa under. EB-1 is not a visa, it is a permanent residence stream (which is what my employer can file for my green card under, IF they choose). Again, EB-1 is extremely hard to get a green card under - it is for exceptional researchers who are presented as such valuable resources that the country would suffer a significant loss if they weren't allowed to remain (hint, most Ph.D. holders are not, despite what their lawyers might argue).

As for who was eligible for the money - yes, the money was available to my advisor to spend on anyone he chose. He chose to spend it on me because he felt my contributions were valuable. The fact that it could have potentially gone to someone else: why is that relevant?

And how did they spent nearly half a million on me? I got a stipend, a tuition waiver, health insurance, travel reimbursement, the occasional computers/software, and full pay in summers for 6 years. So that is nearly $50,000 per year (I was in an expensive state, my initial stipend was over $2k a month) that is shown to the funding agency (NSF). On top of that, there is a university overhead: For every $1 my advisor could spend, the funding agency would have to give $1.5-$1.75, while the university skimmed off the top. That adds up fast, and I rounded up.

Comment Separate H1Bs (Score 5, Interesting) 112

As someone who has benefited from the STEM extension, it is strange that they are targeting this, instead of fixing the H1b issue.

I got my doctoral degree in STEM, and did not get my H1b in the lottery system the first time. If I was forced to leave, the US would have spent nearly half a million dollars on my education, and got one year of tax (not counting my research work, which is freely available to anyone) in return.

Like most people making use of the STEM extension, I am being paid as much or more than my US co-workers. This isn't a "consulting" gig where I am forced to work for my company at sub-standard wages under pain of getting kicked out of the US - STEM graduates have been educated in renowned US universities, and I had four job offers by the time I graduated.

I think there should be a different H1b tracks for people who are hired "internally" i.e. the person is already in the US, and was educated here (people who currently benefit from the 17-month STEM extension), and the other type of H1b that I hear exists (where a company brings in people from overseas purely to do a job).

Comment Re:Translation (Score 3, Interesting) 85

We want employees that work for free!

No, what he wants is to allow paying users the ability to have a lot of the benefits of open source, while not reducing the company's downstream cashflow. It might come as a surprise to you, but not every project can be open sourced and still make money. In fact, I always wondered about the pay-for-support model - why should I make my software easy to use and maintain (eve at large-scales) if my main source of income requires users to come and pay me to help with the product?

Also, this is a scientific computing software - the target market is small as it is. Very likely the core is something that is highly mathematical, and not something the average programmer can work on. I wouldn't be surprised if there were several statisticians and researchers on the payroll. People like these don't necessarily write high quality code - see the R library for example (yes, there are many excellent packages, but a huge number are written sloppily by academics). The customers who use it might need highly specific tweaks for their application - something they can only do with the source. I myself would have loved to "fix" some of Matlab's functions for my specific use case. But if the customers don't have the source, there isn't much they can do.

This type of license should actually become the norm - but it is unlikely to happen. There is always the risk that a customer who bought software might give a copy of the source to their friend, and before long I lost all control of the product. While binaries are still copied today, companies are trying to crack down on it through registration and DRM. If the source is out, there is even less they can do to stop it.

Comment Re: Harvard is the right place (Score 4, Insightful) 348

Also, see "I haven't called the police in 45 years, I don't know why my taxes go to pay them."

While you might not have directly gone to a clinic in 45 years, you definitely have benefited from good healthcare services. Notice how the US doesn't have polio, ebola, or any other epidemic? You're welcome. Now you can also get some meds for the delusions of tyranny.

Comment Assets valuation? (Score 1) 335

I wonder how they value assets? Clearly, sharing a few songs is theft of several million dollars - which makes my MP3 player a treasure trove. Also, patents and other intellectual property cannot be cheap at any price.

I'm curious as to the exact valuation methodology. The links take me to the federal reserve site, which links to balance sheets. While it does list intellectual property, how do you accurately value something that isn't sold/bought on a market? If a company holds a patent that they never try to sell, how can it be valued accurately?

Comment Ask the users. (Score 3, Insightful) 244

The problem with a lot of documentation is that they aren't written from a user's perspective - they are written by people who wrote the software, and know what to do. Letting go of your design assumptions is almost impossible.

I have long felt that the first draft of documentation must not be written by the person who wrote it; you have to allow your users to "send" you the first draft (either through email questions/screenshots/etc.). Then you realize how many assumptions you made that are non-obvious to your users.

Obviously, this isn't really practical for OSS - you might not be able to pay for usability testing and feedback. Which is why I prefer to include screen shots in documentation as much as possible. Also, I try to follow this basic formula for documentation: What (what is the user trying to do - make it clear what this section of the documentation address), How (how can the user achiever her goals), Why (this is where you might, if you choose, try to explain a design/implementation philosophy - it comes third, so that someone who doesn't care doesn't skip the entire section. Clarity and brevity are important.).

This is the principle I follow for user stories as well - create an end-to-end user workflow (which is basically just many small What/How/Why sections tied together).

Comment Develop like you are... (Score 1) 152

... but put in a EULA that you are not.

I think application developers should try to design things as if they are driving the final users decisions - and in their own minds should feel like they are responsible for bad decisions. I have seen way too many apps that are slapped together by a code-monkeys who ignores to understand the importance of clarity (such as units and legends on a graph - "Put in a feature request, and we'll see if we can get it in the next sprint; it is not a critical bug."), or designs like a programmer ("I can just reuse the old UI if I treat X as Y"). Poorly designed documentation ("help is under Options which comes up if you swipe just so") with arbitrary changes to normal behavior and hidden nuggets ("everyone knows that Ctrl+C is copy, so let me disable the context menu and edit menu") are other problems.

No one is suggesting that developers become legally responsible for users decisions. But it would sure help if creators designed their application expecting a child to make a decision using their app.

Comment His interviews will be missed (Score 1) 277

What I liked most about his show were his interviews. Yes, as a satire show he often showed absurdities in the political process, but the segment that made it special for me was his interviews.

While he did bring on celebrities from the media (film starts, bands), he brought on a lot of serious/reputed guests and gave them a chance to speak. I can honestly say I actually learned something from his show. While Colbert had interviews too, it seemed to me Colbert always tried hard to work jokes in to the interview instead of having a more serious conversation.

John Oliver also has a issue of the week in his show - serious issues peppered with light humor, but still informative. If he got guests on his show, it would be a great alternative to Jon Stewart's show.

Comment What does it fix? (Score 1) 167

Long time android user here - currently on a Nexus 5. Lollipop seems to have ruined the android experience. The native calendar app is just horrible (try adding a monthly recurring meeting for the first Thursday of a month on a Tuesday - or try adding a meeting for tomorrow today; the user experience is horrible). It keeps forgetting my settings after any restart (Auto brightness damn you). And their "battery-saver" mode is a joke (here is an idea - let the clock frequency be lower whenever the screen is off, rather than waiting for the battery to drop to 15%, and then making it so slow that it is unusable). Oh, and by all means, make everything white. Launching a native dark theme is impossible for a company with such limited resources.

I'd put CM in, except for some bone-headed work restrictions. I had to jump through hoops to get it remotely usable, and there is no easy way to roll-back to the prior version. The fire phone is looking pretty sweet by comparsion!!!

Comment Re:Automated manufacturing (Score 1) 327

Wow. Did you take the wrong idea from the supply-demand curve.

People won't stock up on TVs just because they are cheap. And there was an unfulfilled demand for Picture-tubes-that-entertain.

How about this - set up a 10 tonne rock shop in the Kalahari desert. Keep it real cheap too. So there is a supply. Let's see how many you sell.

Demand isn't something binary - people don't have a demand for everything for which a supply exists or even an infinite demand for anything for which a demand exists. An opportunity for sales (and jobs) exists if there is a price at which there is an intersection on the supply demand curve.

We do have a demand for space ships. We might even have a supply. The price is off - it costs way too much (both in dollars, and risk to life). So unless the price drops (or a few people are willing to spend a lot on it), there is no meeting of the supply and demand, and no jobs.

The order of hindrance is often price>demand>supply - if no one wants your rock even for cheap, you can't start a profitable business. Often, getting costs low enough is the tough part, but even if you do, there must be a demand for it.

There is a supply of un-terraformed planets, so by your argument, there should be a demand. How come I don't see anyone selling these planets, even at a ridiculous price?

Comment Hey, ask slashdot! (Score 5, Interesting) 159

I have karma to burn. tl;dr - Listen to sales or at the most only make it available to (developers working at) current customers

I'm the lead sales for an Australian ERP software outfit. For the last ten years, we have got an increasing number of competitors breathing down our throats, and the marketplace has become very crowded. Our market has very little vendor lock-in or product differentiation at this point.

One of our lead developers has made our bug tracking list public facing. This is making our life very difficult. Potential clients google our product and see a huge list of bugs. Just a few days ago a huge deal fell through because of this. Our potential customer was horrified that we can't handle dates correctly (it actually has a problem only after 10,400AD), or that the database gets corrupted sometimes (if someone sets of an EMP when data is being written).

When we bring this to our lead dev, he gets moral and claims we shouldn't be in a race-to-the-bottom with our competitors, while ignoring the prisoner's dilemma. Also, while other developers appreciate this transparency, the managers who have the authority to make purchase decisions are scared off by the bug list (and our competitors include our bug list in their sales pitch to scare our current and potential customers - "See? Everyone knows their bugs. It is only hours before you get hacked unless you switch to our product!!"). This is costing us a lot of money that we need to pay people like the lead dev.

We might even be willing to let developers working at our current customers view the bug list, since developers understand and appreciate this. But this lead dev is resistant to that as well. So how can we him to stop making our lives much harder than it already is?

Comment Re:is anyone really surprised here (Score 1) 201

This is very easy to solve with good policy:

And good policy is very hard to get right.

1. After leaving government employment, your private sector salary above your top government salary is taxed a 100% the first year, declining by 10% each year thereafter.

2. Pay after bonuses for regulated industries is tied to the pay of the regulators. Pay and bonuses and equity in excess of the government regulator salary is taxes at a rate of 90%.

As a matter of fact, this will solve just about 99% of all problems in the financial services industry, because it will remove the absurd profit motive that drives bankers to take massively inappropriate risks. We'll end up with a nice, respectable, small, non-dynamic, stable financial services industries, doing things like encouraging savings, and lending out money that is accumulated through savings at a reasonable rate of interest.

So what about pay in kind - does that also get taxed at 90%? How about you set up a corporation and charge as a consultant - does your company get taxed at 90%? We can, of course, start making special exceptions to avoid this - a company formed by a former regulator must pay tax at the same rate as the regulator. But this is how policy creep starts. You want a sensible rule that is easy to enforce and can solve a complex social problem that cannot be avoided by loopholes? It is difficult to get right.

What this country needs is a dime that will buy a good five-cent bagel.