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Comment: Re:Check their work or check the summary? (Score 1) 480

by w3woody (#49336491) Attached to: No, It's Not Always Quicker To Do Things In Memory

Really, what's happening is that they're performing repeated concatenations of various length strings--an operation that eventually becomes O(m*n) time, with m being the length of the string and n being the number of strings. (Concatenating strings in Java requires a new string to be created, then the contents of the two source strings copied into the new destination.) Appending a file, on the other hand, is only an O(n) operation, but has a very large constant time associated with it. So, in essence: TL;DR: O(n**2) operations can be slower in memory than O(n) operations on disk for large values of n.

The real lesson is that you should understand what's going on underneath the hood. And in this case, if you're doing a lot of string concatenation operations in Java, you probably should be using the StringBuilder class. I mean, after all, that's why there are multiple ways to do the same thing in Java (like ArrayList verses LinkedList): each offers different performance characteristics, and at the fringes performance characteristics can kill your application.

Comment: Re:Not a watch (Score 1) 111

Rolex, in fact, hand-manufactures its own movements. Some processes of the manufacturing process do use some degree of automation, and of course a number of jigs are used during the assembly process. But they are hand-built movements built internally by Rolex.

The reason why people think Rolex outsources their movements is because Rolex doesn't talk much about their movements, and because Rolex used to use Zenith watch movements in some of their watches, such as the Daytona. (Since 2000, the Daytona has used an in-house movement--and I suspect this move to bring all their movements in-house is what drove Zenith to release their own complete watches.)

Omegas, on the other hand, mostly uses mass-manufactured ETA movements rather than using movements made in-house. While ETA movements are certainly of a much higher quality than mass-manufactured movements from China, they are still basically mass-produced watch movements.

Comment: Re:Not a watch (Score 3, Insightful) 111

Try "thousands", if the movement is built in-house and has more than a couple of complications. Ah, hell; try hundreds of thousands for a custom watch movement with more than a handful of complications--mostly due to engineering costs of designing the movement, which can take years. And when you get to the extreme high end of the watch movement market, they start becoming small analog computers, such as this Patek Philippe pocket watch, which has a complication which calculates the sidereal day, and was constructed in 1933. Or this Jaeger-LeCoultre, which consists of over 1400 individual parts and 26 separate complications.

Comment: Yeah, this will go as well as a lead balloon. (Score 2, Insightful) 111

I own a Rolex DateJust in Gold and Stainless Steel, and someday I'd like to own a Jaeger-LeCoultre Master Ultra Thin Moon 39 in Stainless Steel, as well as a Breitling Navitimer 01. For my father's 70th birthday we bought him a Navitimer 01, which he just loves. (My father and I are both private pilots.)

Here's the thing about luxury watches: for women, you can wear necklaces, wrist bands, rings and earrings. But for men, the only pieces of jewelry that a man can wear (and get away with it) is cufflinks, a tie clip and a luxury watch. And if you're not wearing a shirt with french cuffs, or wearing a tie, then all that is left is the watch.

So basically a luxury watch is jewelry. Functional jewelry, but jewelry all the same. And like all jewelry, if its taken care of you can inherit it from your grandparents (as my wife inherited some pieces), you can receive it when you are young and still wear it when you're old, and you can pass it down to your grandchildren.

When you start looking at luxury watches, you find there are two types: those which use an in-house built movement built by craftsmen who sweat the details and who create all sorts of intricate complications which do interesting things (like keep accurate time, provide a stopwatch function, show the phase of the moon, the day of the month, the month of the year), and those who buy an off-the-shelf movement and wrap it in gaudy jewelry.

From what I've read (I'm not a collector but I'd like to be one someday if I ever really strike it extremely rich, because mechanical wrist watches fascinate me no end), watches from watchmakers who build their own movements are highly respected. Watches from watchmakers who buy their movements from third parties, however, are not very well respected. And the worst are those who use quartz movements: essentially an electric powered watch movement regulated by a small oscillator crystal. Like about 1/3rd of Tag Heuer's product line, many running up into the 10's of thousands, which horticulturally have more in common with a cheap Casio than with an A. Lang & Sohne.

This is why I think luxury smart watches will be an unmitigated disaster. Sure, some people will buy them--because some people have more money than God, and to be able to show off a $10,000 smart watch that you're just going to toss away in a couple of years when the electronics are out of date would be the height of "one upping the Joneses." But I cannot see them being any more interesting to someone fascinated by mechanical watches than a quartz Tag Heuer--it's the sort of watch someone with no sense of connection to the past or any sense of connection to the tradition of hand-crafted watches would shove in your face to exclaim how much better they are than you.

You know: crass assholes.

Comment: Re:It's almost like the Concord verses the 747 aga (Score 1) 157

by w3woody (#49154569) Attached to: Hyperloop Testing Starts Next Year

I just cannot see how a large tube holding a vacuum extending 100 miles or 300 miles or 500 miles or 2,800 miles is ever going to be cheaper than a rail track the same length (assuming right of way problems can be solved--and note the high speed rail system between SF and LA had to be slowed down because right-of-way issues put too many curves in the track) is ever going to be cheaper per passenger mile. And if it turned out per passenger mile a train was cheaper (without government subsidies) than flying a fleet of 737's, do you think investors in their right mind would fly a fleet of expensive 737's when they could run cheaper trains?

And one thing people forget when counting the cost of using trains to transport people or goods is the fact that the first railroads which connected the U.S. continent was built on the cheap with slave labor.

Comment: It's almost like the Concord verses the 747 again. (Score 5, Insightful) 157

by w3woody (#49153497) Attached to: Hyperloop Testing Starts Next Year

Meaning the Boeing 747 became extremely popular while the Concord wound up eventually going to the dustbin of history because per passenger-mile, the Boeing 747 was cheaper than the Concord, despite taking much longer to move passengers from New York to London.

And that's the problem I see with the Hyperloop: sure, it may be technically possible to send passengers in a train in a tube with a vacuum at 800 miles per hour from Los Angeles to New York, but at the end of the day, its the cost per passenger mile that matters. And a large airplane traveling along at 500 miles per hour, which doesn't require 3,000 miles of dedicated hardware to travel through, is going to be far cheaper than buying a 3,000 mile strip of land and building a tube. across it.

Comment: Re:Sounds good (Score 5, Interesting) 599

by w3woody (#49126339) Attached to: Republicans Back Down, FCC To Enforce Net Neutrality Rules

I'm also concerned partially because at its root, the problem with broadband in this country is a lack of local choice. I believe competition (such as Google Fiber) going up against the phone company and the cable company would help lower prices while raising speeds far better than regulation that explicitly acknowledges monopoly status and exchanges (easily watered down) performance demands for guaranteed profit margins on (easily manipulable) books. I mean, the real problem with explicit acknowledgement of monopoly status is an implicit guarantee that the phone company and the cable company may not fail--and if they make poor infrastructure investment choices, they're insulated from failure.

I'm not suggesting this can't work. Only that there are a bunch of ways in which this can go haywire, so to me, the FCC's actions is simply the first step in a very long battle.

Comment: Interviews and candidate quality. (Score 1) 809

by w3woody (#49049607) Attached to: Ask Slashdot: What Portion of Developers Are Bad At What They Do?

I've both helped hire people and have been a hiring manager, as well as the hot-shot programmer and now becoming the wise gray-beard everyone speaks reverently to and then ignores.

When I interview a candidate on the phone, my primary interest is to screen out the candidates who are either obviously lying on their resume, or who have inflated their resume or are otherwise uncommunicative. (You'd be amazed at how many are unable to hold a conversation about the stuff they've supposedly worked on for a couple of years. Almost as if they put it into their resume just to inflate it. And I feel free to go through any part in the resume; for example, I dinged a guy because he put in his resume he was a private pilot. Having a father who was a pilot and learning to be a pilot myself, I asked him questions related to his being a private pilot--which he utterly failed to answer. And if you're willing to lie about something that irrelevant, what else are you lying about?)

In person, however, I may ask a couple of questions about the specific work I'm doing. But for the most part I stick to straight forward development questions: I ask the person to solve a problem which requires a loop, to walk a linked list, to search for primes. What I'm looking for, however, isn't if the person is a mathematician, but how he solves the problem: does he automatically close the curly brace when he writes the open curly brace at the top? Does he store intermediate results somewhere, and how does he chooses to store them? Does he use any naming conventions in his sketched out code? When he gets stumped, how does he talk to me about solving the problem? Does he come up with anything I hadn't thought of?

And that's because I'd rather hire someone who seems smart and communicative and who can sketch code on the fly than someone who may happen to know about public/private key systems.

My theory is that specific problems that revolve around the web site can be learned on the fly: someone who is smart can look up how OpenSSL works, for example, and start implementing code against OpenSSL. But someone who has OpenSSL experience but who is otherwise unable to communicate effectively or solve problems on the fly is going to be useless as soon as we move on to other problems.

And my theory is the same regardless if you're hiring a beginner out of college or an architect with 20 years of experience; the architect I'll just ask much harder questions, as well as probative questions about the sort of design work he's done and the types of design problems he's had to face.

In terms of quality, I've found that roughly a quarter of the people I interview I'd happily work with, but for architectural level stuff, it's hard to find someone who is really good. That's because software development seems to weed people out after 10 to 20 years--and many who survive that long do so out of inertia, not because they're really good at what they do. So if you want someone with 20 years of experience who can architect something complex and get it right the first time--you're going to be looking a long time.

(And if you happen to be hiring in Raleigh, North Carolina and are paying above competitive rates for a first rate architect and developer, send me a private message. :-D )

Comment: Re:Can you say... (Score 2) 266

by w3woody (#48593899) Attached to: Judge Rules Drug Maker Cannot Halt Sales of Alzheimer's Medicine

But think of it: fundamentally insurance is a finite pool that insures against finite losses. Home owners insurance, for example, only pays out at most what the replacement value of your home is, and car insurance only pays out at most what is the replacement value of your car.

This model clearly breaks down--even in government-run "single payer" systems (such as the example I gave about British health care) when you come up against the potentially unbounded cost of a major medical emergency.

After all, what is the replacement value of a human being? $100,000? $1 million? $10 million?

What that strongly suggests to me is that as a society we place more value on preserving human life regardless of cost, regardless of the fact that this cannot properly be handled in a free market environment.

And by definition in the edge cases where the free markets break down is where society should step up and socialize costs.

This isn't a matter of "privatizing the losses"; the breakdown has to do with the potentially unbounded cost of health care for an individual due to circumstances that cannot be properly predicted. For example, I know someone who needs nearly continuous care for the simple reason that she was unfortunately in a car accident that wasn't her fault. Allowing her to die because it's too expensive to let her live is not an option, and assuming that corporations are boundless fonts of endless money is absurd--and penalizing an insurance company because it is unable to cover an unexpected multi-million dollar loss (because as a society we don't want her to die) doesn't really fit the notion of insurance as covering a finite (and maximum) amount.

Thus, door 'C': socialize high-cost patients.

We already do something akin to this with Medicare; the whole point of Medicare was to cover the expenses of the elderly rather than having those expenses covered by private insurance. (And the structure of Medicare is pretty similar to what I'm proposing, with Medicare effectively serving as a back-stop against private supplemental insurance. We just think of Medicare as the base-line insurance and supplemental insurance as covering the 'gaps', when in some sense it's really the other way around.)

Comment: Re:Can you say... (Score 1) 266

by w3woody (#48593509) Attached to: Judge Rules Drug Maker Cannot Halt Sales of Alzheimer's Medicine

Because currently no mechanism exists to force a corporation to take action.

My hypothetical above was premised on the idea that if we were to listen to our emotions and demand that a corporation not leave the health care business simply because it was unprofitable--and after all there are lives to save--that we would create a mechanism which would effectively exempt corporations from folding.

And note if the only way I can exit a business is to zero out millions in assets I own, that's a pretty hefty burden being placed on me.

Comment: Re:Can you say... (Score 1) 266

by w3woody (#48593425) Attached to: Judge Rules Drug Maker Cannot Halt Sales of Alzheimer's Medicine

I would think the solution would be quite the opposite: subsidize the ramp-up costs for generic drug manufacturers so that when drugs fall out of patent they can be easily manufactured by other drug makers.

My understanding is that there are essentially two classes of drug manufacturers--those which make patented compounds, and those which make generics. Patented compounds tend to be very expensive because it can cost billions to bring a new compound to market, largely because of the cost to get FDA approval for the compound--so by default patented compounds will be extremely expensive so that those profits can be used to pay off the R&D costs and subsidize future R&D costs for future compounds. Generics, on the other hand, are cheap because they are not paying for R they're just paying to make the compound.

The real problem, of course, goes around the high R&D costs for creating new compounds. And it is there where, if I were King For A Day, I would concentrate my efforts, by ramping up government funding of research efforts by providing more grant money to universities for basic R&D research into newer compounds, and I would also see if I couldn't reduce the regulatory overhead for obtaining FDA approval.

Time to take stock. Go home with some office supplies.