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Comment: Video and audio are time-rate fixed (Score 1) 81

by Solandri (#49379085) Attached to: No Film At 11: the Case For the Less-Video-Is-More MOOC
When you try to absorb information via video or audio, you're pretty much limited to the speed at which the video or audio was recorded. If you find the pace too slow, players like VLC can speed it up a bit, but I find that beyond about 1.5x the audio compression and frequency shift correction ends up distorting it enough that the speech processing centers of my brain can no longer clearly identify the words being spoken. If the pace is too fast, your only choice is pause and rewind.

When you absorb information visually, either by reading or looking at pictures, you can go as quickly or slowly as you like. It's like the audio machines I used when translating - glorified tape recorders with frequency correction based on tape playback speed, with foot pedals so you could go faster, slower, or rewind. Except you don't need any of that equipment with text or pictures.

This is why video and audio will always be an inferior method of transferring knowledge than reading and diagrams/pictures. You can use video and audio samples to demonstrate things which are best seen/heard in real-time, and live presentations are superior if they allow interaction between instructor and student. But for a general information dump, text and pictures allow the highest bandwidth, with the bandwidth controlled by the reader's mind. Video is like presenting a textbook as a flash animation with a fixed scroll speed, where you need to mess with clumsy fast-forward and rewind buttons to control bandwidth.

Comment: Re:Choice? (Score 1) 221

by Solandri (#49354363) Attached to: Broadband ISP Betrayal Forces Homeowner To Sell New House
There are a lot of ways to get broadband internet which are a lot cheaper than selling a house. He mentions the nearest Comcast plant is 2500 ft away, and that he goes to a local Starbucks for their free wifi when he hits his cellular cap. So it sounds like there's a clustering of businesses about a half mile away, with broadband Internet. All he needs to do is make friends with a one of the businesses there, offer to pay half their monthly Internet bill if they'll mount an antenna on the roof, and mount a receiving antenna at his house. Best case it's about $150 for a pair of antennas and wireless bridges. Worst case it's $500-$1000 more to build a tower on his property to mount his antenna higher for clear line of sight.

He chose to sell his house instead of trying that.

Comment: Re:Easy Solution (Score 5, Insightful) 221

by Solandri (#49354205) Attached to: Broadband ISP Betrayal Forces Homeowner To Sell New House

Pass a law that if a service provider says that they offer service to an address they must do so by law. No fines, they have to install service. If that means $30,000 in new cable to be laid, then so be it. The service providers will get their service maps in order really quickly and we'd have accurate coverage numbers for the country. .The service providers will get their service maps in order really quickly and we'd have accurate coverage numbers for the country.

This is the problem with people who typically see regulation as the solution to everything - they assume the best possible outcome for themselves. When in fact the best possible outcome for the company targeted by the regulations is what will really happen.

If your proposal were implemented, the best possible outcome for the company is that they simply discontinue providing coverage maps for the country, and require you to call in. You will verbally be given a quote with a disclaimer that quoting a price does not constitute a guarantee that your address is within their service area. And if you need that guarantee, you will need to subscribe for a year and put down a deposit so they can send someone out there to survey the location. If it turns out they can't provide service, they'll refund your deposit. But if they can service you, you're committed to the year's subscription (thus neatly preventing you from finding if another ISP also covers you).

How do I know? Because I just went through this trying to get Time-Warner cable internet at the commercial building I manage.

Comment: Re:Absolutely crucial (Score 1) 137

Fixing it by harmonizing VAT rates would require treaty changes and be politically hard to hand one of the big financial levers to the european central bank, especially given not all countries are in the eurozone - imagine the US forcing all state sales taxes to the same rate, set by the fed, and you get the idea.

The U.S. is even worse off. There are nearly 10,000 sales tax jurisdictions in the U.S.

The solution is to reverse who is responsible for updating the tax rates. There are a lot more retailers than there are tax jurisdictions. It's stupid to force every retailer do duplicate each others' efforts and update tax rate data from every tax jurisdiction every day. Instead, make it the responsibility of each tax jurisdiction to update their tax rate on a central database every day. Every retailer can then simply download an updated tax table from the central database at the beginning of every business day. That completely eliminates the duplicated effort and produces the most efficient economic system (for distributing sales tax rates at least).

Comment: Re:Ugly Solution (Score 1) 197

by Solandri (#49345997) Attached to: Japan To Build 250-Mile-Long, Four Storey-High Wall To Stop Tsunamis

A huge wall seems like an ugly and in-elegant solution. Building large mounds of forested areas would be much more attractive and useful (as a wildlife, tourist, and a tree resource). As a backup - build man made lakes at a higher altitude that can dump into the ocean in under 20 minutes and time the water dump to coincide with the tsunami.

If you watched video of the 2011 tsunami, you've seen that it isn't a singular wave which comes ashore and retreats back (there are such tsunamis, usually caused by local landslides, but this wasn't one of them). It's more like a 20 minute tide, inexorably raising the mean sea level so seawater went further and further onto land (relatively slowly too - a car could outrun it). So mounds and forested area would do nothing - the seawater would just go around them. Lakes of water dumped in would do nothing either, unless the volume of water in the lakes approached the volume of water coming in from the tsunami. Meaning you'd need a 250 mile lake, which creates the risk of an artificial tsunami should the restraining systems for the lake water ever fail.

The concrete barricade idea doesn't have to be ugly. Inevitably, every beach has a road parallel to it. In California it's highway 1 (Pacific Coast Highway, or PCH). They could simply elevate that road atop 4 stories of concrete. The beach could be accessed through tunnels in the concrete, with a mechanical door manually shut during a tsunami alert, and metal backup doors set up like one-way valves that automatically slam shut in the event of water pressure on the other side. From the beach side, you'd have a view of the ocean, beach, a contiguous concrete wall, and the mountains in the background. Maybe the tops of a few tall buildings, but it should be a simpler and uncluttered view that may actually be an improvement over the current cluttered cityscape. From the city side, you could only see the beach and ocean from taller buildings. But smaller buildings which lose their ocean view would be the ones most at risk from a tsunami anyway, so you're making a pure risk-based trade-off there.

Comment: Re:Security is hard... (Score 1) 736

by Solandri (#49345713) Attached to: Germanwings Plane Crash Was No Accident

If media is correct one of the pilots wanted to crash the plane, and used the cockpit security system to prevent the other crew from interfering. This was not part of the threat model, and that made the current security system work in favor of the attacker instead of the rest of the crew. Not good. It cost 150 lives.

I disagree that this was not part of the threat model. It obviously was part of the threat model since they thought to include an access code to allow someone outside to get in (and to counter that, they added an override for that inside).

You have to understand that almost nothing in life has a sharply defined line between the correct answer and wrong answer. Usually it's a very fuzzy line. That means there's no perfect answer which is exclusively correct. Something which reduces the risk from one threat increases the risk from other threats. You have to estimate the prevalence of the risks you're likely to encounter, and tweak your design based on those estimates. While you are not eliminating risk, you are minimizing it.

That's why a single example of a failure of a system is not necessarily evidence that the system was poorly designed. When UAL 232 crashed, one of the flight attendants was haunted because she had told a mother to put her lap child (a baby flying for free because the mother could hold it in her lap) under the seat in front of her for the crash landing as per regulations. The mother survived, the unrestrained child died. She led a multi-year campaign to convince the FAA to require all babies and small children have a purchased seat, so they could be strapped in in the event of an emergency landing. The FAA (correctly) recently declined her proposal. See, her thinking was limited to the singular incident of a plane crash. The FAA's thinking extended beyond that. Planes are a lot safer than cars. If you require babies and children to have a purchased seat, you increase the cost of flying. More people then opt to drive instead of fly. And consequently more babies and small children die in car crashes than would've died in plane crashes. So on average, an unrestrained child flying is a lot safer than a child in a car seat on a road trip.

It's exactly like vaccination - yes some people get sick and a few even die from the vaccine. But the overall benefit is so great that it outweighs the small negative consequences of the vaccines being worse for a few random individuals. This is also why anecdotal evidence is so dangerous, and unfortunately a popular line of reasoning among armchair quarterbacks with an axe to grind. They deliberately obfuscate the trade-offs to make their position sound more reasonable. (It's also a major difference I see between the thinking of engineers and scientists. Engineers are forced to deal with the real-world slop of nebulous risk conditions every day, and they get this concept of risk trade-off immediately. Scientists are used to dealing with experiments which minimize if not eliminate this uncertainty. They tend to be critical of solutions which trade-off risk, always believing there must be a way to do it which doesn't have a trade-off. And take a bit more convincing before they'll admit the trade-off is beneficial.)

Comment: Re:You are the problem (Score 1) 224

by Solandri (#49332451) Attached to: $1B TSA Behavioral Screening Program Slammed As "Junk Science"
Completely agreed that TSA is just security theater. However:

For example, you're allowed to leave tablets in your bag (apparently, the dangerous part of a laptop is its keyboard? That's all that distinguishes it from a tablet these days) and the ones with metal cases do a pretty great job of blocking X-ray.

The reason you have to remove your laptop is because the circuitry on the motherboard clutters up the x-ray image, making it harder for the people monitoring it to quickly tell what else is in your bag. A tablet is mostly battery with a small circuit board along the edge. Laptop motherboards have been shrinking, but they still take up about half the interior of the laptop thus cluttering up a lot more of your carry-on than a tablet.

And the metal case does very little to the x-rays. You ever read those signs saying not to stick your arms inside the x-ray machine? They're there for a good reason. The x-rays they use are much more powerful than what're used in a medical x-ray, and can produce a clear image through a fair amount of metal.

Comment: Re:On the Nexus anyway this is disabled by default (Score 1) 127

Smart lock is actually too lenient. It'll auto-unlock if it's in a trusted location or connected to a trusted device (e.g. bluetooth headset). The apps which provided similar functionality in Jelly Bean did it right. The first time you used the phone when connected to a trusted device or in a trusted location, you had to unlock it. After that, the app kept the phone unlocked until it left the trusted place or disconnected from the trusted device.

Lollipop's smart lock will auto-unlock the moment the trusted conditions are met. That is, if you have your workplace set as a trusted place, a co-worker who stole your phone simply has to be at work to unlock your phone. There's no need to enter the unlock passcode the first time it transitions from a locked to an unlocked state. Simply satisfying the trusted conditions will clear the lock.

Comment: Re:It has an acronym , so it will fail. (Score 3, Insightful) 149

by Solandri (#49321267) Attached to: Obama To Announce $240M In New Pledges For STEM Education

Endless educational financing is already available.

In what universe would that be?

This one. The U.S. tops the world in education spending per student (p. 4, chart B1.1).

The idea that we're not spending enough on education is a myth, manufactured by those who are sucking up the largest chunk of education dollars. If you ever take the time to dig through a school district's budget, you'll find that the biggest single item is administrative overhead. Basically school payroll is top-heavy with too many administrators and managers.

Every time a budget cut is threatened, they make sure the cuts land squarely on classrooms and teachers, creating an artificial financial crisis. That riles up the teachers' unions and PTAs who broadcast the message that we're not spending enough on education. We really are spending more than enough, but from their perspective we aren't because the administrators aren't passing the money through to them. When the tactic works and public pressure forces legislators to increase school budgets, the administrators divert the bulk of it to fattening up their pay (or hiring more administrators), throwing a few token bones to teachers and classrooms (e.g. an iPad for every child in Los Angeles, which was probably a kickback scheme for the administrators who selected which companies got the contract).

Comment: Re:Fuck those guys (Score 1) 569

The problem is that police would respond with that level of force based upon an anonymous tip.

The problem is more the police than the swatters.

The problem is the media. I've seen hundreds of news stories where with 20/20 hindsight they'll say police received an anonymous tip regarding a [murder/bomb/bad thing] but failed to act on it. I have never seem them once mention the hundreds of incorrect or fake anonymous tips the police receive. The only time I've seen that mentioned is when the police (FBI, etc) mention it themselves during a live press conference.

Assuming a relatively constant percentage of the population who'll call in fake tips, the more effective your police force, the lower the ratio of real tips to fake ones. For the simple reason that when less crime occurs, the fewer real reports of crime you'll receive. Basically your signal is dropping so low that the noise begins to swamp it out. So ironically, the more effective your police force is, the more likely they are incorrectly dismiss a real anonymous tip as fake.. The media does society a great disservice by portraying an anonymous tip as a strong signal with no noise which the police should have acted on, when it was in fact a weak signal often indistinguishable from the noise.

This puts the police in a position where they feel they'll be raked over the coals if they ignore any anonymous call about something serious like a murder. And they will go all-out to respond to it, "just in case" it happens to be true, in order to avoid the media circus that'll result if it was true and they didn't respond.

The problem is a police force filled with the same adrenaline junky types that call in the swatting.

Yes that is a problem. But cooler heads would prevail and would overrule the adrenaline junkies if the media treated missed opportunities from anonymous tips more fairly, instead of exploiting them as an opportunity to take a cheap shot at the effectiveness of the police. Think of what goes through the police supervisor's head while deciding whether or not to approve the SWAT raid:

  • They conduct the raid and it turns out to be fake. A little bad publicity, family inconvenienced for a day or two, everything goes back to normal.
  • They conduct the raid and it turns out to be true. Media portrays them as heroes.
  • They don't conduct the raid and it turns out to be false. Nobody ever hears about it.
  • They don't conduct the raid and it turns out to be true. Media crucifies them. Supervisor loses his job.

There's little to lose and a lot to gain by doing the raid. While there's nothing to gain and a lot to lose by not doing the raid.

Comment: Re:Or maybe... (Score 1) 417

by Solandri (#49317999) Attached to: How 'Virtual Water' Can Help Ease California's Drought

don't plant water-intensive crops in a drought zone? Naaa, that would require actual understanding of the situation.

That's a horribly naive way to view the situation. It's a lot more complicated than water-intensive crops in a drought zone. Soil, amount of sunshine, average daily temperature, and seasonal variation in temperature all play a part, and are very favorable in California. When water was cheap, the additional cost of piping it or drilling for it was outweighed by the all the above factors. i.e It was cheaper to pay for the water and grow the crops in California, rather than try to grow them elsewhere where water was more plentiful but the other conditions not as conducive to growing certain crops.

Now that water has become more scarce, its market price should be increasing to reflect its increased scarcity. But that hasn't been allowed to happen with politics being what it is and agriculture being a large portion of California's economy. Consequently water is under-priced. And when you under-price a resource, demand outstrips supply, and you get a shortage. Which is exactly what's happening.

Comment: Re:Global Entry Kiosks already have this (Score 1) 97

The iris scanners aren't new either. I was in Nexus (U.S./Canada pre-screening) before Global Entry existed, and the airport kiosks used iris scanners back then. They ended up replacing them with the fingerprint scanners currently used for Global Entry (these programs use the same kiosks at the airport). The word going around among Nexus members was that the iris scanners were too unreliable, which I can believe. I had to take off my glasses, and hold my eyelids way open with both hands, and maybe the machine would correctly ID me. The fingerprint machines have correctly authenticated me on the first try every time, even after I made about a 15mm cut across my fingertip while repairing electronics and the two halves healed slightly askew.

Interesting that they're planning to bring back the iris scanners. Either they've improved the technology, or someone in DHS really likes iris scanners regardless of how well they (don't) work. Possibly bribed like with the airport backscatter x-ray scanners.

Comment: Re:It's win-win. (Score 1) 111

I still can't understand why the fuck people are racing to create smart watches. how many times does this segment have to fail before they realize this is a case of them searching for a problem that doesn't exist.

Because history says you're probably wrong. The first mechanical clocks filled up a room. Refinement of the design allowed them to become small enough to sit in the hallway of your house. Replacing the pendulum with a spring allowed them to shrink enough that you could pack in your bag and take it with you while traveling. Miniaturization shrank that until they were small enough to carry in your pocket. Further miniaturization and the introduction of electronics allowed them to became small enough to be strapped to your wrist.

Computers were first large devices that took up most of the room. Then the shrank to something small enough to fit on your desk at home. Then something you could pack in your bag and take with you while traveling. Further advances and reduction in power consumption (reducing battery requirement) allowed them to become small enough to carry in your pocket. The next step down in size is something you can strap to your wrist.

The main impediment to further miniaturization right now is screen size - both for display and data entry purposes. My hunch is that as soon as someone begins mass-producing flexible displays, that barrier is going to vanish. Your computer/phone will be strapped to your wrist with rudimentary interactive functions handled via its small built-in display. If you need a larger display, it'll come in the form of a pen you carry in your pocket or purse which unfurls like a scroll and connects wirelessly to your watch-computer. Unroll it part-way for a display the size of a current smartphone display. Pull it out further for a display the size of a tablet or small laptop. Speaking of which, your "laptop" will simply be a wireless keyboard you can add to your travel bag and use in conjunction with your watch-computer and unrolling display.

Comment: Re:The answer is obvious (Score 1) 65

by Solandri (#49289617) Attached to: Feds Fine Verizon $3.4 Million Over 911 Service Outage Issues
You do realize that Verizon, Comcast, et al have local monopolies which are government-granted? If the telecom industry was deregulated and this had happened, the Feds would've been happy to crucify Verizon to set an example for competitors. But because regulations have made them the only game in town for so many people, the Feds have no choice but to impose a fine which smarts, but won't really affect Verizon's operations. Verizon is "too big to fail" by government mandate.

Computers will not be perfected until they can compute how much more than the estimate the job will cost.