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OKCupid Experiments on Users Too

jimmyswimmy Huge differences (161 comments)

There's a huge difference between A/B testing, designed to optimize your website with the direct intent to improve sales, and performing experiments on how different news feeds affect your users' moods. A/B testing typically comprises changes in button size and color, website layout, font variations, etc; should we lead with the price, or with the benefits, or with something else? On the other hand, what FB and OKC are doing - admitting to, and proudly! - amounts to wholesale experimentation on their users, with undisclosed intent - perhaps to make the users come back more frequently for another hit.

This seems akin to me to cigarette companies manipulating the nicotine content of their products. That didn't go over well when it was finally disclosed.

You can't just tell people you "might" experiment with them, they have to know and understand that they are part of an experiment. They don't have to understand the goal, they just need to know what they are part of, and they have to consent to that experimentation. One could argue that A/B testing should submit to the same level of scrutiny as other psychological experiments, but I think people generally understand and accept corporations' profit incentive. We don't accept the idea that a company might wish to screw around with our mood or set us up on a date when they know it won't work out.

about 2 months ago

Laser Eye Surgery, Revisited 10 Years Later

jimmyswimmy Re:Astronomy, and general poor night-time results. (550 comments)

I've actually done exactly that, but not for that purpose. One eye is laser corrected to ~20/25 (degraded over about 15 years to about 20/35). The other eye can find the 'E' on the chart if you tell me which wall the chart is on. When I really need to, I put a contact lens in one eye (which gets the uncorrected eye to about 20/10). Otherwise I walk, read, work, type, drive, fly, etc. with what I believe is called monovision. It's easy. The world looks to me like normal, except that on the one ("bad") side I have very wide range of peripheral vision. I see whatever I focus on in good clarity.

It's amazing what your brain can compensate for. I can't wear glasses, though, that causes headaches.

about 2 months ago

Intel's Haswell Moves Voltage Regulator On-Die

jimmyswimmy Re:I am totally impressed (237 comments)

Not such a big breakthrough as you'd think. As you increase the switching frequency you can decrease the value of inductor and capacitors required. Last CPU supply I built - 10 years ago! - used 100 nH inductors at 300 kHz per phase. I skimmed the PSMA article but there was mention of MHz operating speeds, not at all unheard of these days, so the components ought to be much smaller. A 10 nH inductor and some hundreds of pF of capacitance seems very feasible without stretching the bounds of silicon technology at all.

about a year ago

Intel's Haswell Moves Voltage Regulator On-Die

jimmyswimmy From a former power supply designer - Neat! (237 comments)

That's some amazing work. The current state of the art in CPU power supply designs hasn't changed in 15 years. 12V in, low voltage out, and the output voltage has been moving lower and lower for years, with designs below 1 V. If you figure you had a few percent of tolerance in the early years when everything ran off 2.5V and that few percent remains constant, then at 1 V you have almost no room for slop. So there are a lot of output capacitors there, both those electrolytics (you always hear people complaining about them but they're CHEAP) and ceramics. The ceramics cost a fortune and you need a lot of them to get your tolerance down - the first half microsecond of a load step is entirely the ceramic capacitor's response, not the controller or anything else. Moving part of the VR onboard allows them to reduce the parasitics significantly and they can probably tolerate a little higher tolerance as a result, but moreover they can get rid of some of those ceramics in the whole system - ultimately many of those on the motherboard.

So this is taking a lot of cake out of company mouths. Analog, Intersil, IRF, ON, who else - manufacturers of controllers, MOSFETs. Inductors, ceramic and 'lytic vendors are all going to lose out a bit here. Potentially Intel can reduce the platform cost vs. AMD as well, which is interesting. There is still an onboard VR but it will be 12 - 2.4 V, wherever they think the sweet spot is for efficiency and size. And the first real change in this industry for a long time. Cool work.

about a year ago

Amazon: Authors Can't Review Books

jimmyswimmy Not sure about books (248 comments)

But reviews online are certainly corrupt. I don't use the star ratings for anything, unless an item only has a few reviews and all bad, and rely almost entirely on the BAD reviews for everything I purchase. If the bad reviews follow a common theme, it's a believable problem, and if I care about that problem vs. the price of the item, then I look for another item. Honestly I put less faith in the good reviews than the bad ones, especially when they're all glurge - no book, no product is perfect.

about a year and a half ago

Ask Slashdot: Tablets For Papers; Are We There Yet?

jimmyswimmy Nothing (180 comments)

The IEEE standard for papers is still a two-column format, and the paper is only downloadable in PDF, so the first problem is that the paper is completely unreadable on anything other than your printed paper. PDF sucks, and therefore Kindle, ipad, etc. will all suck. This is totally fixable but I haven't seen an application yet that does it.

Other problem is that I like to literally draw on papers as I read them... to check the math, to call attention to something, etc. Nothing I have seen has as simple and easy to use of an interface as a pen and paper. Relatedly, when I desire to draw up a schematic or other technical drawing documentation, I have found that trying to do it on a computer is so complicated that it ruins my train of thought. It's not hard, per se, but compared with a marker on a whiteboard it sucks. Take a cell-phone-camera picture afterwards and it's preserved and digitized for ever.

Perhaps if Windows 8 takes off, and touch screens become the norm for all computers, and we can get rid of this ridiculous abstraction of a "mouse", we'll be able to accomplish more of these tasks on a computer. Still, for brainstorming or putting simple thoughts to paper, I don't know if I can see a future use case where the tablet takes over from pen and paper/whiteboard and marker. Unless doing it on a tablet adds something, it's just not worth it.

about 2 years ago

Most US Drones Still Beam Video Unencrypted

jimmyswimmy So what? (138 comments)

So what if the video is transmitted in the clear? What does that get you...

- against a sophisticated enemy? They already know you're there (radar, DF on the transmitted signal). You're flying around in a racetrack centered on your target, so even without the video they know roughly what you're looking at. Problem is solved by an enemy air-to-air missile, or they ignore you and watch you watching them.

- against an unsophisticated enemy? They don't even know to look for the signal in the first place.

- against an enemy marginally capable of receiving the video signal? Use more channels, change encoding schemes so that COTS equipment can't pick it up so easily. Or yeah, encode it. But encoding video is fairly difficult considering the need to do it in realtime with limited processing capability and no tolerance for latency (and this is the real reason video is still transmitted in the clear - it's expensive to do anything but!). Or embrace it. Maybe your enemy can see you watching him - that can be played to an advantage.

about 2 years ago

Why Can't Industry Design an Affordable Hearing Aid?

jimmyswimmy Re:You can have 2: cheap, realtime, or resolution. (549 comments)

Just to hit on the basic point parent was discussing - that digital filtering is undesirably slow yet perhaps the best way to go...

I am not a hearing aid designer, but I've built lots of sensors. It would not be difficult to build an all-analog circuit with an ability to tune the gain on specific frequency bands via a digital potentiometer. When you have a lot of different, narrow bands it becomes challenging to fit all that in a tiny package. If it were just that, you could have the electronics for ~$50. Of course there's much more to a hearing aid than a few transducers and gain stages though.

about 2 years ago

Ask Slashdot: Rugged E-book Reader?

jimmyswimmy Re:Kindle Non Touch (126 comments)

I have a Kindle 3G and, although I love the device, it is not nearly as robust as parent suggests. Even with a [thin] protective device, the screen driver has died on me twice. Once while in a remote location where I had literally nothing else to read but tech manuals, and the other time it fell off my dresser. Both times I was seriously annoyed. Amazon is very reasonable about replacements, and the first was free, the second was half price. I am still in love with my Kindle but recommend a spare e-reader at minimum and strongly suggest a few lengthy printed tomes as backup, something you don't mind reading twice (perhaps a classic, a compendium of fiction, etc.).

more than 2 years ago

Dish Network Announces Prime Time TV With No Ads

jimmyswimmy ReplayTV (283 comments)

I had a ReplayTV years ago that did this, which used to be a competitor for Tivo until they lost the pricing war (didn't take long!). Actually until a few months ago I still used it regularly to tape standard def TV shows, but then my "lifetime" subscription ran out... (let THAT be a lesson to you)

Anyway they had two incredible features on these boxes, from around 2003 until the service shut down. The first was commercial skipping, which worked reasonably well. The second was the ability to share recorded shows. Several communities sprung up around this capability, so you could request a show that you had missed from someone else who had taped it.

Predictably they were sued and that did not help their already troubled business model. But it's not such a new thing for commercial skip to be available in COTS consumer devices. And man I miss it!

more than 2 years ago

HP Shows Off Power Over Ethernet Thin Client

jimmyswimmy Plenty of great uses for this (202 comments)

Receptionists, POS terminals, all kinds of good uses. This is the way I set up my computers at home - good desktop, cheap laptop with RDP. I could use one. Unfortunately no idea of the price. At $200 these will sell like crazy. At $400, may as well just get a big netbook. Knowing HP, they'll sell at $450.

more than 2 years ago

The Dark Side of Digital Distribution

jimmyswimmy Why update? (270 comments)

This is one reason why I rarely update anything on my Android tablet. I have a number of kids' games on there which never had many privileges when I installed them, so there's little security worry (plus it's only connected to my WLAN). What could "Draw by Numbers" possibly need to update to work better? The only "upgrade" I expect is them to remove pictures. My 3 year old is thrilled with the 10 or 20 different things she can draw on there, and that probably is limiting sales.

I only upgrade OS items now and disable the automatic upgrade checking for everything else. I'm sure I'll hear about why that's bad here. I think years of free and truly beneficial MS updates have confused a lot of us into thinking that an upgrade actually means what the word is defined to mean. Much like "gender" replaced "sex" I think the true meaning of the word "upgrade" is being replaced by something. Something not good.

more than 2 years ago

Study Hints That Wi-Fi Near Testes Could Decrease Male Fertility

jimmyswimmy Re:Wavelength (307 comments)

Touche, AC, and I agree with you, but as you point out (and I neglected to) the interaction between the RF generated by a microwave and water is a thermal reaction.

more than 2 years ago

Study Hints That Wi-Fi Near Testes Could Decrease Male Fertility

jimmyswimmy Wavelength (307 comments)

How is a signal with a wavelength of 5" (wifi is around 2.4 GHz, 2.4E9/3E8*39.37in/m=4.9") supposed to interact with a human sperm, which, according to wikipedia, is comprised of a head 5 um long and a tail 41 um long, all of which total 0.002 inches. These arguments never ever make any sense to me.

more than 2 years ago

DARPA Proposes Ripping Up Dead Satellites To Make New Ones

jimmyswimmy Re:Makes sense (186 comments)

Parent is exactly right. In the defense-sciencey world, there is a whole class of problems often called DARPA-hard. I think the term is one DARPA itself uses. My company recently missed out on an opportunity to bid a project for DARPA because we had an approach based on current technology which could be fielded very quickly. DARPA doesn't do that. DARPA does crazy, hard projects with the goal of advancing technology. This is definitely an area ripe for DARPA - it is a high risk, high payoff application.

Suppose this works - the cost of putting a new bird in orbit drops significantly. Rather than destroying a satellite that isn't working quite right, you could salvage it for parts the way we do a car. So first, you haven't wasted these space-qualified and tested components, but even better, you don't have to fly new ones up there. That's not just money, it's also time. You might be able to extend the effective lifetimes of various satellite constellations, such as GPS, Iridium and GLONASS, and thus improve reliability of such systems.

There's a fairly obvious flipside, as well - I don't know if there is international law on satellite ownership, but the law of salvaging seagoing vessels is quite clear - finders keepers. You sink a boat and I find it first, it's mine to sell - including its cargo. I don't know how this applies to space, but there is a pretty obvious (to me) parallel between a sunk boat and a grossly nonfunctional satellite. To clearly state my point: suppose a Russian spy satellite breaks, and we have this capability - we could take it and break it apart and do as we like to it. Of course if not done covertly the Russians would simply destroy one of ours, but it is interesting to consider the possibilities.

more than 2 years ago

Ohio Supreme Court Drawn Into Magnetic Homes Case

jimmyswimmy Re:Chose builder that gives you the lowest quote.. (462 comments)

Most dishwashers are held in place with exactly two screws. Wood screws are nicer than typical - most of the time I see drywall screws.

Otherwise you're absolutely right, you get exactly what you pay for. If you don't know enough to assess the property on your own, or you don't pay a qualified inspector (and even more rare - an honest and knowledgeable one) to tell you about the house and heed his warnings, you're stupid. Quality of materials and workmanship is not that hard to inspect by eye.

more than 2 years ago

Ohio Supreme Court Drawn Into Magnetic Homes Case

jimmyswimmy Re:Interesting problem (462 comments)

I don't think it's the cost of the materials to perform degaussing - a bunch of wire, a rectifier and a variac along with a field sensor ought to be sufficient. It's the knowledge of what you have to do, which most people don't have (present readers possibly excluded from the definition of "most"). More importantly it's the damage you might have to do to the house to get access to the beam. Suppose the beam is in a finished area? No way you can pay a contractor to open the entire length of the house and then close it back up for less than 5k, plus you may not be able to live in the house at the time. If you want to replace the beam that's easily another 10-20k, depending on way more factors than I am aware of.

more than 2 years ago

Does Italian Demo Show Cold Fusion, or Snake Oil?

jimmyswimmy Re:Fueled by pre-loaded hydrogen (479 comments)

If I remember correctly the palladium irreversably changes phase when you cram enough hydrogen into it. Palladium hydride has an alpha phase at room temperature and low hydrogen content. When sufficient hydrogen is absorbed by the palladium the crystal structure is permanently distorted. So you could detect that the palladium had been preloaded with hydrogen you ought to be able to detect it by measuring the resistance of the palladium after the test.

more than 2 years ago

Ohio Supreme Court Drawn Into Magnetic Homes Case

jimmyswimmy Interesting problem (462 comments)

When I have signed contracts to purchase things, I have had to sign waivers limiting liability. Those waivers certainly covered reasonable expectations and disclaimed certain possible defects. This is a terrible problem for both sides, because it is just completely unexpected. I have never before heard of a steel beam's magnetization causing such difficulty. TFA is pretty slim on the real effects they are experiencing. I wonder if this is just one of those pseudo-scientific problems (magnetism = evil?) or if it is a real problem, or if it's just my reading comprehension. It would be interesting to see what the field measurements actually looked like. You'd need a very strong magnet to affect a TV from any significant distance.

At least with smaller pieces of metal you can whack them a few times to re-randomize the magnetic domains. I don't know if that actually works for something large enough to support a building (you might have to hit it hard enough to damage it or the structure it supports). Depending on the alignment of the magnetic field it might be possible to form an electromagnet to cancel its field ("degauss" it). Or the structural members can be replaced and removed (I've done this in my house). Most of these options are pretty expensive (except for the first one where you hit it a lot with a hammer).

It seems unfair for me, as a homebuyer, to get stuck dealing with a house which was built with nonstandard components (in the form of a magnetic structural support). From the builder's perspective it seems like this would be something that they would have to eat and then go after the material seller for their losses, if they can prove when the magnetization occurred.

more than 2 years ago

Hurt Locker Lawsuits May Reach Canadians, Too

jimmyswimmy Big ISPs = larger number of defendants (159 comments)

In answer to OP's question, I suspect that the movie mafia are going after downloaders at large ISPs because the payoff is bigger - they get one process going through one legal department, and a number of names and addresses of suspected downloaders is produced, after which they send out ransom letters. At smaller ISPs, there are fewer targets to send letters to, so the cost is proportionally higher per target.

So in a sense, you could say that customers at smaller ISPs are safer, depending on the movie organizations' intent - if they want to make money off people and get a lot of big settlements to make news, they would focus on large ISPs and their customers. If they want to thoroughly scare people, they'll go after everyone, independent of the cost of doing so.

about 3 years ago


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