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Comment: Statistics analysis (Score 1) 246

by davolfman (#48408209) Attached to: Big Talk About Small Samples
Basic stats Margin of Error for 95% confidence on the first stat is plus-or-minus 12.2%
Same confidence is plus or minus 12.4% on the second.
.23*47 = 10.81 at least 10 successes and failures expected (just barely)
.3*54 = 16.2 at least 10 successes or failures

Randomness of the sample is unknown. This could be a problem.

We have less than 10% of the population so we don't have to worry about a sample that's too large.

Conclusion: if the sampling method is reasonably random then assuming a normal model is reasonably valid.

Unfortunately both values are within .57 standard deviations of eachother. There is a very good chance with sample sizes this small that both are recording the same population parameter with different sampling errors. Larger sample sizes would reduce the standard deviation (proportional to inverse square root of number of sample) and make it easier to say that there was a definitive difference between the two.

Comment: Re:You'd think they'd have learned their lesson. (Score 1) 530

by davolfman (#41902647) Attached to: Apple Considering Switch Away From Intel For Macs
True, but... Multithreaded design is hard (except in shell scripting). Watt usage will be important for the vast majority of the market, namely laptops and smaller, and even now power is getting expensive enough to move me to my laptop for all light usage. Streaming instructions are best for problems that would already benefit well from multiple cores and OpenCL in many cases. Not saying your wrong, just adding some counter detail.

Comment: You'd think they'd have learned their lesson. (Score 2) 530

by davolfman (#41899941) Attached to: Apple Considering Switch Away From Intel For Macs
Not to knock ARM, but A: I don't know that they have a design for a desktop processor yet (most of their designs seem to be in the Atom/Bobcat realm tops) B: With the absolutely massive amounts of money Intel put's into their Tick-Tock development cadence they have both pretty much the most optimized desktop/laptop architecture their is, and probably the most significant process advantage in the history of semiconductors. Honestly given the way both Intel and AMD have been able to use out-of-order execution and pipelining to achieve multiple Instructions Per Clock and multi-gigahertz clocks on a CISC-backed-by-microcode architecture I'm not convinced RISC actually has an advantage in practice. In addition Apple is stuck with the foundries, the same as pretty much anybody but IBM, and so pretty much CAN'T begin to produce a chip that will compete with Intel's best when comes to raw performance or performance-per-watt. For those reasons this would be pretty foolish any time in the next several years. Even if a decade from now they can work past it they will still be stuck fighting off the suspicion that they don't have the advantage they claim to, the one that more or less was true at the end of their use of PowerPC chips.

Comment: Re:Flint is extremely sharp (Score 1) 287

by davolfman (#38276512) Attached to: Ask Slashdot: One Framework To Rule Them All?
Could you provide links and details? Mostly to satisfy my curiosity. Steel is NOT a singular substance. If you vary the formula you get different hardnesses and different grain sizes and structures. And last I saw some flint it looked pretty grainy. I could easily believe that obsidian could take a sharper edge than surgical steels for at least a single cut (especially since it looks like they may be formulated for hardness and corrosion resistance resulting in large grains). I bet you though that a good high-vanadium alloy or similar like the stuff in some high-end pocket knives probably attains a sharper edge than surgical steel with a good sharpening technique. And after a few cuts it probably has a better edge than the obsidian. Absolute sharpness is probably NOT the overriding market consideration for surgical steels. It might be worth noting that Wikipedia's pages for steels seem to be much worse than they used to be.

Comment: Less than useful - it uses EBL! (Score 1) 142

by davolfman (#37735714) Attached to: Table Salt Could Help Boost HDD Storage Density By a Factor of 5
Honestly why does no one seem to notice the part about this where the salt is being used in a "photo" resist for Electron Beam Lithography. That's beam - as in every single surface feature needs to be drawn by a beam of electrons one at a time. The amount of time and expense that would go into the construction of even one 3.5" platter is staggering. Yes it's cool and all but only a military application or James Bond could justify it; ever. An improvement to a mass-produced technology that makes it impossible (and I do mean impossible unless someone comes up with a magical quantum mechanical wave interference pattern that forms the magnetic regions all at once or something) to mass produce is no improvement at all.

Comment: Re:Someone's math is wrong (Score 1) 487

by davolfman (#35985224) Attached to: Department of Justice: FBI Too Focused On Child Porn
Removing a market is blatantly impossible. The market is always the larger target. For example: prohibition, the war on drugs, filesharing, knockoff merchandise. You can't even always take out the producers but you'll never get more than an endless stream of arrests out of targeting the market.

Comment: You can tape my punchtape when you pry it... (Score 2) 117

by davolfman (#35371426) Attached to: UK Controllers Say Air Traffic System 'Not Safe'
Am I the only who seems to notice that the old system apparently ran off ticker tape somehow? WTF! How do you even make that work? If these people have been working on such a system that long no wonder they have trouble training them to a new system, it must all be reflex by now like driving a stick shift.

Comment: Re:Top Ten Things to do with FBI Tracking Devices (Score 1) 851

by davolfman (#33839794) Attached to: College Student Finds GPS On Car, FBI Retrieves It
How about use the FCC ID on the thing to look up the manual and other related documents. Apparently it's meant for surveying work originally. "The GRS receiver is a single-frequency, GPS+GLONASS L1 L2receiver and hand-held controller built to be the most advanced, compact, and portable receiver for the GIS surveying market. An integrated electronic compass and digital camera make the GRS an all-purpose, GIS field mapping unit."'O9EQ2438F-M'

Money will say more in one moment than the most eloquent lover can in years.