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Comment: p-value research is misleading almost always (Score 5, Interesting) 208

by SteveWoz (#49495363) Attached to: Social Science Journal 'Bans' Use of p-values

I studied and tutored experimental design and this use of inferential statistics. I even came up with a formula for 1/5 the calculator keystrokes when learning to calculate the p-value manually. Take the standard deviation and mean for each group, then calculate the standard deviation of these means (how different the groups are) divided by the mean of these standard deviations (how wide the groups of data are) and multiply by the square root of n (sample size for each group). But that's off the point. We had 5 papers in our class for psychology majors (I almost graduated in that instead of engineering) that discussed why controlled experiments (using the p-value) should not be published. In each case my knee-jerk reaction was that they didn't like math or didn't understand math and just wanted to 'suppose' answers. But each article attacked the math abuse, by proficient academics at universities who did this sort of research. I came around too. The math is established for random environments but the scientists control every bit of the environment, not to get better results but to detect thing so tiny that they really don't matter. The math lets them misuse the word 'significant' as though there is a strong connection between cause and effect. Yet every environmental restriction (same living arrangements, same diets, same genetic strain of rats, etc) invalidates the result. It's called intrinsic validity (finding it in the experiment) vs. extrinsic validity (applying in real life). You can also find things that are weaker (by the square root of n) by using larger groups. A study can be set up in a way so as to likely find 'something' tiny and get the research prestige, but another study can be set up with different controls that turn out an opposite result. And none apply to real life like reading the results of an entire population living normal lives. You have to study and think quite a while, as I did (even walking the streets around Berkeley to find books on the subject up to 40 years prior) to see that the words "99 percentage significance level" means not a strong effect but more likely one that is so tiny, maybe a part in a million, that you'd never see it in real life.

Comment: Re:Math author dies rich... (Score 1) 170

by dario_moreno (#48641615) Attached to: Calculus Textbook Author James Stewart Has Died
Yes, I bought some of the Landau and Lifchitz books at the time for $3, they are now worth $150 at Springer...Younger self should have believed in himself more. Funny to see that now we can download 5000 C64 games for free, not to mention MAME roms, a good PC is $500, (at the time, $30 per game, a decent PC was $3000 of the time) but those books are 50 times more expensive...and the content still worth it.

Comment: timing - which year (Score 2) 72

by SteveWoz (#47628049) Attached to: Expensive Hotels Really Do Have Faster Wi-Fi

I travel a ton and stay in dozens of different hotels every year. Domestically, and in maybe 50% of the foreign cases, the high priced hotels had worse and slower internet up until a couple of years ago. For the last 2 years they have gotten better, on the average. Oh, I was in a 5-star Vegas resort last night that had horrible bandwidth. In the past, my joke was accurate that the difference between a Four Seasons (just an example) and a Super 8 is that at the Super 8 the internet worked and was free. The most important thing to me in a hotel is computer use. The fancy suites in major hotels are often set up for entertaining friends and DON'T even have a computer desk. I ask my wife to book me into Super 8's whenever possible.

Comment: Instead of a degree, try this (Score 1) 637

by johnnyb (#47619807) Attached to: Ask Slashdot: "Real" Computer Scientists vs. Modern Curriculum?

I actually noticed this trend about 8 years ago, and wrote a book to solve it. The book is called Programming from the Ground Up. It is a Linux-based assembly language book, but also teaches a lot about systems programming in general, but without being too technical.

For the other CS-oriented stuff that they don't teach, the two books you should get are how to design programs and Structure and Interpretation of Computer Programs. After that, I have written a series of articles to apply those ideas to "real" programming languages on IBM's developerWorks. You can find links to them here.

Comment: Re:The question to me seems to be... (Score 1) 148

by SteveWoz (#47357639) Attached to: Lawrence Lessig Answers Your Questions About His Mayday PAC (Video)

End goal: change the constitution. We need a start. It's easy to see how hard this will be and to give up early, but some of us feel the imperative to fight for it. We can change things. The vast will of the masses (corporation political donations are not equivalent to the free speech we enjoy as individuals) needs to be strategically gathered. Critical mass could take decades, as with things like gay marriage.

Comment: Early Detection (Score 5, Informative) 22

by johnnyb (#46445141) Attached to: Sniffing Out Cancer With Electronic Noses

The problem with early detection is that many diseases are actually benign in their early stages, and, when detected, their detection can actually cause more harm for the patient. For instance, early cancer detection increases the likelihood that the patient will start chemo. Some cancers wind up being handled by the body, but *all* chemo treatments harm patients. So, early detection sometimes leads to more harm than benefit (plus an unfortunate issue with "success" rates - the cancer treatments get to include in their "success" count cancers that the body would have cleaned up anyway).

Comment: Re:Still profitable.. (Score 1) 132

by johnnyb (#46413133) Attached to: Oregon Withholding $25.6M From Oracle Over Health Website Woes

"Or are those contracts written so horribly that the company gets paid for a nonfunctional product?"

The problem is that a lot of these types of contracts are written with a clause such that launching them publicly is an implicit acceptance of the project as a finished product. So, since they at least tried to launch it, that means that the project is "finished", and everything else is billed hourly on top of it.

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