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Comment: Re:Overly broad? (Score 1) 377

by penguinoid (#48185511) Attached to: Soda Pop Damages Your Cells' Telomeres

OK Mr Anonymous Unverifiable PhD, what if you do a different study? In this new study, thousands of studies are done, and show results with p-values p-1, p-2, p-3, .... However, the results of most of these studies mysteriously vanish, lets say a bunch of them aren't reported by the researcher, and a bunch more are not accepted by any journal of note, and vanish into obscurity. The vanishing studies aren't random, but the vast majority of them are ones where the null hypothesis were not rejected. Besides this, the journals select for the most "interesting" studies, which for this example let's say it means that the results were surprising and in contradiction with either conventional wisdom or previous studies. Let's call the remaining p-values tainted-p-1, tainted-p-2, tainted-p-3. These p-values are nothing new, but rather a subset of the original set. Let's say only 8% (the acceptance rate of Nature) of the original studies make it to this second group, biased towards the more "interesting" studies with mostly positive results.

So my question to you is, are you equally as confident in the hypotheses from the smaller subset of studies as you are in the hypotheses from the second set? And what, if any, is your mathematical reasoning behind this answer?

Comment: Re:Overly broad? (Score 1) 377

by penguinoid (#48183853) Attached to: Soda Pop Damages Your Cells' Telomeres

The p-value does not measure the confidence people have that the hypothesis is true. The p-value is the probability that the given results support the hypothesis merely as a result of random chance. This means that every sane person considers the probability of the hypothesis being false as higher than the p-value, sometimes several times higher, depending on circumstances.

For example, if someone tested 20 hypotheses with the same dataset, and only reported one with a p-value of 4%, it is almost certain that the results are meaningless, as per the linked comic. When you factor in the bias toward reporting interesting experiments with statistically significant support for the result, both on behalf of the researcher and the publishing journal, some would consider it generous to have even 20% confidence in an "interesting" result with 4% p-value.

A p-value of 5% is the absolute minimum allowed in most scientific professions, although several require an even smaller p-value. The only reason p-values that large are even allowed, is because of the economics (and sometimes ethics) of performing experiments. Eg it is more worthwhile to do 10 studies with sample size 100, and then 1 study with sample size 1000 to verify the most interesting result, than to do a single study with sample size 2000.

Comment: Re: a quick search (Score 1) 273

by penguinoid (#48181427) Attached to: No More Lee-Enfield: Canada's Rangers To Get a Tech Upgrade

I should like to hear your proposal for gun parts made in anything other than 3 dimensions.

Also note he said a 3D scanner, not a 3D printer, although I'm fairly certain that merely knowing the shape is not sufficient since how it got that shape lends a lot to its mechanical properties.

Comment: Re:Yeah yeah (Score 1) 109

Ignorance of the law has never been an excuse, in tradition dating back thousands of years. Though nowadays everyone including the judge and lawyers are ignorant of the law an it is not humanly possible to know all the law. Anyhow, who ever heard of a thief getting off because he claims he didn't know *stealing jewelry while wearing a tuxedo* was illegal (the law never mentions jewelry specifically nor tuxedos, does it?), and promised from now on he won't do exactly that? That's about as believable as those cops claiming that stealing *people's private communications using Stingray towers* was not illegal, and then being told OK but don't do it again. I mean, they might have some sort of case if it weren't for the towers impersonating real ones.

Comment: Re:You want an idea? How about we fund NASA? (Score 1) 348

First organization to establish a manned colony for one year owns wherever that colony is, up to an area of 10 million square miles.

I think you mean, first person to set up space snipers to ward off the competition, gets all the space territory they want.

Is a person who blows up banks an econoclast?