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Comment: Re:So.... line of sight only? (Score 2) 96

by ceoyoyo (#49523343) Attached to: Optical Tech Can Boost Wi-Fi Systems' Capacity With LEDs

The point is that it's line of sight. You have to be directly under the emitter. So, for example, you could stick one over every chair in the airport. Everybody gets their own bandwidth, no interference.

The trick in the article seems to be a system where you can switch between the optical units and regular wifi if you lose contact.

Comment: Re:Three puzzles (Score 1) 208

by ceoyoyo (#49496861) Attached to: Social Science Journal 'Bans' Use of p-values

I assume you're getting at multiple comparisons because you said "he measures many things."

You're right, the researcher should correct his p-value for the multiple comparisons. Unfortunately, alternatives to p-values ALSO give misleading results if not corrected and, in general, are more difficult to correct quantitatively.

Comment: Re:Mis-use=reviewer don't do their job (Score 1) 208

by ceoyoyo (#49496837) Attached to: Social Science Journal 'Bans' Use of p-values

Your 95% confidence interval (roughly*) indicates an interval containing 95% of the probability. The p-value indicates how much probability lies within a cutoff region. What most people do with a 95% CI is look to see if it overlaps the null value (zero, or the mean of the other group, for example). The p-value gives the same information, except quantitatively.

* yes, Bayesians, technically the 95% credible interval, from a Bayesian analysis, contains the area of 95% probability. The confidence interval, technically, isn't quite the same thing. Practically, in the vast majority of cases, the two are either mathematically equivalent or equal to within a large number of decimal places.

Comment: Re:What's the problem? (Score 1) 208

by ceoyoyo (#49496035) Attached to: Social Science Journal 'Bans' Use of p-values

There really aren't any good ways to measure those other effects. If you knew how your experiment was biased, you'd try and fix it.

Criticisms of p-values usually fall into two groups. Some people believe that p-values are bad because some people interpret them as the false positive rate. Personally, I think that's a problem with some people, and not p-values. The other criticism, which is particularly prevalent in social sciences, epidemiology and some of the squishier medical-type areas, is that if you get a non-significant p-value you discard potentially useful results. The usual proposal (which is probably the situation in this case) is to use confidence intervals. That way you can see all the area where your confidence interval is not overlapping zero! I have two objections to that. First, CIs are simply calculated from p-values and vice versa - they're really the same thing presented differently. Second, the reason you discard your result (or save it for a meta-analysis) if you get an insignificant p-value is because your data has been ruled insufficient evidence. Looking at CIs and marvelling at all the potentially meaningful area between them is just softening the p 0.05 rule of thumb. Incidentally, the false positive rate people suggest doing the opposite - using p 0.01 or 0.001 as the threshold for significance.

Comment: Re:Students + Anonimity (Score 1) 234

by ceoyoyo (#49489491) Attached to: Can Online Reporting System Help Prevent Sexual Assaults On Campus?

That's a good way of putting it. It might actually be a decent tool for the cops to use. The difference being that the police and courts are (supposed to be) knowledgeable about the law, trained in its enforcement, and accountable for their actions. The university offices in charge of these things, not so much.

On the other hand, if you're not even willing to walk down to the campus police station and file a report, any prosecution probably isn't going to go very far anyway.

Comment: Re:all in the implementation (Score 1) 113

"The reason Boeing went for this was to reduce weight, power consumption and complexity."

No, it's not. They most certainly are not running the entertainment system on the same wires as the avionics. The avionics system is a real-time network that is different at a very low level. The FAA exception allowed Boeing to connect the two networks at a single point, using a "network extension device."

Using TSO is like kicking a dead whale down the beach. -- S.C. Johnson

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