Most guilty people will immediately try to become the victim. Ignore the fact that I convince gullible people to buy junk that at best is useless and at worst will harm them. Ignore the fact that I use my medical degree to trick people. Look at the big bad corporation over here that wants to attack me. Ignore the fact that I am in the arms of a big bad corporation that airs my tv show and wants rating no matter what.

My problem with Dr. Oz is not that he appears to be a unethical charletan that will prostitute himself to any snake oil salesman who asks. My problem is, n the few shows I have seen, is that he actively is teaching his audience bad science. This is not surprising as doctors are not scientists. For instance, there was one show on fat where his depiction of fat was completely inaccurate. The demonstration was there to be visually exciting, but at the expense of any real science. I can imagine the people who saw it going to their doctor and arguing a point, thinking Dr. Oz is right, and their doctor is wrong.

It is entertainment. I agree that persons who are fundamentally entertainers and not seriously committed to medicine should probably not be the medical staff.

Why wouldn't a randomized subsample from 10M people get funded? The required sample size doesn't grow as the population does.

I may be responding to a troll here, but, no, the GP is correct. P-values are about probability. They're often used in the context of evaluating a correlation, but they needn't be. Specifically, p-values specify the probability that the observed statistical result (which may be a correlation) could be a result of random selection of a particularly bad sample. Good sampling techniques can't eliminate the possibility that your random sample just happens to be non-representative, and the p value measures the probability that this has happened. A p value of 0.05 means that there's a 5% chance that your results are bogus in this particular way.

The problem with p values is that they only describe one way that the experiment could have gone wrong, but people interpret them to mean overall confidence -- or, even worse -- significance of the result, when they really only describe confidence that the sample wasn't biased due to bad luck in random sampling. It could have been biased because the sampling methodology wasn't good. I could have been meaningless because it finds an effect which is real, but negligibly small. It be meaningless because the experiment was just badly constructed and didn't measure what it thought it was measuring. There could be lots and lots of other problems.

There's nothing inherently wrong with p values, but people tend to believe they mean far more than they do.

You're not getting what he was saying.

I do get what he's saying. What neither of you seem to grasp is that the size of the target isn't as relevant as you think, because you have to null your horizontal velocity regardless of the size of the target. It doesn't matter whether you're stopping on a postage stamp or anywhere in a given block - either way you still have to stop. It's the stopping that's problem, not the deciding where to stop. Stopping is very difficult for the Falcon 9 because it's T/W ratio is so far out of the optimal range and a larger target area won't make it all that much easier.
 

Though if they're that good at targeting, maybe programming up an adaptive 'catcher' robot would work? I'm thinking of something along the lines of 3 arms that have a range of motion, and when the rocket's within a few feet, they gently 'grab' the rocket using shaped and padded interfaces(I'm picturing a semi-circle matching that of the rocket) and provide stability.

That's "good at targeting" a couple of orders of magnitude better than what they've demonstrated to date (which is, pardon my french, already pretty fucking amazing). You're talking about some kind of articulated arm (which can survive being essentially inside rocket exhaust)... Which is, quite frankly, makes things much harder and more complicated and introduces a metric buttload of additional possible points of failure. Much easier to simply re-engineer the throttle valve.

IMHO, if more of the horizontal velocity was shed earlier, It'd be easier to stay balanced at the end.

At the cost of increasing the difficulty of targeting the landing, and still having to null any horizontal velocity due to the wind. TAANSTAFL.

I seriously doubt it. I don't see how location reporting for a payment transaction in which location data is irrelevant could possibly pass Google's privacy policy review process. Collection of data not relevant to the transaction is not generally allowed[*], and if the data in question is personally identifiable (mappable to some specific individual), then a really compelling reason for collection is required, as well as tight internal controls on how the data is managed and who has access. I don't see what could possibly justify it in this case, and I can see a lot of risk in collecting it.

FYI, Google product teams have to develop privacy design docs for all new products, and the designs have to be reviewed by the privacy team (or their delegates) and pass the privacy review before they can be launched. Although Google set these processes up before the FTC settlement, I believe they became part of the consent decree and are now mandated by the FTC and validated in regular audits, so Google can't skip or violate them without potentially-significant consequences.

Disclaimer: I'm not a Google spokesperson and this is not an official statement. It is my personal perspective on the process and requirements. However, I'm a Google engineer who's been involved in launching privacy-sensitive products, so I think my perspective is accurate. I also do security reviews of Google projects, which sometimes touches on privacy issues (though privacy review is separate from security review, as it should be).

[*] Just to head off a likely riposte: No, StreetView Wifi collection and the Safari do-not-track workaround are not counterexamples. They predated the privacy review processes and, as I understand it, were part of the motivation for establishing the processes.

As opposed to what? Cremation? Burial in a box at temperatures well above freezing? You can't seriously argue that this approach makes it less likely that she could be repaired and restarted at some point in the future than typical corpse disposal methods.

The rest of what you say is generally true, although a larger target *would* help. The advantage of a larger target is that, while you still have to zero your horizontal velocity, you don't have to zero it anywhere terribly precise.

Yeah, you do. Given the narrow footprint and the low CG of the vehicle, if the horizontal velocity wasn't as close to zero as you can get at touchdown - it's very likely to tip over. (Even if you don't damage the landing legs in the process.) The upper part of the vehicle isn't heavy, but it has a very long lever arm.
 

You can pick an optimal set of thrusts that results in the correct orientation and velocities (horizontal and vertical) without worrying overmuch *where* that series of thrusts has you touching down.

In the end, that makes far less difference than you think because while you can reduce the amount of horizontal velocity that needs to be nulled you cannot eliminate it. (Not without launch criteria that include "near zero wind at the recovery site", which is beyond impractical.) The result is, with the current vehicle, you still have to null horizontal velocity at the last second before touch down. The basic problem is that the vehicle is badly designed for what it's being asked to do.
 

. Both attempts so far clearly demonstrate the ability to do an excellent good job of targeting a (relatively) tiny barge, but currently, if the rocket would come down even 100' (30m) to one side of its target spot, it needs to induce a horizontal momentum (which requires leaving a vertical attitude as well, it can't just translate sideways) and then null that momentum at the right moment (and fix its attitude). That's hard.

Both times they've hit the barge almost dead center - I fail to see how that's an arguement for a larger landing area since neither failure was caused by the landing area being too small. Both vehicles would have crashed regardless of the size of the landing area due to control system failures. (Attitude control on the first, throttle control on the second.) That's what neither you nor the OP seem to grasp.

The evening slowdowns don't affect Netflix streaming, for me.

Kind of makes me wonder if using the barge as such a small target is contributing to the hard landings, simply because it's such a tiny target relative to the area that the rocket has to come down on

Since the first attempt hard landed because it ran out of attitude control gas, and the second hard landed because of a control valve problem... how would a larger target have helped? In case of the first attempt, you've still got to control your attitude regardless of the size of the field. In the second, the size of the field is irrelevant if you can't properly control the vehicle in the first place.

Seriously, don't be misled by the frantic activity in the final seconds of the most recent attempt. That burst of activity was the vehicle attempting to null it's horizontal velocity and then trim it's attitude before landing - something it has to do regardless of the size of the field.

The basic flaw in the landing sequence isn't the size of the target, it's the design of the vehicle. Its minimum T/W ratio is well over unity at landing, meaning it can't hover, can't ease itself down, and you have to take great care to not end up with positive vertical velocity. The only way it can land (with any reasonable sized target) is to approach at high speed, then at the last second try to null horizontal velocity without excessively reducing vertical velocity (I.E. bouncing), followed by a return to vertical and touchdown.

You could avoid this by having a circle of paved ground a quarter to half a mile in diameter - but that's not cheap to build or maintain given the need to resist a rocket's exhaust. Long term, given that the tests are essentially free*, it's cheaper and easier to figure out how to land precisely on a smaller target.

* The first stage is bought and paid for by the launch customer - and so long as the added equipment for landing poses no undue risk during ascent, they don't care what happens to it after separation.

That's true, but I see it as a matter of degree. Windows does a lot more, sure, but FreeBSD is still doing some HTTP parsing in a kernel module.

Exactly this. I'd like to think that there's an air gap (ahem) between the avionics and passenger networks, and that it's impossible to access the avionics system from the passenger compartment. I'd also like to think it doesn't rely on security through obscurity, like "we run our API server on port 81 instead of port 80, ha-HA!". Come on, Slashdot: we have to have at least one aerospace engineer in here, don't we?

It sure seems that if a larger landing area was available, so that the rocket didn't have to lean so far to adjust to a very small target and thus could prioritize staying vertical, it would be able to land successfully.

No so much as you might think - you still have to trim and eventually null your horizontal velocity, and null any horizontal residuals arising from trying to remain vertical. It's a complicated problem, even if you're just aiming for an arbitrary landing spot in a larger landing area.

On top of that, the crash seems to have been caused not by prioritization, but by a control valve operating sluggishly causing the response time to go out of limits. Even if you're just accepting a landing wherever you're coming down, if the control system gets out of phase you're screwed.

FWIW, I think those are perfectly plausible explanations. I mainly meant wanted to frame the GP's own opinion as a formal test case; that's a copy-and-paste of what he wrote.

That test fails. What if it costs $50 per night for the bunk-bed and the rest is subsidized through external donations?

And if that $200 turns into renting clinic space and buying supplies to provide free medical care to poor children?

My point is that the answer to these questions is never simple, and if you think you've found a simple definition that neatly covers everything, it suggests you're likely missing something.