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Comment This is the classic "expert problem" (Score 1) 297

This is not about being pressured to make a shorter estimate, it's about how confident you feel about whatever "real" estimate you've made (even if that estimate never gets past your manager).

From Taleb's "Black Swan" which I believe Kahneman was quoting in FT&S, the more information you have the more confident you will feel about your estimate, even though your estimate will not improve with additional information.

Taleb makes the distinction that some areas have no black swans (totally unforseen / unforseeable events). He calls this 'mediocristan'. There is much less of an expert problem in this area. Then there are areas where there's the possibility of a black swan. He dubs this 'extremistan'. Expert predictions are much more likely to go awry because, well, something unforseen has happened. In either case, the more information we have, the more confident we will be of our predictions but we are not sensitive to when things shade from mediocristan to extremistan.

Comment Re:They Saved The World (Score 1) 352

I don't disagree with Truman's decision either.
My view:
The allies were already firebombing cities in Japan. The first atomic bomb, as Truman and advisers were considering it, wasn't so much different as just much more efficient.
Also, the allies had already been through the air war against Germany, which started out as an attempt at precision bombing of military industrial targets and devolved into carpet bombing, explicitly so in the case of Brit. bomber command, incidentally so in the case of the USAAF. But by the time the firebombing started in Japan, the allies were already well aware of what they'd been doing in Germany; this was just more of the same, but more efficient. An atom bomb would be another step towards efficiency. Attitudes about civilians were already numbed.

Further, although they weren't publicized, I'm sure Truman and advisers were well aware of Japanese brutalities, driving even less consideration for Japanese civilians. I expect this also factored against accepting a conditional surrender.
The battle for Okinawa had just happened, with high allied casualties. The forecast for allied casualties in a Japanese home islands invasion is certainly influenced the choice of firebombing, but it would have been equally valid for atomic bombing.

I don't see it so much a dichotomy between 'atomic bomb' and 'invade' but more one between "invade now" and "bomb first". 'Bomb first' became 'firebomb' (decision made at operational level as I remember). Once the atomic bomb became available, yes, the decision went to Truman, but, well, there was already firebombing, and this was just another step along the road...

Comment China != US (Score 1) 857

And you think China and the US were comparable in the 30's?
I'm pretty sure the Japanese didn't either.
They had an opportunity (European colonial powers either occupied or on the ropes) and a problem (US forces could interdict them from bases in the Philippines). So: a gamble. Try to take out a good portion of the US Pacific fleet for naval supremacy, then take out the Philippines, and *then* start acquiring European colonies (focus there because that's where the raw materials, either as minerals or as plantations, were.). It looked like a reasonable bet because the US looked to be somewhat embroiled in the European war (yeah, OK, that was FDR's doing) *and* they had a promise from Hitler that Germany would support them if they became embroiled in a war. That promise seems to have come about (read Shirer's Rise&fall: this from captured Nazi documents) because the Nazis were trying to get the Japanese to attack the USSR - but the Japanese had a non-aggression pact with the Russians, which they were abiding by.

Comment Not 'Kiwis' (Score 1) 329

Maybe folks in Aus call folks from NZ 'Kiwi's', but the people who actually live there are more likely to self identify as NZ-ers ('en-zed-er' for those who pronounce the letter 'z' as 'zee').

>>I'm an Aussie (the bigger brother of the Kiwis)
I'm also pretty sure they don't think of Australians as 'big brothers' either - at least I never met one there who expressed that opinion (was there for some months on an extended motorbike holiday).

To re-phrase part of your comment: ...Having said that, I'm from the US (the bigger brother of the Ozzies) and...
Grates on the nerves, doesn't it?
And, no, I don't actually think that, but give the NZers a break, would ya?

Comment Alzheimers epidemic (Score 1) 542

There seem to be a lot more cases of Alzheimers out there.
Part of the progression of that disease is becoming delusional, so anti-psychotics are not an unreasonable thing to try.
As to whether they actually help, well, who knows? There isn't even an agreed-upon model for the disease.

Comment It did downsize - then there was Korea (Score 1) 336

Korea 'saved' the Truman administration from having to permanently bring the military back to pre WWII peacetime levels. Achison made a comment to the effect at the time. Achison was also the prime mover in, essentially, warping George Kennon's policy of 'containment', a non-necessarily--military push back against communist expansion (think Marshall plan) into a definitely-military policy. This then drove a military re-buildup (build-down had already happened to a great extent, one of the reasons the NPK walked all over US forces in their first push southwards. Interesting (to me at least) that something so pivotal gets forgotten. Given all the horrible things the US did to SK after Japanese evacuation (Halberstram got it 'way wrong) it's not surprising that it was essentially buried. Oh, and this is when US advisers first get sent to VietNam. One could argue that further involvement in VN was driven by Achison's version of Kennon's plan, and that the 'domino thesis' was just another way of stating this same thing. There was clear feeling against doing anything to save France's (or Britain's) pre-WWII colonial holdings (have a look at the Congressional Register, plenty of public speeches), so without this military containment policy, we'd have let it go to the nationalists.

Comment Congresscritters fly - a lot (Score 1) 647

Seems to me we have our passenger "bill of rights" (not about this, but about not being bumped, delays, etc.) primarily because the folks who make the laws fly a lot.

But they're all OK with this (naked/radiation vs grope)?

What if scanner pictures of congresscritters started appearing on the web? Or even convincing fakes.
I don't have much body modesty, but would feel pretty invaded (and pissed off) if it happened to me. I would guess that most congress folks have more body modesty, and would be even more pissed off - and they make the laws.

So, given that the TSA isn't actually deleting all the photos, and there are already incidents of TSA agents snapping photos of the screen with their cellphones, isn't it just a matter of time until something like this happens?

Comment The problem with restarting rare-earth mining... (Score 1) 738

...is that it takes capital. Capital that could be lost if the Chinese suddenly restart exporting it for cheap. So... who's going to risk it?
BTW, the Saudis have been playing this same game with alternative energy - lower the price of oil every so often so anyone trying to build solar energy or wind production is suddenly relatively too-expensive. Companies go bust, investors lose. Third or fourth time that happens, investors shy away.
So... one thing the congress-critters could do is establish a set of *base* RE prices, for, say, the next fifteen or twenty years. Fine to import it, but it's taxed up to the base price. This would allow investors to put money into RE mining with some chance of not getting screwed by a Chinese turn-around. This will get more private money into RE extraction more quickly, and the Chinese *may* play the on-again off-again game just like the Saudis, for the same reason. They can see how well that's been working for the Saudis and may want to try doing the same thing.

Given that the Chinese aren't sending any RE to the US right now, it'd be hard for them to complain about a move like this. Longer term, if it works, which it should, we could use this as an example of what to do with oil prices (establish a base) to give alternate energy investors some confidence.

Comment Re:Hunters and responsibility (Score 1) 1141

I'm not currently a hunter, but was raised in a hunting / shooting family (mostly skeet, which, for the uninitiated is basically shooting small clay frisbees as they fly by)
I live in a town that restricts hunting (only allowed with permission of landowner, and most town residents are irrational enough about guns / hunters that there isn't much permission, not permitted on town lands - and you can't shoot within 500' of a residence in any case). One of the Boston exurbs, BTW.
So... in spite of there being coyotes around we have a deer overpopulation problem.
The kicker is that we're in a Lyme disease area - and there's been a lot of it in the last few years (many of my neighbors have had it). It's carried by ticks that live on both deer and mice (different life phases). So it's not just the deer, but there have been some studies in which culling the deer population brings the tick population down more-than-proportionally. BTW, the ticks are pretty tiny, hard to see and a lot of the victims are kids.
So we need a deer population cull.
My neighbors are still pretty irrational about guns, but I've been having luck turning those attitudes around with a "it's for the children" appeal.
So we'll see what happens.

Comment Re:Harshness is all about color temperature (Score 1) 859

By the way -- how many Slashdot articles (like this one) are we going to have full of people trying desperately to come up with a way to justify their decision to spend *way* more money in electricity and increase emissions because they're too lazy or stuck in their ways to merely change their lightbulbs?

I think the point here might be that CFLs need to be labeled for PF (or the utilities need to pony up for actual power meters).

Utilities are now getting hit with being able to bill for less power then they generate (and consumers are using a bit more power than they think). Meters that measure real power are (or at least were - anybody current on this stuff?) expensive. AFAIK up to now most electricity consumers with both high usage and low PF are industries (electric motors) - and the utility would meter actual power usage there.

Many power utilities hand out rebates - it might be useful for them to specify a "minimum PF" for CFLs qualifying for the rebate. This'd sidestep the issue of explaining to the general public what PF is (you try it sometime) and let the utilities encourage lower power usage.

Up to this point, I'd guess that the major low-PF item in residences and light commercial is PC power supplies. There are high PF PSs appearing, but AFAIK, these aren't appearing on mass market gear (i.e. Dell).

All that said, I use an incandescent "wall wash" lamp behind my monitor. I'm susceptible to migraines and seem to have more of 'em with any kind of fluorescent in the same room as my monitor. I'm sure there are CFLs out there that'd work fine for me but the process of finding the bad ones is a bit tough on me. Anybody else got the same problem - and a solution?

Comment simple mechanical things (Score 2, Informative) 1114

Nobody here seems to have mentioned windage. The far-from-centerline parts of your crankshaft tend to pick up streamers of oil, which causes internal drag.

Engine designers attempt to limit this as much as possible with something called a "windage plate", but, for over-the-road cars, it's a bit of a compromise. There are height constraints on the engine, so the oil pan can be only so large, and drivers don't want to be messing with their oil on a regular basis, so efficiency loses out a little bit when they pick a "top" oil level. Try not filling you oil up to that level. Your car will run fine with the level at the "low" marker on your dipstick and you can reduce windage a bit, which should increase mileage.

You'll need to check your oil level on a regular basis, and, of course, there's no advantage in a dry-sump engine - but I don't think any current autos have those.

While I'm on reducing internal resistance, think about using a lower weight oil, that will keep viscosity at high temps. Both Mobil One and Amsoil are good at this.

The notion here is that another point of resistance in your engine is the oil in your main bearings. These are "plain" bearings, which are actually "oil wave" bearings in that the crank actually rests on a hydrostatic wave. You don't need more viscosity for this than the viscosity of the spec'ed oil at max temp. Better to get an oil that starts out pretty close to this viscosity and then stays there.

Oh - and nobody's mentioned cleaning injectors. Yes, they clog, and they don't all clog at the same rate, so you end up with some cylinders running richer than the others. Not good for max power - or efficiency. Cheap partial fix: start using Techron. Complete fix: take 'em out and send to a specialist shop (note: talk to folks about specialist shop about Techron - all the ones I've spoke with use it). If you're driving a sportscar, there'll be higher flowing injectors available. Interesting for this discussion as you can then pick up a used set of stockers for cheap, send [i]those[/i] to the shop and not be without your ride for long.

Also: has nobody actually mentioned tire pressure, and, for that matter, tire design? there are tradeoffs here, too. Lacking a pyrometer, just try running your tires a bit over spec'ed pressure. There used to be a rule about pressure increase from cold to hot, but that was for bias tires and likely doesn't apply any more. If you've got a pyrometer, you want a nice even temp increase across the treads. And you want [i]dry[/i] air. Nitrogen is best. Scuba-air is second best (it's been very dried out). Otherwise, ask whoever owns the compressor if it's been drained recently. Try a body shop or garage where they're using pneumatic tools ,as moisture's bad for the tools. (time was, body shops were best because of the care they had to take for the paint guns, but they're not run off the same compressors any more). Look at fuel mileage ratings the next time you're replacing a suit of tires - and remember that you're trading off mileage for something else, but for folks seriously considering some of the driving tactics advocated here, this shouldn't matter much.

Ditto aerodynamics. Air dams are easy to install, do actually work, even sub 65MPH. Get a flexible one so when you hit a curb with it when parking it won't matter.

Oh - and you could just buy a higher mileage car. My wife got one of the first US Priuses. She drives it hard and has been getting 50+ MPG for years now.

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