Catch up on stories from the past week (and beyond) at the Slashdot story archive

 



Forgot your password?
typodupeerror
×

Comment Re:Units! (Score 1) 159

If we are into nitpicking, Volt (singular!) is a unit of electric potential (energy/charge); Joule (Volt*Coulomb = Newton*Meter = ...) is a unit of (potential and all other forms of) energy.

Comment price is what you pay, value is what you get. (Score 1) 643

> one fat finger led to the temporary destruction of nearly 1 trillion dollars of value!

And explosion in a power plant destroys value, a drop in the stock price of the power company doesn't: all the plants, factories and offices you might have aquired a share of are still there and just as well as they have been yesterday. Why is it that people begin to like their stock or even the houses the live in less just because of a different price tag? The dividend doesn't depend on the quotation and the house will still be as big as it has been yesterday, so why should you care what others are currently willing to pay for it? - That is, unless you are trying to make a living as a gambler or hustler for sucker bets (aka trader), in which case you simply made an error of judgement by not correctly considering the fat finger factor when placing your bets and have only yourself to blame.

Comment Re:About emissions displacement (Score 1) 161

I might also add that Austria gets almost 2/3 of its electricity by hydropower. If you recharge your car overnight, i.e. well outside peak hours, it's practically zero emmision.

The point you brought up is true also e.g. all Austrian coil plants have desulphurization (and even sell the generated gypsum) and the gas plants are usually located in or near the city to provide community heating instead of waste heat. Neither would be possible with small decentralized units.

Comment Decoys anyone? (Score 1) 252

Strange that nobody has mentioned it yet, but I guess it's a good bet that there will be hundreds of red balloons rising on Dec 5. Besides the obvious "because we can" motive, if you are after the prize money, it makes sense to launch a few decoys the location of which is only known to yourself. Even a few of those and the contest is no longer about spotting the balloons, but about picking the correct 10 out of the confirmed sightings.

It would have made a lot more sense to launch the balloons before announcing the challenge.

Comment Re:Please don't. (Score 1) 300

You have it the wrong way around. The only job of those "morons" was and is to provide a pseudo-scientific fig leaf to the decision makers - this is their only purpose. Economics provides a huge repository of established (and often contradictory) theories to choose from and is fuzzy enough, so that the choice of parameters, input data and model relations provide more than enough wiggle room to make a model for any desired outcome while avoiding any "gross negligence" a judge could pinpoint. And it's a job they did very well indeed, as you would think that after having destroyed trillions of wealth form customers and third parties, many Wallstreet executives would be in jail now rather than paying themselves bonuses from the bailout money they received.

Comment Goodhart's law (Score 1) 300

This cannot possibly work because "any observed statistical regularity will tend to collapse once pressure is placed upon it for control purposes" and Danielsson's corollary "A risk model breaks down when used for regulatory purposes".

The very moment any model - regardless how cleverly designed - is published and started to be used to make money on a significant scale, peolple will start gaming the system. This will necessarily destroy any information carrying correlation. Why? Because, as it is impossible to generally directly predict economic success except after the fact any more than it is possible generally to predict whether a given program will halt or not w/o running it, you have to use proxies. These proxies are always easier to manipulate on purpose than they are by influencing them as a side effect to a different purpose.

A good example is the number of papers published as a measure for scientific excellence and predictor of future academic success. A good indicator - but only as long a nobody counts them and uses it to direct money flows. The moment you do that, researches will see publication as an end in itself, and not as a byproduct of successful research and the measure will lose most of its predictive power.

In economics, it's even worse, as money made on speculation spends exactly the same as money earned by building value: Charts of stock prices would be an excellent predictor as market prices in theory should aggregate all available information - but only as long nobody uses them to estimate value or predict future prices. With chart analysis used by many market actors and companies being allowed to manipulate their own stock price (vie buy-backs, option programs, etc.) you get so many artificial feedback effects into the system that they dominate the system's dynamics and the actual signal gets lost in the noise.

Comment What is a reasonable time-frame? (Score 1) 203

A 5 to 10 year time frame seems quite reasonable for a project like this - if anything it's a bit on the tight side; technological revolutions in other industries like manufactoring usually take considerably longer. This is not about migrating a couple of office destops and a server or two - this is about migrating the complete IT infratructure of Germany's third largest city and affects pretty much every piece of software that is currently used in the public sector. Already the interal and external interoperabilty issues (with other administrative bodies, contractors and the public) pose a formidable challenge. And you have to do it as an early adopter in the worst possible environment for change - after all, this is not a "dictatoric" private company but a city government with politics, hidden agendas, entreched formal and (even harder to identify as well to change) informal work flows and bureaucratic procedures, subborn tenured civil servents and legal issues behind every corner. It's in many way's the worst case scenario for Linux migration, a really Herculian task! If you can make it there, then anywhere else will seem trivial by comparison.

Comment This might actually be a good idea IF ... (Score 1) 161

... you do the flight unmanned, don't mind several decades in transit and are able to mothball the station in a way that you can reliably unfreeze and reactivate it after many years in space. That way, you might be able to use low thrust, low energy, solar or nuclear powered high specific impulse ion or plasma drives to haul the station there.

A pioneer mission can then try to reactivate the station and if successful, you already have habitat, life support and scientific equipment in place for subsequent missions. This would be especially useful if fuel production in situ is planned (as with the "Mars Direct" mission plans) so the station can be at least partly resupplied there.

ignatius

Comment Rule of Thumb (Score 1) 550

> The US wasn't the aggressor in the Korean or Vietnam Wars

There are exceptions, but generally, in my book, unless having been directly attacked first, whoever is fighting farther away from home is the aggressor by default.

ignatius

Comment Makes Sense (Score 1) 550

Make perfect sense from the US POV: No other country has more space assets to lose and less foreign space targets to shoot down than the US. Also, no other military is more dependent on an operational space infrastructure to wage war. And of course: reconnaissance favors the attacker - and the US has been the agressor in all military conflicts since Pearl Harbour.

If Obama gets away with this proposal, it would be a major strategic coup - if Russia, China, etc. are stupid enough to fall for the trap (the EU probably is). Otherwise it still makes for a good diplomacy stunt.

Slashdot Top Deals

Systems programmers are the high priests of a low cult. -- R.S. Barton

Working...