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Journal: Continuation on education 13

Journal by jd

Ok, I need to expand a bit on my excessively long post on education some time back.

The first thing I am going to clarify is streaming. This is not merely distinction by speed, which is the normal (and therefore wrong) approach. You have to distinguish by the nature of the flows. In practice, this means distinguishing by creativity (since creative people learn differently than uncreative people).

It is also not sufficient to divide by fast/medium/slow. The idea is that differences in mind create turbulence (a very useful thing to have in contexts other than the classroom). For speed, this is easy - normal +/- 0.25 standard deviations for the central band (ie: everyone essentially average), plus two additional bands on either side, making five in total.

Classes should hold around 10 students, so you have lots of different classes for average, fewer for the band's either side, and perhaps only one for the outer bands. This solves a lot of timetabling issues, as classes in the same band are going to be interchangeable as far as subject matter is concerned. (This means you can weave in and out of the creative streams as needed.)

Creativity can be ranked, but not quantified. I'd simply create three pools of students, with the most creative in one pool and the least in a second. It's about the best you can do. The size of the pools? Well, you can't obtain zero gradient, and variations in thinking style can be very useful in the classroom. 50% in the middle group, 25% in each of the outliers.

So you've 15 different streams in total. Assume creativity and speed are normally distributed and that the outermost speed streams contain one class of 10 each. Start with speed for simplicity I'll forgo the calculations and guess that the upper/lower middle bands would then have nine classes of 10 each and that the central band will hold 180 classes of 10.

That means you've 2000 students, of whom the assumption is 1000 are averagely creative, 500 are exceptional and 500 are, well, not really. Ok, because creativity and speed are independent variables, we have to have more classes in the outermost band - in fact, we'd need four of them, which means we have to go to 8000 students.

These students get placed in one of 808 possible classes per subject per year. Yes, 808 distinct classes. Assuming 6 teaching hours per day x 5 days, making 30 available hours, which means you can have no fewer than 27 simultaneous classes per year. That's 513 classrooms in total, fully occupied in every timeslot, and we're looking at just one subject. Assuming 8 subjects per year on average, that goes up to 4104. Rooms need maintenance and you also need spares in case of problems. So, triple it, giving 12312 rooms required. We're now looking at serious real estate, but there are larger schools than that today. This isn't impossible.

The 8000 students is per year, as noted earlier. And since years won't align, you're going to need to go from first year of pre/playschool to final year of an undergraduate degree. That's a whole lotta years. 19 of them, including industrial placement. 152,000 students in total. About a quarter of the total student population in the Greater Manchester area.

The design would be a nightmare with a layout from hell to minimize conflict due to intellectual peers not always being age peers, and neither necessarily being perceptual peers, and yet the layout also has to minimize the distance walked. Due to the lack of wormholes and non-simply-connected topologies, this isn't trivial. A person at one extreme corner of the two dimensional spectrum in one subject might be at the other extreme corner in another. From each class, there will be 15 vectors to the next one.

But you can't minimize per journey. Because there will be multiple interchangeable classes, each of which will produce 15 further vectors, you have to minimize per day, per student. Certain changes impact other vectors, certain vector values will be impossible, and so on. Multivariable systems with permutation constraints. That is hellish optimization, but it is possible.

It might actually be necessary to make the university a full research/teaching university of the sort found a lot in England. There is no possible way such a school could finance itself off fees, but research/development, publishing and other long-term income might help. Ideally, the productivity would pay for the school. The bigger multinationals post profits in excess of 2 billion a year, which is how much this school would cost.

Pumping all the profits into a school in the hope that the 10 uber creative geniuses you produce each year, every year, can produce enough new products and enough new patents to guarantee the system can be sustained... It would be a huge gamble, it would probably fail, but what a wild ride it would be!


Journal: History books can be fun (but usually aren't and this is a Bad Thing) 2

Journal by jd

Most people have read "1066 and all that: a memorable history of England, comprising all the parts you can remember, including 103 good things, 5 bad kings and 2 genuine dates" (one of the longest book titles I have ever encountered) and some may have encountered "The Decline and Fall of Practically Everybody", but these are the exceptions and not the rule. What interesting - but accurateish - takes on history have other Slashdotters encountered?


Journal: HOWTO: Run an educational system 1

Journal by jd

The topic on Woz inspired me to post something about the ideas I've been percolating for some time. These are based on personal teaching experience, teaching experience by siblings and father at University level and by my grandfather at secondary school, 6th form college and military acadamy. (There's been a lot of academics in the family.)

Anyways, I'll break this down into sections. Section 1 deals with the issues of class size and difference in ability. It is simply not possible to teach to any kind of meaningful standard a group of kids of wildly differing ability. Each subject should be streamed, such that people of similar ability are grouped together -- with one and only one exception: you cannot neglect the social aspect of education. Some people function well together, some people dysfunction well together. You really want to maintain the former of those two groups as much as possible, even if that means having a person moved up or down one stream.

Further, not everyone who learns at the same pace learns in the same way. Streams should be segmented according to student perspective, at least to some degree, to maximize the student's ability to fully process what they are learning. A different perspective will almost certainly result in a different stream. Obviously, you want students to be in the perspective that leads them to be in the fastest stream they can be in.

There should be sufficient divisions such that any given stream progresses with the least turbulence possible. Laminar flow is good. There should also be no fewer than one instructor per ten students at a secondary school level. You probably want more instructors in primary education, less at college/university, with 1:10 being the average across all three.

Section 2: What to teach. I argue that the absolute fundamental skills deal in how to learn, how to research, how to find data, how to question, how to evaluate, how to apply reasoning tools such as deduction, inference, lateral thinking, etc, in constructive and useful ways. Without these skills, education is just a bunch of disconnected facts and figures. These skills do not have to be taught directly from day 1, but they do have to be a part of how things are taught and must become second-nature before secondary education starts.

Since neurologists now believe that what is learned alters the wiring of the brain, the flexibility of the brain and the adult size of the brain, it makes sense that the material taught should seek to optimize things a bit. Languages seem to boost mental capacity and the brain's capacity to be fault-tolerant. It would seem to follow that teaching multiple languages of different language families would be a Good Thing in terms of architecturing a good brain. Memorization/rote-learning seems to boost other parts of the brain. It's not clear what balance should be struck, or what other brain-enhancing skills there might be, but some start is better than no start at all.

Section 3: How to test. If it's essential to have exams (which I doubt), the exam should be longer than could be completed by anyone - however good - within the allowed time, with a gradual increase in the difficulty of the questions. Multiple guess choice should be banned. The mean and median score should be 50% and follow a normal distribution. Giving the same test to an expert system given the same level of instruction as the students should result in a failing grade, which I'd put at anything under 20% on this scale. (You are not testing their ability to be a computer. Not in this system.)

Each test should produce two scores - the raw score (showing current ability) and the score after adjusting for the anticipated score based on previous test results (which show the ability to learn and therefore what should have been learned this time - you want the third-order differential and therefore the first three tests cannot be examined this way). The adjusted score should be on the range of -1 (learned nothing new, consider moving across to a different perspective in the same stream) to 0 (learned at expected rate) to +1 (learning too fast for the stream, consider moving up). Students should not be moved downstream on a test result, only ever on a neutral evaluation of some kind.

Section 4: Fundamentals within any given craft, study or profession should be taught as deeply and thoroughly as possible. Those change the least and will apply even as the details they are intertwined with move in and out of fashion. "Concrete" skills should be taught broadly enough that there is never a serious risk of unemployability, but also deeply enough that the skills have serious market value.

Section 5: Absolutely NO homework. It's either going to be rushed, plagarized or paid-for. It's never going to be done well and it serves no useful purpose. Year-long projects are far more sensible as they achieve the repetitious use of a skill that homework tries to do but in a way that is immediately practical and immediately necessary.

Lab work should likewise not demonstrate trivial stuff, but through repetition and variation lead to the memorization of the theory and its association with practical problems of the appropriate class.

Section 6: James Oliver's advice on diet should be followed within reason - and the "within reason" bit has more to do with what food scientists and cookery scientists discover than with any complaints.

Section 7: Go bankrupt. This is where this whole scheme falls over -- to do what I'm proposing seriously would require multiplying the costs of maintaining and running a school by 25-30 with no additional income. If it had a few billion in starting capital and bought stocks in businesses likely to be boosted by a high-intensity K-PhD educational program, it is just possible you could reduce the bleeding to manageable proportions. What you can never do in this system is turn a profit, although all who are taught will make very substantial profits from such a system.

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Journal: I don't know which is scarier

Journal by jd

That I am old enough to remember where my current .sig came from, or that nobody else is.....! For those who are suffering from a memory lapse, here is the sig: "The world is in darkness. To erase data is to suppress truth; to halt computing is to shackle the mind."

Ok, ok, you're too lazy to google it, so here's the link: Son of Hexadecimal Kid

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Journal: Automotive Security

Journal by jd

According to the Center for Automotive Embedded Systems Security, there are serious security flaws in the existing technology. Not necessarily a big deal, for now, as they observe that the risks are low at the current time. Emphasis on "current". They also state that no crackers have been observed to use the required level of sophistication. Again, emphasis needs to be on "observed". Yes, it may well be a while before automotive networks reach the point where this is exploited in the wild (at least to any scale), but I would remind you that it took Microsoft from Windows 3.0 through to Windows XP Service Pack 2 to take security even remotely seriously. That's a long, long time. And Microsoft had nothing like the install-base of the car industry. Further, the qualifications required by most companies to be a system administrator were a good deal steeper than the requirements for a car mechanic, so systems administrators were likely far more familiar with the issues involved. Also, said systems administrators are far more accountable for security issues, since there are plenty of third-party tools that novice users can use to spot malicious software.

The first question is why this even matters. It doesn't affect anyone today. No, but it's guaranteed to affect at least some current Slashdot readers in their lifetime and, depending on how rapidly car networks develop, may affect a significant fraction surprisingly fast. Technology doesn't move at Stone Age speeds any more. Technology advances rapidly and you can't use obsolete notions of progress to determine what will happen next year or over the next decade.

The second question is what anyone could seriously do, even if it was an issue. Not too many Slashdotters own automotive companies. In fact, I doubt if ANY Slashdotters own automotive companies. Well, the validation tools are Open Source. MISRA has a fair few links to members and software packages. In fact, even if developers just developed an understanding of MISRA's C and C++ specifications it might be quite valuable as it would allow people to understand what is being done (if anything) to improve reliability and to understand how (if at all) this impacts security. You don't get reliability for free, there will be some compromises made elsewhere.

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Journal: Has anyone had problems with DB companies? What therapies work with bosses? 4

Journal by jd

I've been having problems with Enterprise DB. This company maintains the Windows port of Postgres, but I have been finding their customer service.... less than satisfactory. This is the second time in, oh, 21 years that I've actually been infuriated by a company. However, to be entirely fair to the business and indeed the sales person, it is entirely possible this was a completely freak incident with no relationship to normal experience. There were all kinds of factors involved, so it's a messy situation all round, but the hard-sell aggressiveness and verbal abuse went way beyond what I have ever experienced from a professional organization in two DECADES. What I want to know from other Slashdotters is whether this is about on-par with the tales of meteorites landing on someone's sofa (which is my personal suspicion) or whether it's a more insidious issue. Please, please, please, do not take one incident as a general rule. I've not seen any article on Slashdot or LWN reporting wider issues with them, which you know perfectly well would have happened had there been a serious, widespread problem. Especially with all of the reporting on database issues over recent times and the search for alternatives to MySQL once leading developers defected and major forks arose.

This is, however, a major question. Like it or not, we need databases we can rely on and trust, which means that when they are backed by companies, we need the companies that back them to be honorable. (PostgreSQL itself isn't owned, so I trust the engine itself just fine. The development team is very impressive - and, yes, I do monitor the mailing lists.) Value-added only has any added value if it's valuable.

What is worse, from my perspective, is that my current boss is now treating it like this is how companies work when reselling Open Source products. His practical experience was being on the receiving end of all this. If we're to take advantage of the freedom (and bloody high quality) provided in the Open Source world, I need to deprogram him of the notion that they give hassle and sell grief. Does anyone have any experience doing this?

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Journal: Save TV for Geeks! 2

Journal by jd

A petition calling for the return of perhaps the most important television show since The Great Egg Race is currently running but isn't exactly getting anywhere fast. It is vitally important that intellectually-stimulating shows be encouraged -- the consequence of failure (24 hours of Jersey Shore on all channels) is too horrible to contemplate. Unfortunately, as things stand, that's exactly what we are heading towards. Save your television and your mind before it's too late!

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Journal: 1-3% of all mainstream stars have planets?

Journal by jd

The venerable BBC is reporting that a survey of light emitted from white dwarfs showed that between 1% and 3% had material (such as silicon) falling into the star on a continuous basis, potential evidence of dead worlds and asteroids. On this basis, the authors of the study speculate that the same percentage of mainstream stars in the active part of their life will have rocky matter. This is not firm evidence of actual planetary formation, as asteroids would produce the same results, but it does give an upper bound and some idea of what a lower bound might be for planetary formation.

Aside from being a useful value for Drake's Equation, the rate of planetary formation would be valuable in understanding how solar systems develop and what sort of preconditions are required for an accretion disk of suitable material to form.

Because the test only looked for elements too heavy to have been formed in the star, we can rule out the observations being that of cometary debris.

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Journal: Fireball, but not XL5 3

Journal by jd

Four fireballs, glowing blue and orange, were visible last night over the skies of the Carolinas on the southeast coast of the United States, followed by the sound of an explosion described as being like thunder. Reports of hearing the noise were coming in from as far afield as Connecticut. There is currently no word from NASA or the USAF as to what it could be, but it seems improbable that anything non-nuclear the military could put up could be heard over that kind of distance. It therefore seems likely to be a very big meteorite.

The next question would be what type of meteorite. This is not an idle question. The one slamming into the Sudan recently was (a) extremely big at an estimated 80 tonnes, and (b) from the extremely rare F-class of asteroid. If this new meteorite is also from an F-class asteroid, then it is likely associated with the one that hit Sudan. This is important as it means we might want to be looking very closely for other fragments yet to hit.

The colours are interesting and allow us to limit what the composition could have been and therefore where it came from. We can deduce this because anything slamming through the atmosphere is basically undergoing a giant version of your basic chemistry "flame test" for substance identification. We simply need to look up what metals produce blue, and in so doing we see that cadmium does produce a blue/violet colour, with copper producing more of a blue/green.

Other metals also produce a blue glow and tables of these colours abound, but some are more likely in meteoric material than others. Cadmium exists in meteorites. Well, all elements do, if you find enough meteorites. but it exists in sufficient quantity that it could produce this sort of effect. (As noted in the chemmaster link, low concentrations can't be detected by this method, however this is going to be vastly worsened by the fact that this isn't a bunsen burner being used and the distance over which you're observing is extreme.)

Ok, what else do we know? The fireballs were also orange. Urelites, such as the Sudan impact, contain a great deal of calcium, which burns brick-red, not orange. This suggests we can rule out the same source, which in turn means we probably don't have to worry about being strafed the way Jupiter was with the Shoemaker-Levy comet (21 impacts).

What can we say about it, though? Well, provided the surviving fragments didn't fall into the ocean, it means every meteorite hunter on the planet will be scouring newspaper stories that might indicate where impacts occurred. Meteoric material is valuable and anything on a scale big enough to be heard across the entire east coast of the US is going to be worth looking for. It had split into four in the upper atmosphere, so you're probably looking at a few thousand fragments reaching ground level that would exceed a year's average pay.

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Journal: What constitutes a good hash anyway? 3

Journal by jd
In light of the NIST complaint that there are so many applicants for their cryptographic hash challenge that a good evaluation cannot be given, I am curious as to whether they have adequately defined the challenge in the first place. If the criteria are too loose, then of course they will get entries that are unsuitable. However, the number of hashes entered do not seem to be significantly more than the number of encryption modes entered in the encryption mode challenge. If this is impossible for them to evaluate well, then maybe that was also, in which case maybe we should take their recommendations over encryption modes with a pinch of salt. If, however, they are confident in the security and performance of their encryption mode selections, what is their real objection in the hashing challenge case?

But another question one must ask is why there are so many applicants for this, when NESSIE (the European version of this challenge) managed just one? Has the mathematics become suddenly easier? Was this challenge better-promoted? (In which case, why did Slashdot only mention it on the day it closed?) Were the Europeans' criteria that much tougher to meet? If so, why did NIST loosen the requirements so much that they were overwhelmed?

These questions, and others, look doomed to not be seriously answered. However, we can take a stab at the criteria and evaluation problem. A strong cryptographic hash must have certain mathematical properties. For example, the distance between any two distinct inputs must be unconnected to the distance between the corresponding outputs. Otherwise, knowing the output for a known input and the output for an unknown input will tell you something about the unknown input, which you don't want. If you have a large enough number of inputs and plot the distance of inputs in relation to the distance in outputs, you should get a completely random scatter-plot. Also, if you take a large enough number of inputs at fixed intervals, the distance between the corresponding outputs should be a uniform distribution. Since you can't reasonably test 2^512 inputs, you can only apply statistical tests on a reasonable subset and see if the probability that you have the expected patterns is within your desired limits. These two tests can be done automatically. Any hash that exhibits a skew that could expose information can then be rejected equally automatically.

This is a trivial example. There will be other tests that can also be applied automatically that can weed out the more obviously flawed hashing algorithms. But this raises an important question. If you can filter out the more problematic entries automatically, why does NIST have a problem with the number of entries per-se? They might legitimately have a problem with the number of GOOD entries, but even then all they need to do is have multiple levels of acceptance and an additional round or two. eg: At the end of human analysis round 2, NIST might qualify all hashes that are successful at that level as "sensitive-grade" with respect to FIPS compliance, so that people can actually start using them, then have a round 3 which produces a pool of 3-4 hashes that are "classified-grade" and a final round to produce the "definitive SHA-3". By adding more rounds, it takes longer, but by producing lower-grade certifications, the extra time needed to perform a thorough cryptanalysis isn't going to impede those who actually use such functions.

(Yes, it means vendors will need to support more functions. Cry me a river. At the current scale of ICs, you can put one hell of a lot of hash functions onto one chip, and have one hell of a lot of instances of each. Software implementations are just as flexible, with many libraries supporting a huge range. Yes, validating will be more expensive, but it won't take any longer if the implementations are orthogonal, as they won't interact. If you can prove that, then one function or a hundred will take about the same time to validate to accepted standards. If the implementations are correctly designed and documented, then proving the design against the theory and then the implementation against the design should be relatively cheap. It's crappy programming styles that make validation expensive, and if you make crappy programming too expensive for commercial vendors, I can't see there being any problems for anyone other than cheap-minded PHBs - and they deserve to have problems.)

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Journal: Beowulf MMORGs 3

Journal by jd

Found this interesting site, which is focussing on developing grid computing systems for gaming. The software they seem to be using is a mix of closed and open source.

This could be an important break for Linux, as most of the open source software being written is Linux compatible, and gaming has been the biggest problem area. The ability to play very high-end games - MMORGs, distributed simulators, wide-area FPS, and so on, could transform Linux in the gaming market from being seen as a throwback to the 1980s (as unfair as that is) to being considered world-class.

(Windows machines don't play nearly so nicely with grid computing, so it follows that it will take longer for Microsoft and Microsoft-allied vendors to catch up to the potential. That is time Linux enthusiasts can use to get a head-start and to set the pace.)

The question that interests me is - will they? Will Linux coders use this opportunity of big University research teams and big vendor interest to leapfrog the existing markets completely and go straight for the market after? Or will this be seen as not worth the time, the same way that a lot of potentially exciting projects have petered out (eg: Open Library, Berlin/Fresco, KGI, OpenMOSIX)?

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Journal: The Lost Tapes of Delia Derbyshire

Journal by jd
Two hundred and sixty seven tapes of previously unheard electronic music by Delia Derbyshire have been found and are being cataloged.

For those unfamiliar with Delia Derbyshire, she was one of the top pioneers of electronic music in the 1950s and 1960s. One of her best-known pieces was the original theme tune to Doctor Who. According to Wikipedia, "much of the Doctor Who theme was constructed by recording the individual notes from electronic sources one by one onto magnetic tape, cutting the tape with a razor blade to get individual notes on little pieces of tape a few centimetres long and sticking all the pieces of tape back together one by one to make up the tune".

Included in the finds was a piece of dance music recorded in the mid 60s, examined by contemporary artists, revealed that it would be considered better-quality mainstream today. Another piece was incidental music for a production of Hamlet.

The majority of her music mixed wholly electronic sounds, from a sophisticated set of tone generators and modulators, and electronically-altered natural sounds, such as could be made from gourds, lampshades and voices.

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Journal: Well, this is irritating. 3

Journal by jd
Someone has trawled through YouTube and flagged not only the episodes of The Tripods, but also all fan productions, fan cine footage and fan photography of the series. How so, can't you buy it on DVD? Only the first season, the second exists only in pirated form at scifi conventions, and of course the fan material doesn't exist elsewhere at all. The third season, of course, was never made, as the BBC had a frothing xenophobic hatred of science fiction at the time. (So why they made a dalek their general director at about that time, I will never know...)

What makes this exceptionally annoying is that the vast bulk of British scifi has been destroyed by the companies that produced it, the vast bulk of the remainder has never seen the light of day since broadcast, and the vast bulk of what has been released has been either tampered with or damaged in some other way, often (it turns out later) very deliberately, sometimes (again it turns out later) for the purpose of distressing the potential audience.

I've nothing against companies enforcing their rights, but when those companies are acting in a cruel and vindictive fashion towards the audience (such as John Nathan Turner's FUD of audiences being too stupid to know what they like, or too braindead to remember what they have liked), and the audiences vote with their feet, on what possible grounds can it be considered justified for those companies to (a) chain the audience to the ground, and (b) then use the immobility of the audience to rationalize and excuse the abuse by claiming the audience isn't going anywhere?

I put it to the Slashdot Court of Human/Cyborg Rights that scifi fans are entitled to a better, saner, civilized explanation, and that whilst two wrongs can never make a right, one wrong is never better.

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Journal: 1nm transistors on graphene

Journal by jd
Well, it now appears the University of Manchester in England has built 1nm transistors on graphene. The article is short on details, but it appears to be a ring of carbon atoms surrounding a quantum dot, where the quantum dot is not used for quantum computing or quantum states but rather for regulating the electrical properties. This is still a long way from building a practical IC using graphene. It is, however, a critical step forward. The article mentions other bizare behaviours of graphene but does not go into much detail. This is the smallest transistor produced to date.

A LISP programmer knows the value of everything, but the cost of nothing. -- Alan Perlis