Archive for August, 2009

Health Care and the UK's NHS

August 28, 2009

A friend of mine in the UK just emailed me. Here’s a snippet of what he had to say:

I am currently listening to news coverage of the debate taking place over there in the US about health care. There are some politicians citing the National Health Service as being an insidious service which rations out health care. I could not believe my ears when I heard the arguments against the NHS. How much insurance cover would I have needed in the US for the following treatments:- a partial laminectomy, the removal of the gall bladder, treatment(35 shots of radiotherapy) for prostate cancer, three months of Chemotherapy prior to the removal of the bladder and prostate,the resultant hospital treatment, all together about four weeks including five days on Intensive Care wards, and continued monitoring in the way of CAT and MRI scans and X-rays and not to mention numerous back-up consultations, and, most recently, consultations prior to my lung biopsy, during which fluid was drawn from the lung for analysis, the biopsy and resultant treatment including 48 hours on a High Dependency Unit, and, finally admission and treatment, including another CAT scan,for the blood clot in the lung. Oh, and don’t forget all the drugs I have been on over the years, and am still on. Total cost to yours truly, not a penny!! I think I know which system I prefer!

None of the arguments so far put forward agains health care reform ring true, except those that inadvertantly admit to being self-serving. They are either scare stories, that is to say, lies, or they are grounded in something other than a concern about health care. For example, those who say they oppose it on cost grounds are the same ones who voted for enough spending to change a budget surplus into a record level deficit. Those who oppose it on the basis that government can’t do things well are the same ones who fight to retain Medicare (but are careful to ensure that Medicare can’t use its full bargaining power). The only truth-sayers are those who fear that it would hurt the insurance industry (which is making big campaign contributions) and those who are opposing it because it’s the Democrats and Obama who are pushing for it.

And of course, that’s the point. The goal of the opposition is to defeat Obama and the Democrats. Health care is just a tool. When you hear the arguments, remember that. And think of my poor, downtrodden British friend.

First Quarter Moon

August 26, 2009

Tonight is a first quarter, or waxing moon. As seen from Earth, it’s a half moon, and thereby hangs a tale.

When you look at a half moon, one that looks like this:  D  , you are looking at the sunrise line, or terminator. Yes, you can see the terminator if you look at a crescent moon, or a gibbous moon, but it’s only when you are directly over the sunrise line that you see that kind of a half moon. When you look at the moon at your local sunset (about 19:00 PDT in the Summer) you are standing on the sunset line of the Earth, also called the terminator. If you think about it,  the only way this can happen is if the moon is directly behind the Earth in its orbit around the Sun. Go do a drawing. you have the moon and the Earth in line, like this:  o  O –>  with the arrow indicating the movement of the Earth in its orbit. To complete the picture, the Sun would be off the top of the page, and the bottom half of those circles would be dark.

Now, the Earth travels about 29.6km/sec in its orbit around the sun. And the moon, on average, is 382,500 from the Earth. (Bear with me here, the math is almost over).  So, the Earth covers the Earth-Moon distance in about 3.5hours.

That means that when you look at a First Quarter Moon, at sunset, you are looking at the very spot in space that the Earth was at, 3.5 hours ago. In the morning, should you be up early enough to see a Last Quarter Moon at local sunrise, you will be looking at the very spot in space where the Earth will be about the time you sit down for your pre-luncheon snack.

Go out tomorrow evening and try it.

Updated to make timeless.

Wednesday Wii — A Balanced View

August 12, 2009

The Wii Fit has an interesting approach to improving and measuring your balance. It’s a two stage process. First, you train, on various exercises and minigames, doing things that improve your balance. In the artificial neural net side of Systems Science, we call this the ‘training set’, and if you think about it, the Wii Fit is training a real neural net, the three pounds of jellied neurons you carry at the top of your spinal column. The yoga exercises improve your static balance — the ‘Tree’ and ‘Half Moon’ poses, for example. Dynamic balance is through the strength exercises (‘Single Leg Lift’), or through true games (‘Penguin Slide’). Once you have trained up, you are then tested, but not on the things you trained on, instead, you have a ‘test set’, of exercises that are mostly unlike any of the games. Examples are the ‘Basic Balance’ test, and the measurement made whenever you run a body test. This is a good approach, I use something like it to train artificial neural nets, but the Wii Fit implementation leaves something to be desired. There’re two problems that I have encountered so far, response time, and lack of a trainable baseline.

The response time is a minor problem because it is only noticeable in a couple of the games — the ‘tightrope walk’ between two buildings, and the ‘walk your bubble’ down the stream games. In the other games, the character on screen responds more or less instantly to your weight shifts on the balance board. In those two, there is a noticeable delay, probably programmer-induced, between movement and action on the screen. The problem with this is that it’s teaching you the wrong thing. It’s teaching you, the system, to respond to what you think your body’s going to do, not to what it’s actually doing. This is a good idea for a pilot — you want to stay ahead of the aircraft — but not for inculcating basic balance skills.

The second problem is even worse, since it pervades all of the games and exercises. When you train on the Wii, you never get to evaluate your balance against an absolute measure, it’s always against where you were when the exercise started. You do get to see your absolute balance in a number of places, but nowhere that it does you any good. For example, every time you move to a new game, there’s a brief period where a green fuzzball moves around on the screen. That shows where your balance is, using the balance board as an absolute frame of reference. However, the display only lasts a second or so, and you don’t have a chance to get into a truly balanced position to see what it feels like. You also get to see your absolute balance during the initial phase of the body test, and during the ‘Basic Balance’ test, one of the tests that the Wii has selected just for you. In the first case, it’s only for a few seconds. It’s longer in the second test, but you have no control over when you are given that test, it appears at the whim of the Wii gods, and you can’t rerun it.

All the training exercises measure relative balance — relative to how you were standing when the exercise started. They have these little yellow circles, and your little red balance point moves around as you shift your balance, that little red dot starts in the centre every time. You can see this best in the basic breathing exercise, or in the Half Moon. No matter how far over you are leaning, your red dot comes up in the centre of the yellow, every time. Try it. Start the breathing exercise, and make sure all your weight is on one foot. See? Not only does this not give you as much useful information as it might, it can throw you off if it takes you longer to settle into a position than the Wii thinks you should. A brief wobble at the wrong moment will make the Wii think you are leaning well away from where you should be.

While the underlying approach is good — you don’t want people training to the test — the implementation is frustratingly flawed. It’s like training a ANN to find the global maximum, but lopping off the top ten percent of the fitness function. What Nintendo should do is have one exercise, Basic Breathing is my suggestion, that lets you stand on the balance board and see how far off centre your actual balance is.

Hello, WordPress

August 10, 2009

Just moved here from LiveJournal. Importing all my previous posts and adding categories for them took about half an hour. Your mileage may vary. WP offers options, friendlier interface, although I do miss the cutesy ‘Mood’ and ‘Music’ options.

The Falafel Bullwhip

August 9, 2009

My friend, Kurt, who blogs here at WordPress in his Zephyr 98, has a cute essay on a sandwich. In it, the store where he shops had a shortage of falafel, and so couldn’t make his favorite sandwich. This went on for weeks. Then, suddenly, they had falafel again — tons and tons of falafel. The resulting sandwich was…mmm…Rubenesque, bordering on Dionysian. But the curvacious sandwich isn’t what we are on about in this essay. It’s the falafel, and the oversupply thereof.

You see, Kurt’s sandwich shop appears to be the victim of a common phenomenon in the supply chain world, known as ‘the bullwhip effect’. When a multi-stage supply system has delays built into it, then pent up demand can result in a sudden oversupply, and your inventory flails around like a bullwhip. The best example is in the ‘Beer Game’ AKA the ‘Beer Distribution Game’, for those who don’t want their motives misunderstood. Here’s the wiki on it:

and there’s resources that will let you play online. Go ahead. Play it. I’ll wait.

If you check my Summer Reading entry of a month ago, you will find Peter Senge’s book The Fifth Discipline (1990). He made the Beer Game popular, and tied it to Systems Dynamics. One of the interesting findings he made, from years of using the game, is that the bullwhip effect can occur even when you know what’s going on and try to fight it.

I strongly reccomend the book, Kurt’s blog, and fat falafel sandwiches.

Time Marches On

August 3, 2009

Working in a technical field I am still amazed at how fast technology is progressing. I am not particularly gadget happy, so I don’t need the latest, and I never buy cutting edge. That means I tend to hang on to gear for at least one more product cycle than the rest of the world does. And that means I am always surprised at how the rest of the world has moved on — there’s knowing something intellectually because you read about it, and there’s knowing something because you find you can or cannot do something.

For example, I bought my old home PC eight years ago. It was a mid-range Dell, 800MHz PIII, with a 20GB HDD, running Windows NT. I bought my wife’s old PC a month later, and it was a 900MHz PIII with a 76GB HDD. We both upgraded a couple of years ago — me to Ubuntu, and her to a MacBook. The two PCs were kept for those things that absolutely required Windows. Recently they both started feeling poorley — a keybounce on the power button rendered mine unbootable — so we replaced them with refurbished Optiplexes from Amazon. It’s surprising how good a deal one can get on a used machine.

The point of this story (finally) is that I planned to use one of the old PCs as the start of a home media system. After all, that’s what everyone talks about, right? Repurposing an old PC by installing Ubuntu and a TV card. How hard can it be? So I went on the web to find what the latest was. Hauppage still dominates the field, but there’s a problem. It seems that there’s not a lot of choices out there for PCI cards, and all the software wants 1GB of RAM or more. Well, our two systems started out with 256MB each, and combining them still gave us only half of what was needed, plus, even the “high end” one is underpowered. So, I guess I’ll start slow and build something for our CDs and see where it goes from there. Meanwhile, anybody need a 0.8GHz machine with no memory and a bad hard drive? One that hasn’t been dusted for eight years?

Summer Reading.

August 2, 2009

Edited my July 8 entry to add Clifford Stoll’s “The Cuckoo’s Egg: Tracking a Spy Through the Maze of Computer Espionage”