^zhurnal v.0.36

Howdy, pilgrim! You're in volume 0.36 of the ^zhurnal --- musings on mind, method, metaphor, and matters miscellaneous ... a rather cluttered set of sporadic Good Mistakes. What's it all about? Maybe "... to create moments of philosophy --- that is, to pass from opinion to thought ...." It's also the journal of ^z = Mark Zimmermann. See the ZhurnalyWiki on zhurnaly.com for a parallel "live" Wiki experiment. For back issues of the ^zhurnal see Volumes 0.01, 0.02, ... 0.40, 0.41, ... Current Volume. Send comments & suggestions to "z (at) his (dot) com". Thank you! (Copyright © 1999-2004 by Mark Zimmermann.)

In Search of the Fulcrum

Feynman + Holocaust = In Search of the Fulcrum by Zdzislaw Alexander Melzak. The author is a scholar, a mathematician, a brilliant analytic thinker, a retired professor, a Canadian. He's also a Jew born in Poland, who as a teenager survived the Nazi death camps.

This is an important book. It's also frustrating --- like listening to a slighty dotty genius grand-uncle who can't help but interrupt himself as he alternately reminisces and rants. Melzak dissects the events of his life. He places his own mental processes under a microscope, in much the same fashion as celebrity physicist Richard P. Feynman sometimes did. He remembers. He questions.

Melzak is by turns poetic and crude, objective and intimate. In Search of the Fulcrum is told from a zeroth-person viewpoint --- deeper and more introspective than even a confessional autobiography. Following the mathematical principle of inversion, Melzak turns his own experiences inside-out in his quest for meaning. On occasion he glimpses the goal.

Perhaps Fulcrum most desperately needs an editor. Maybe the project would have worked better as a hypertext, a nonlinear graph with heavy cross-linkage among its nodes. (Wiki?!) It certainly could use an index. A road-map would help too.

But then again, it may be that Fulcrum is best simply as it is: a messy complex stewpot of memories and hypotheses, jokes and guesses, gaps and glimmers --- like life. I bought it by mail, sans review or description, without even a peek at the cover, based only on its author's name and my respect for his mathematical books. Fulcrum was released late and appears to be self-published, though professionally printed and bound. My copy bears the subtitle "Part I: Accounts of Time Lost". The introduction comments, "... volumes 2 and 3 of this book will not be published in my lifetime, volume 1 may be." Thankfully, it has been. I've only begun to read it.

Z. A. Melzak is an extraordinary human being. His spirit is summarized by an epitaph that he wrote for himself:

"He had little to be proud of except perhaps for this: that he differed in almost everything that matters from almost everybody. This sustained him in his struggles by inspiring the belief that he could not be everywhere wrong. He was profoundly grateful not for a glimpse of horror that was vouchsafed him, but for the accident of strength to bear it and to rebuild himself several times upon new foundations."

I must read, and think, more.

(see also Applied Bypasses (14 Apr 1999), Kenning Construction Kit (17 Nov 1999), Creative Devices (1 Jan 2001), ... )

- Friday, March 19, 2004 at 06:02:56 (EST)

Rebellious Hair

"Lather, rinse, repeat", the bottle of shampoo directs. How many literal-minded computer programmers have complained about that infinite loop?

I haven't had a haircut for a couple of decades; my hair falls out as fast as it grows in. (Exception: I trim my moustache every few weeks, to keep it out of harm's way when I eat.) Before that Paulette used to snip off stray strands. Earlier still I cut my own locks with scissors, as I sat perched on the edge of the washbasin and tried to look at the back of my head, using a hand-held mirror to reflect the image from the looking-glass above the sink. Pre-1974 I was clean-shaven, crew-cut, and had actually witnessed the inside of a barber shop. Nowadays I comb my beard with my fingers. It saves time.

I bought a bottle of conditioner recently for another member of the family, and was amused to see it labeled as being for "rebellious hair". Hey, my mane isn't trying to foment revolution --- it's already achieved anarchy!

(see http://www.his.com/~z/zStudentIDs.html as well as Seven Manes (9 Feb 2001), Philadelphia Inquirer (22 Sep 2002), Envelope Pushing (24 Apr 2003), ... )

- Thursday, March 18, 2004 at 05:54:01 (EST)

Reflective Students

Professor Maynard Mack, Jr., aka "Sandy" Mack, directs the Honors Program at the University of Maryland, College Park. A few gems from his conversation yesterday with parents of prospective UM students:

And of course, being a "reflective student" applies not just to classwork, but to all of life ...

A search for other examples of Sandy Mackisms led me to David Bindel, a student of mathematics and computer science now in grad school at Berkeley. His collection of "Sandy's Sermons" [1] from the 1997-99 era provides much to ponder. Bindel himself seems to be a kindred spirit: his "Personal Page" [2] offers many pointers to topics that I already enjoy, plus links to things that I clearly need to learn more about.

Time for me to start studying (and thinking about what I'm studying (and thinking about the act of thinking about what I'm studying, and ... ) ... ) ...

(see also Do Meta (8 May 1999), Meta Hominidae (7 February 2000), Idiocy Amelioration (18 Apr 2000), Meta Man (14 Nov 2001), My Affectations (19 Jan 2003), ... )

- Wednesday, March 17, 2004 at 06:07:55 (EST)

Three New Loop Runs

Jogging around a big circuit, especially through the woods or along a creek, is a magical-marvelous thing (see Loop Course). This past week good fortune takes me around three novel orbits --- thanks to fine weather, fair health, and the foolish hope of getting semi-ready for an ultramarathon some day. Brief notes on the experiences follow (adapted from my posts to Brian Tresp's running blog [1]) ...

Rock Creek Trail + NIH + Georgetown Branch

(Wednesday 10 March 2004) Wonderful run --- if they all felt this great I'd never fret before a marathon again! --- 11+ miles in 123 minutes with no walk breaks, strong legs, cool weather, and "The First Cut Is the Deepest" playing on the mental 8-track tape loop. The afternoon is crisp and breezy. I jog from home into Walter Reed Annex (taking an extra circuit around the mermaid fountain to salute the pulchritude of the sculpture) and through the woods to Rock Creek Trail, then proceed to Cedar Lane, which I take past Stone Ridge School and the National Institutes of Health to Old Georgetown Road. Southward thence, following Arlington Blvd. to Bethesda Ave. to the water fountain near milepost 3.5 of the Capital Crescent Trail. Quick drink, and it’s homeward bound via the usual Georgetown Branch route.

Mea culpa: my qi is disturbed twice by uncharitable thoughts. First, at Beach Drive & Cedar Lane, a mini-truckie-thing swerves around a car stopped for the red light, passes it on the right (!) and almost hits me as it runs straight through the signal. Forgive me, Lyman --- I shook my finger at the driver, a young lady intent on her speeding. (If anybody needs a witness concerning other incidents involving a vehicle with Maryland license plate 1A2730 please ask, and I'll be happy to testify as to what I observed.) Later, along the Georgetown Branch I feel sorrow at the ancient trees which have been chain-sawed to death. Pieces of their trunks lie fresh-hewn next to the trail; they appear to have been felled to improve the southern exposure for some swanky back yard lawns. I momentarily fantasize that the Inner Purple Line trolley is built and toots its whistle at all hours of the day and night, the way the Metropolitan Branch of the B&O does near my home. But no, I shouldn’t wish that upon a wealthy neighborhood, should I? (^_^)

Coming back to my senses: what a superb trek! My measured mile times are 10:37 (Rock Creek 3-4) early in the jaunt and then near the end 10:10 + 9:29 (!) + 10:55 (Georgetown Branch 3.5-0.5), including pauses to cross some major roads. I carry no food, phone, money, water, ID, or GPS. Maybe it’s the feeling of freedom (or foolishness) that makes the jaunt so much fun ...

Sligo Creek + Northwest Branch

(Friday 12 March) Sad news from the doctor today: my 18-month reprieve is over --- it’s back onto the hypertension meds for ^z --- wonder if ACE inhibitors will disqualify me from the Olympics? (^_^) Or perhaps I just have to avoid playing draw poker?

But good news: after the unhappy doctor's app't., a fun run on a new route: ~9 miles (~101 minutes) beginning at the Rec Center on Sligo Creek Parkway just north of Dennis Ave. ... upstream along the banks of bounteous Sligo to Wheaton Regional Park ... then down Northwest Branch, on a real trail (albeit a relatively tame one) with mud, boulders, fallen trees, gulleys, hills, puddles, and great woodsy scenery ... and, at the turnoff to Lockwood Drive (just short of Colesville Road) I vector back to Dennis and follow the streets to my starting point.

I take a wrong turn, as I usually do, on the winding paths in Wheaton Regional --- but fortunately a cute young pony-tailed runner coming the other way is kind enough to set me straight. I follow her along the horse path for a mile until she slows, then pass by and swing onto the Northwest Branch trail across Kemp Mill Road. Four deer take flight at my fearsome approach; they flash their white tails as they bound across a ridge. Signs announce the Rachel Carson Greenway Celebration on Saturday 20 March "...to re-name and extend the Northwest Branch Trail ..." eventually to the Patuxent River --- see http://montgomerytrails.org for more news.

The miles go great along the rocky streamside ... maybe my fantasies to do the 50km HAT Run at the end of the month, or the JFK 50 miler in November, aren't as far-fetched as I have feared ...

Rock Creek Park + Capital Crescent

(Sunday 14 March) ~23.5 comfortable miles this morning, with a little help from my friends ... commencing at the end of my driveway, ~3 miles to the edge of DC via neighborhood streets, the Georgetown Branch, and Rock Creek Trail ... then another ~9 miles along Beach Drive in Rock Creek Park to reach Thompson’s Boat Center on the Potomac near the Kennedy Center ... a jog west along the Georgetown waterfront, and then back home ~10 miles along the Capital Crescent Trail. The GPS "odometer" claims 22.5 miles, but my splits during measured miles between painted markers ("P-P") and official mileposts suggests that the GPS figure is, as usual ~4% low.

The encouragement of compatriots makes the day go nicely: Comrade Evan jogs north from the river, meets me at the National Zoo, and keeps me going at a brisk pace for miles ~9-14 ... Comrade Ken proceeds south from Bethesda and accompanies me for miles ~18-20 ... and a fortuitous encounter with MCRRC's Craig Roodenburg at mile ~22 gives another welcome boost to the home stretch. Thanks, dudes!

Avian sights along the way include a sprinkle of ducks paddling about on Rock Creek, a cluster of geese foraging on a government-owned lawn near the CCT's mile 6.5, and several pairs of scarlet cardinals flitting back and forth across the path in front of me. There are also uncounted baby-carriages, inline-skaters, cyclists, and occasional pods of Galloway-method trainees walking and running together. (Near Virginia Avenue on a grassy hillside a boy and girl in sweatclothes practice prone-supine mouth-to-mouth resuscitation on one another, possibly with humorous as well as amorous intent; they jump to their feet and wish Evan and me "Good morning!" before jogging off after their colleagues.)

My average pace for the ~4.5 hour journey is ~11:40 minutes/mile, with a least-squares-fit deceleration of ~3 seconds/mile/mile. Weather is near-perfect, cool and partly cloudy, and except for the lack of functional water fountains in Rock Creek Park all is splendid. I eat two Clif Bars along the way and feel good at the end. (Now, will I get into the HAT Run, or is it sold out?)

(see also Rock Creek Trail (31 May 2002), Anacostia Tributaries (28 Jan 2003), Capital Crescent Coordinates (5 May 2003), Loop Course (24 Aug 2003), Gps Jogs (9 Mar 2004), ...)

- Tuesday, March 16, 2004 at 09:01:59 (EST)

Simultaneous Chess Matches

Nicholas D. Kristof (in his New York Times op-ed column of 13 Mar 2003) conjures up a wondrously apt simile:
Governing the U.S. is like playing 200 simultaneous chess matches (while whiny columnists second-guess every move on every board). The terrorism chessboard is among the most important, but if we could just devote a bit more energy to the others, we could save thousands of lives ...

This metaphor resonates particularly well if you've ever seen a chess simul, where a grandmaster walks around a circuit from board to board, takes a few seconds to glance at each position, makes a move, and then strolls on to deal with the next opponent. (After ~40 orbits the GM usually has won almost all of the games.)

Kristof's big point --- an excellent one --- is that the world is complex and that it's unwise to focus narrowly on single issues. He observes that the death toll from car accidents in the USA is ~43k/year (= ~120/day) ... from influenza and associated pneumonia, ~36k/year ... from guns, ~26k/year ... and from food-borne illness, ~5k/year.

But statistics, sprinkled as spice onto an article, are like a red flag waved in my face. A quick check in the Statistical Abstract of the United States (2003 edition) reveals that of the annual ~2.4 million deaths in this country more than 900k are due to major cardiovascular disease and another 500k are from cancers. Accidents take 100k (of which motor vehicles account for ~40k, as Kristof correctly states). Diabetes kills ~70k, suicide ~30k, and homicide ~20k. The 'flu and pneumonia account for ~60k (much more than Kristof said).

Many of these deaths are essentially unavoidable, at least in the plausible near future. Others could be prevented at huge expense on a national level but at a trivial cost (or even with significant cash savings!) on a personal basis --- such as the constellation of diseases associated with obesity and lack of exercise, or the automobile-related deaths that follow from drunk driving or excessive speed.

So Mr. Kristof could have made an even stronger case than he did for broadening the government's perspective beyond a single chess board in a simultaneous exhibition. Statistics are good --- not to tell lies with, but to sharpen the understanding of complicated situations.

(see also Racial Relationships (10 Jan 2004), Gambling Addiction (5 Feb 2004), Bad Arithmetic (24 Feb 2004), ... )
- Monday, March 15, 2004 at 06:34:49 (EST)

Big Secret of Prosperity

Why do some societies thrive while others collapse into meltdown mode? Look around the world and you'll see happy, successful communities, even in relatively poor regions --- and you'll also see violently self-destructive subcultures, even in the wealthiest of nations.

The Big Secret is so hugely obvious that, like air, we tend to overlook it: the vast majority of people simply have to voluntarily go about their daily lives peacefully. That's it.

If most folks, most of the time, can rely on their neighbors not to harrass them ... if most folks pretty much mind their own business, but are willing to lend one another a hand in time of need ... if most folks mostly stay out of trouble (and if the rules defining "trouble" are clear and consistent) --- well then, the rest of life tends to handle itself. On the other hand, if a significant fraction of the individuals in an area decide to make a living out of predatory behavior, hurting other people for "fun", taking stuff that isn't theirs (including, on an international scale, invading and exploiting other countries) ... well then, in rather short order life is going to get nasty for everybody. Either the hoodlums will run riot, or the anti-hoodlums will have to spend a big fraction of their resources keeping the scorpions bottled up.

"Anything that's peaceful!" was a slogan of Leonard Read (1898-1983), a quiet and thoughtful student of liberty. The rôle of government, Read suggested, was simply to keep the peace ...

(see also Education Versus Eduction (30 Apr 1999), Anti Learning (30 Jun 2000), Education Of The Youth (1 Dec 2001), Invest In Peace (9 Jul 2002), Century Hence (1 Sep 2002), Personal Positivism (16 Nov 2002), ... )

- Sunday, March 14, 2004 at 05:40:10 (EST)

Overrated and Underrated

The year-end "Arts and Ideas" section of the New York Times featured an entertaining but uneven piece titled "Judging 2003's Ideas: The Most Overrated and Underrated" (NYT 27 Dec 2003). It was a compilation by Emily Eakin and Felicia R. Lee of comments by "... a handful of writers, scholars and other opinionated people ..." --- most of whom swung for the fences and struck out.

But there were a couple of thoughtful nuggets in the low-grade ore. Among the "Overrated" category entries I salute:

Metaphors have become the verbal equivalent of grade inflation. You are a goddess! Everyone is a hero! (Thanks to Joseph Campbell for that one.) Gods were immortal, ageless and powerful; heroes were extraordinary. No ancient person would have made that mistake. There was only one Hercules.
- Mary Lefkowitz, author of Greek Gods, Human Lives -

... and in the "Underrated" group, my hat goes off to:

To say that honesty is a virtue often underrated in political life is, I realize, like pointing out that the sun rises in the east. But never have the dangers, costs and consequences of concealing or distorting the truth seemed quite so alarming as they have this past year.
The demand for truthful answers to the most essential questions (Did our administration really believe that Iraq was harboring weapons of mass destruction? Will the new prescription-drug plan actually benefit the elderly?) is more and more often dismissed as "partisan" or, worse, "unpatriotic."
Forthrightness and integrity are being made to seem naïve and weak, the moral province of losers, pointless scruples inconsistent with the more manly attributes required to wage war on terror. But what could be more terrifying than the prospect of a society that no longer has the desire, the will, the energy or the ability to distinguish between the truth and the spin that our leaders would prefer us to believe?
- Francine Prose, novelist, and the author of The Lives of the Muses -

(see also Underappreciated Ideas (6 Jul 1999), ... )

- Saturday, March 13, 2004 at 14:32:04 (EST)

Kennedy Center View

The evening is cloudless, crisp, and bright. High in the south stands Orion, Venus on his left hand, the gibbous Moon to his right. A flock of people huddle near the concert hall doorway. Walk 100 feet away, and the balcony is yours alone.

Look down and glimpse a jogger plodding along a riverside trail. Reflected lights from Georgetown and Rosslyn ripple on the Potomac. Cars creep to escape the city via the Key Bridge, the Roosevelt Bridge, the Memorial Bridge, the 14th Street Bridge. Tiny green beacons on the underside of the arches show boats the channel to follow; red pinpricks to left and right indicate where not to navigate.

Lights in the sky form a chain above the river: airliners spaced 90 seconds apart, wending their way downstream, engines grumbling as the planes bank to follow the water's course, flaps back, speed minimized. Each aircraft as it passes the Jefferson Memorial in turn veers right to make a final approach to National Airport.

Across the stream the Pentagon hunkers low. Closer to hand, the Washington Monument pokes a finger at the sky. A pair of red eyes blink sleepily on each of the four sides of the pyramid at its top. In the foreground marble pillars around the Lincoln Memorial glow.

And in the midst of the light and the bustle, directly across the Potomac, all is darkness. Roosevelt Island sits quiet, unlit, a nature preserve. Just beyond it is Arlington Cemetery, where more than a quarter of a million people lie at rest. The Marine Corps Marathon starts and finishes there, at the Iwo Jima Memorial. Its route stretches left and right, downstream and up, across the river, past on the trail below, around the monuments, and back again.

Flowing by: the runners, the traffic, the airplanes, the river. In the center, a silent endpoint ...

- Friday, March 12, 2004 at 16:49:39 (EST)

Bacon Thighs

Chafing --- a common problem for distance runners. The inner thighs are particularly vulnerable. Even the most inoffensive seam in a pair of shorts can, after a few dozen miles, create a nightmare of abrasion. Coating the vulnerable areas of one's upper legs with petroleum jelly helps ... sometimes, for some people.

Now there's a better solution: the new, high-tech yet all-natural answer from the same folks who brought you Pow!r SpüngZ, the ultra-energy fuel --- Bäk!n StripZ.

Yes, just take these cured pork slices (not to be confused with ordinary pieces of uncooked bacon, no matter how similar they may appear) and wrap them around your thighs. Secure them in place with our handy strip-clips (not included), or simply staple them on. The powerful lubricants of Bäk!n StripZ will immediately go to work to protect your delicate parts from discomfort, no matter how far you go. The normal heat that your body generates will, in fact, release additional friction-reducing molecules as they're needed, in a thixotropic phenomenon that our research chemists term "just-in-time goo".

By the way, to allay any concerns of our vegetarian customers: Bäk!n StripZ are produced exclusively from pigs raised in the most luxurious surroundings, fed generous amounts of healthy foods. Our noble swine pass away peacefully of old age after living full, happy lives. So you need have no guilt feelings when you use Bäk!n StripZ --- rather, you can be proud knowing that you are employing a fellow living creature to perform one final honorable, productive mission.

And that's not all! Bäk!n StripZ can significantly improve your speed in both races and training jogs. Just put the StripZ in place as instructed and run past a dog (any breed will do, but Dobermans are ideal). When the animal senses the presence of Bäk!n StripZ and begins to nip at them, you in turn will immediately experience an instinctive desire to run faster and farther than you have ever been able to do before. Try it and see for yourself!

Get Bäk!n StripZ at your favorite athletic supply store --- only $29.95 per pound. Look for them in the refrigerated cabinet. A major portion of our profits from this product go to our legal defense fund.

(see also Power Sponge (18 Sep 2003), ... )

- Thursday, March 11, 2004 at 06:34:58 (EST)

More from 1852

1852 is "my year": it's a century ahead of when I was born, and I continue to collect coins bearing that date. In addition to the tidbits gathered in Numis Trivia Of 1852 (4 Jun 2000) other historical events of that era offer evidence of scientific and societal progress in several dimensions. During 1852:

And perhaps of greatest significance, Frederick Douglass, abolitionist, is named Vice Presidential candidate of the Liberal Party. In Corinthian Hall (Rochester, New York) he gives the speech "What to the Slave is the Fourth of July?" which includes the passage:

"What, to the American slave, is your 4th of July? I answer; a day that reveals to him, more than all other days in the year, the gross injustice and cruelty to which he is the constant victim. To him, your celebration is a sham; your boasted liberty, an unholy license; your national greatness, swelling vanity; your sound of rejoicing, empty and heartless; your denunciation of tyrants, brass fronted impudence; your shout of liberty and equality, hollow mockery; your prayers and hymns, your sermons and thanks-givings, with all your religious parade and solemnity, are to him, mere bombast, fraud, deception, impiety, and hypocrisy --- a thin veil to cover up crimes which would disgrace a nation of savages. There is not a nation on the Earth guilty of practices more shocking and bloody than are the people of the United States, at this very hour."

(for images of some coins in my 1852 collection see http://www.his.com/~z/1852.html = "1852!" and http://www.his.com/~z/gallery1852.html = "Gallery of 1852 Coins". )

- Wednesday, March 10, 2004 at 06:25:38 (EST)

GPS Jogs

A debate broke out recently, in a local running online discussion group, concerning how to measure a race course --- and the likely precision, or lack thereof, for Global Positioning System readings taken along a route. My experience suggests that GPS pathlength estimates tend to be low by 5-10% on winding, twisty, wiggly trails like those which I most enjoy rambling along. But rather than speculate in a vacuum I decide to harvest a few fresh figures. The results tend to confirm my previous skepticism. Adapted from Brian Tresp's Running Blog [1], my notes for the past dozen days of data gathering:

GPS & Leg Tests (Friday 27 Feb)

I went out today for my first jog since the GW B'day marathon, and except for some minor left knee ache all systems seemed fine throughout the 49 minute jaunt. The GPS (Garmin eTrex "Legend" model) that I carried said I covered 4.60 miles, but my estimate is more like 4.8-5.0 based on measured segments and past experience on the route. Along Rock Creek Trail between mile marks 2.25 and 1.25 the GPS distance was 0.94 miles; on the overlapping Marathon in the Parks segment between mile markers 23 and 24 the GPS registered 0.98 miles. I held the receiver carefully so that it got a good signal, and it never appeared to lose lock on the satellites. Its estimated locational accuracy was typically 17 feet. But as Brian and others have commented, GPS seems to be far short of the required accuracy to measure race courses with their twists and turns ...

GPS on Rock Creek Trail (Sunday 29 Feb)

~13 miles in ~155 minutes today, gathering numbers along Rock Creek Trail and the Marathon in the Parks course --- same Garmin eTrex "Legend" model as before --- between Rock Creek mileposts 3 and 7 the GPS measured 0.93 + 0.91 + 0.88 + 0.86 and on the return trip the distances were 0.92 + 0.90 + 0.93 + 0.90 ... average of ~9% short. Between MitP mile 20 and mile 16 and return the corresponding numbers were 0.90 + 0.92 + 0.82 + 0.88 and 0.92 + 0.85 + 0.94 + 0.91 ... ~11% deficit. (But since the courses overlap the data points are not independent.)

Maybe my GPS is using a bad algorithm to estimate distance, or maybe there is something else going on (e.g., user error?!) ... the signals were strong throughout the run (except for brief intervals when the trail goes through tunnels under Connecticut Ave. and under the railroad tracks in Kensington) ... the GPS positional accuracy estimate that the unit displayed tended to fluctuate beteween ~17 and ~45 feet ... as an experiment, after the halfway point I increased the "track sampling rate" to once every 5 seconds --- but although that made a somewhat smoother curve on the built-in map display it did not change the odometer reading errors significantly, as per above data.

So I remain mystified ... but I continue to speculate that my GPS pathlength measurements are low by 5-10% because the unit can’t sense the wiggles in the course ... see Richardsonian Extrapolation and related notes on http://zhurnal.net/ ...

Great Weather (Monday 1 Mar)

"speedwork": 4+ "fast" miles this afternoon (~45 minutes), including a blazing 8:57 along Rock Creek Trail between mile marks 1.25 and 2.25 ... said “hi!” to several babies in carriers and prams ... lots of couples, old and young, out strolling ... noisy squirrels scrabbling in the leaves, geese honking above ... (no GPS this time!)

More GPS (Thursday 4 Mar)

Nice 5+ miles late this afternoon, ~10:30 pace, no walk breaks ... from home to Georgetown Branch Trail to MitP route, then back via Walter Reed Annex ... on the measured segments, the GPS again was quite low, in spite of strong satellite signals: its odometer claimed 0.96 mi. for MitP 24-23 and 0.90 mi. for MitP 23-22 (and I followed the correct route; the crushed stone on the detour east of the creek near the Beltway was great --- no mud wallows there any more) ... I lowered the “track sample” rate to 0.01 miles before starting but that had no apparent effect on the results ... superb weather ... frogs peeped loudly in the swamps near Rock Creek ... many cyclists ... team of young girls practicing lacrosse at Ray’s Meadow Park ... little kids rushing to pet a shaggy dog near the play area ...

GPS on the GBT (Friday 5 Mar)

8+ miles, ~93 minutes on the Georgetown Branch Trail ... unseasonably warm ... fire engines race past on Brookeville Road, sirens howl from near Meadowbrook Stables, and then more rescue vehicles come from the other direction via Jones Bridge ... at the turnaround an almost-full Moon rises between high office buildings in downtown Bethesda ... a bat flitters overhead at Columbia Country Club as twilight deepens ... the Moon plays peek-a-boo with the clouds (and the clouds soon win) ... a welcome wind rises as I make it home without twisting an ankle on the jumbled ruts in the first mile of the trail ...

The Georgetown Branch is relatively straight; more GPS tests, with “odometer” measurements recorded at the half-mile markers (0.5, 1.5, 2.5, 3.5, and then the reverse) give results in miles = 0.97 + 0.95 + 0.98 + 1.03 + 0.93 + 0.93 for an average of ~4% low. I took the straight-line crossing of Connecticut Ave. along the train tracks, but followed the crosswalks in Bethesda. Satellite signals were strong, but obviously I lost them for ~0.2 miles in the tunnel under Wisconsin Ave. The unit apparently took that into account in estimating distance. I increased the "track sampling" rate to 1/second, without much apparent effect on precision.

W&OD GPS (Sunday 7 Mar)

Big accident on Beltway at 0630 this morning as I set off for northern Virginia --- at Georgia Avenue, 6 cars smashed up, surrounded by a similar number of police cruisers (lights flashing) plus an ambulance and a fire engine ... I circumnavigate and proceed west, full Moon hanging huge in front of me, to the W&OD Trail (caboose parking lot in Vienna) where comrades SA & CR join me ... pleasant 10+ mile jog starting before milepost 12 and proceeding to milepost 17 and back ... cool and clear, few other runners and cyclists at 7am but increasing numbers of them as we return ... average pace ~10:30 min/mi outbound, accelerating to ~10:00 min/mi returning (as a group of young ladies passes us and motivates us to go faster) ... beer and omelettes at the Vienna Inn help us recover afterwards ...

GPS measurements for first nine miles only (since when the display passes the 9.99 mi point it stops showing hundredths of miles): 0.97 + 0.97 + 0.99 + 1.00 + 0.99 to turnabout + 0.98 + 0.99 + 0.99 + 0.99 ... net average only ~2% low, much closer than typically seen along the Marathon in the Parks route, Rock Creek Trail, and Sligo Creek Trail ... probably so accurate because the W&OD is almost a straight line, with only gentle curves in this section ...

Brisk Jog (Monday 8 Mar)

Winter comes back ... the robins are bobbin' and rockin' as they discover it isn't Spring yet and hop about, trying not to blow away ... ~6 miles in ~63 minutes on Rock Creek and Georgetown Branch trails, with timed segments MitP miles 22-23 = 9:54 and 23-24 = 10:01 --- wish I could go that fast at that point of the marathon! Beach Drive is blocked off between Stoneybrook and Connecticut; I catch a whiff of sulfurous smell east of the water fountain at Old Spring Road ... is it a leaky natural gas pipeline? sewage overflow? swamp gas?

GPS batteries are depleted and finally die in the cold, but I get one measured mile (MitP 22-23) which the odometer records 8% low ... setting sun flares crimson beneath horizontal cloud bands as I approach home ...

(see also Coordinate Collection (19 May 2002), Rock Creek Trail (31 May 2002), Marathon Coordinates (3 Oct 2002), Marine Corps Ordnance (1 Nov 2002), Anacostia Tributaries (28 Jan 2003), Ten League Ley Lines (23 Nov 2003), Lincoln Memorial (6 Jan 2004), ...)

- Tuesday, March 09, 2004 at 06:00:56 (EST)

Montaigne Essays

Yet another classic author whom I haven't yet read: Michel de Montaigne (1533-1592). Recently I learned that he virtually invented the "essay" --- a word that comes from the French essai = attempt, Montaigne's self-effacing description of his efforts. Ya gotta salute that kind of modesty! So to the used-book-sale I hie myself, and there among a variety of editions I find one that is not only inexpensive but also comes with a built-in story.

It's a falling-apart volume, a tiny 1949 Modern Library tome. Inside the front cover a bookplate announces "EX LIBRIS Roxie Marie José". On one of the blank pages at the back of the book is written in a lovely hand, "This book was given to me by my husband. He knew full well how much I'd enjoy it!" and then the inscription "R. M. José from E. M. J."

Inside the front cover the same handwriting records, "It is said this is the only book William Shakespeare possessed." Sewn --- yes, stitched with a thick black thread --- to the copyright page is a magazine clipping that quotes Dorothy Parker "in Esquire, on Historical novels: I wish people would either write history, or write novels, or go out and sell nylons." The Table of Contents has a red checkmark next to Montaigne's essay "Of the Education of Children". Glued onto the inside back cover is a paragraph, cut with care from another source, bearing the words of Henry David Thoreau:

How many a man has dated a new era in his life from the reading of a book. The book exists for us perchance which will explain our miracles and reveal new ones. The at present unutterable things we may find somewhere uttered. These same questions that disturb and puzzle and confound us have in their turn occurred to all the wise men; not one has been omitted; and each has answered them according to his ability by his word, and his life.

Throughout the book favorite passages are underlined, and accompanied by marginal notes on occasion. Some leaves are stained by chemical oxidation, yellow shadows of newsprint left too long in contact with the pages. A DC Transit System bus transfer dated 17 November 1958 is tucked between pps. 134 and 135. A gum wrapper marks p. 454. A scribbled note leads to p. 318, where an indented verse bracketed in red says:

     The man lives twice, who can the gift retain
     Of memory, to enjoy past life again.

Beside that is written, "Women also".

The book tends to fall open to page 218, towards the end of Montaigne's essay "Of Presumption", where marginalia in pencil admonish "Note here" beside the sentence:

Whether, perhaps, it be that the continual association I have with the ancients' ways of thought and the idea I have formed of those richly endowed souls of past ages give me a distaste both for others and for myself; or whether, in truth, we live in an age which produces only very mediocre things; the fact remains that I know nothing worthy of great admiration.

Fascinating, to see footprints left in the dust by a previous explorer in these ancient caves of thought ...

(see also Charlotte Haven Lord Hayes (25 Dec 2003), ...)

- Monday, March 08, 2004 at 06:12:39 (EST)

Magnetohydrodynamic Aphorism

"Googlewhacking" [1] is the sport of finding a unique web page in response to a two-word Google [2] search. (Note that in a genuine googlewhack the two words must be legitimate dictionary entries, the search must be performed boolean-AND fashion rather than as a quoted phrase, and the one-of-a-kind result must not be a word list, encyclopædia, dictionary, or other unnatural collection of strings.)

A fortnight ago Matthew Whyndham [3] --- fast marathoner, space physicist, and fascinating fellow --- introduced me to googlewhacking with the news that his quest for magnetohydrodynamic aphorism had led him to the singular hit ^zhurnal v.0.33 [4]. (Of course, posting that fact here will render it nugatory as soon as Google indexes this page. Tough luck!)

By pure coincidence, in a message yesterday Amanda Williams [5] used the word reify, one of many splendidly arcane philosophical terms that tickle my inner ear whenever I see them. Hitherto reification hasn't appeared in the ^zhurnal. (It's the act, or fallacy, of treating an abstract concept as if it were a concrete thing. Now I've mentioned it; check that box off.) Another philosopher's term-of-art that I dearly like the sound of is supererogatory --- describing acts that go beyond what can be required or expected of one. Amanda's kind note triggered some neurons to fire in the old cranium, and a few mental-clock-cycles later a search for reifies supererogation led me to the googlewhackish "Environment, Beauty and Bible", by F. Gerald Downing [6]. (Sorry, it won't be a unique Google result once I've posted this.)

Downing's fascinating essay begins with a bit of heavy theology but picks up speed as it progresses. His discussion of Biblical poetry and of the Song of Solomon in particular is happy, thoughtful, and lovely. "Imagining a young couple imagining unrestrained delight in one another opens up a vision of the ordinary world surpassed." So sweet, and so true.

But alas, "Environment, Beauty and Bible" as currently posted is marred by a distracting typo in the second sentence of the Abstract:

Is 'beauty' an 'ecotheological' issue? Or, specifically, is the Cod of the Judaeo-Christian Bible concerned only with the ‘goodness’ of creation, not its beauty? ...


(I've attempted to notify the site administrator; perhaps it will be fixed soon. See also On Supererogation (18 Dec 1999), Ink Blots (18 Sep 2001), Rainposts And Godrays (23 Sep 2002), Flying Finn (18 May 2003), ... )

- Saturday, March 06, 2004 at 17:47:25 (EST)

Cut the Volume

Conflict-aversion is my middle name --- so why do I like the movie Fight Club so much? Maybe because it (or more precisely, the novel by Chuck Pahlaniuk that the film is based on) brings so many extraordinary aphorisms to the table. There are pointed critiques of modern consumerism:

... plus get-down-to-earth remarks about living:

... thoughts that resonate (in a hugely exaggerated way) with my jogging experiences:

... off-the-wall anarchistic observations:

... and the #1 favorite, most important and relevant of all:

That's precisely the feeling one achieves, not from bashing another person (which I hope never to do or witness), but rather after a variety of simple, healthy, strenuous, focused, and profoundly satisfying activities --- whether physical or mental.

Every person's path is different, and changes from day to day. For me, right now, a long quiet run through the woods is a prime way to invoke the magic. It attenuates that constant buzz of all the lightweight ephemeral stuff, and creates a chance to relax and attend to important things ...

(see also Conflict Aversion (22 Feb 2000), Dialogue Density (21 May 2002), Good Day (25 Jun 2002), Welcome To The Club (11 Jun 2003), Fight Club (15 Jun 2003), ...)

- Friday, March 05, 2004 at 06:32:45 (EST)

Over Qualified

Maximum efficiency is all well and good, when a task is mind-numbingly predictable. But in the real world, if you're trying to do something important --- which by definition means that the job and the environment are unpredictable --- then it's vital to have overqualified people on a project. They're the ones who will bring creativity to bear, and thus save the ship, when a sudden crisis hits the fan. They're also the ones who will have mental "engineering reserves" available in ordinary circumstances, so that they can keep up with all the usual work and still have headroom to think about improvements to the system.

Yeah, they're obnoxious, disrespectful, and tough to manage. They look like lazy bums most of the time. You've gotta pay them too much. Your boss will complain.

But the more critical a mission is, the more grossly-overqualified a crew you'd better assemble, if you want to succeed.

(see also One Deep (15 Nov 1999), Project Management Proverbs (2 Jun 2002), ... )

- Thursday, March 04, 2004 at 05:41:33 (EST)

Maracthonic Metaphors

The most grossly overemployed buzzword of our era? It has to be marathon, to describe anything implied to be long, overwhelming, stressful, and/or boring (which a 42+ kilometer jog is not, or need not be).

Examples seen in the press during the past fortnight include:

The list is growing, and may someday itself be a "marathonic" reading exercise.

An entertaining experiment: search for "marathon" in your favorite well-indexed newspaper or wire service. Note how often the word occurs, not counting instances associated with 26.2 mile footraces (or proper nouns such as the Marathon Oil Corporation, the movie "Marathon Man", etc.). My unscientific survey last month found metaphorical marathons in more than a third of the daily issues of the New York Times and in over half of the of the Washington Post dailies. And the density seems to be rising.

A tricky challenge: design a boolean query for news media or web search engine which finds at least 80% of the appearances of "marathon" meaning 26.2 mile run, but retrieves fewer than 20% of the other usages of the term. Not easy, in my experience.

Finally, a modest proposal: reserve the word "marathon" for the classical plain in Greece and the footrace. For literary descriptions of lengthy and tiresome phenomena, try maracthonian --- from "mara" = evil spirit + "cthonian" = of the underworld. The demon of purple prose will certainly approve!

- Wednesday, March 03, 2004 at 06:30:57 (EST)

Ai Ren

Political correctness is a many-splendored thing. After taking charge in 1949 the communist rulers of China started simplifying and "reforming" the language. Instead of the classic and arguably-sexist Chinese words for wife and husband, a new genderless term was promoted: airen (or ai ren), built from the characters for love + person and taken to signify spouse.

Airen came to mind again recently when one of my favorite words arose in correspondence with a friend. That word is "celibate". It bears sparkling and quasi-archaic associations with holy orders, musty monasticism, cowled figures, and massive mossy stone walls. (No jokes, please, about how the best way to achieve celibacy is to marry!) A quick peek in an old out-of-copyright dictionary found, for "celibate", the Latin sources "cælibatus, fr. cælebs, unmarried, single" --- plus fortuitous entries above and below it: celiac (or cœlliac) = "relating to the abdomen, or to the cavity of the abdomen", and celidography = "description of apparent spots on the disk of the sun, or on planets". Neat terms, eh?!

But let's get back to airen, which I innocently learned ca. 1975 during my initial self-study of Chinese. I was exploring the language via some cheap Beijing Central Radio Station tapes and books that I had snagged at a store in Los Angeles' Chinatown area. A year or two later I took some evening Chinese classes at Pasadena City College, a few blocks from Caltech where I was a grad student. (I signed up at PCC in hopes of meeting some interesting women ... but fortunately or unfortunately had no such luck!) The teacher told me gently that "airen" grates on the ear of a non-mainland-Chinese person, or for that matter almost any native speaker from an older generation. To them, the word denotes "sweetheart", "mistress", or "lover" ... and brings with it a blush.

In fact, by the 1980's the linguistic tide had already begun to recede. Now "airen" is largely back to its former meaning, in the People's Republic as well as elsewhere. I happened to have learned it at precisely the wrong moment. Oops!

(see also College Collage 3 (29 Sep 2001), ... )

- Tuesday, March 02, 2004 at 05:56:35 (EST)

Iridium Transit

Coincidences are, almost by definition, unusual. They're also fun! In astronomy there are several major types of coincidence that are striking enough to bear unique names. A conjunction occurs when a couple of moving objects (e.g., planets) come together in the sky, to a greater or lesser degree of closeness. Since there are quite a few moving objects this happens almost all the time. Rarer is an occultation, the passage of a nearby and apparently-large body (like the Moon) in front of a distant bright object (such as a star or planet). Lunar occultations take place many times per month, though the more dramatic ones that are easily seen by naked eye or through binoculars only happen a few times annually. An eclipse is an occultation involving both the Sun and the Moon.

More exotic is a transit, as a little body crosses the face of a more distant but bigger one. The satellites of Jupiter, for instance, can often be seen with a telescope as they creep across the disc of that planet. From Earth the only possible planetary transits with the Sun involve Mercury and Venus, since they're the only planets with smaller orbits. Mercurial transits happen every several years, but Venereal (sorry, that's the proper adjective) events are much rarer. A pair of them takes place less than once per century. We're lucky --- one is due on 8 June 2004.

The existence of artificial satellites makes a new kind of transit feasible: the passage of a tiny man-made artifact in front of the Moon. Most of those won't be visible except with large telescopes.

But there's an exception. Certain communications satellites have large flat antennas which, at the right moments, can reflect sunlight down with brilliant intensity. These so-called Iridium Flares cause a glint brighter than any star or planet. But the spectacle only lasts for a few seconds.

Now what if an Iridium flare occurred just as the satellite in question were passing in front of the Moon? That would be true drama! I haven't been able to learn whether any such Iridium transits have been observed, and they should be extremely rare --- but there's no reason for them not to exist. My rough guess is that, within 50 miles or so of any given location, there might be an Iridium Lunar transit visible once every few years. I want to see one!

(see also Coincidental Taxonomy (19 Oct 2001), Iridium Flares (30 Dec 2001), Coincidental Taxonomy 2 (14 May 2002), Saros Cycle (6 Nov 2003), ... )

- Monday, March 01, 2004 at 06:33:46 (EST)

Diary Benefits

In "Finding Philosophy" Colin McGinn reminisces:
... Above all, I learned a very valuable lesson, one that had hitherto escaped me: make notes. When reading a book, or listening to a lecture, or even just ruminating, put the salient points down on paper: this will fix them in your mind, give them firm expression, and provide a quick and easy way to recall what you earlier learned. Simple, I know, but even today I notice legions of my students sitting through lectures without pen in their hands. Thinking and writing should be indissoluble activities, the hand ministering to the thought, the thought shaped by the hand. Today, if I find myself without pen and paper and thoughts start to arrive, my fingers begin to twitch and I long for those implements of cogitation. With such rudimentary tools you can perform the miracle of turning an invisible thought into a concrete mark, bringing the ethereal interior into the public external world, refining it into something precious and permanent. The physical pleasure of writing, which I find survives in the use of a computer, is something worth dwelling on in matters of education.
Around this time I started to write a diary, chiefly as a way to practice my writing skills. Since there is no need to monitor the quality or interest of what is being written, the diary is an ideal form for developing the technique of writing, and for taking the anxiety out of it. No one will correct your grammar and spelling, or make fun of your naive thoughts and banal phrases, so you are free to get on to friendly terms with the language you speak. I would often try out new words I had learned --- the dictionary had become my friend, rather than a standard I was failing to live up to --- secure in the knowledge that solecism would not lead to embarrassment. A few hundred words a day, complemented by steady reading, will soon produce a passable prose style. The habit of daily reflection also fosters a critical sense, and an articulacy about what is going on; moral acuity can grow from this, as well as self-knowledge. Yes, a diary can seem like self-indulgent wallowing in the trivial details of day to day life, but it is the form, not the content, that counts. I have never read any of my old diaries, and I haven't written one for over 20 years, but I do think that composing them helped teach me how to write and even how to think. Everyone should have one, starting young.

(November 2003, Prospect magazine [1]; see also Thinking Tools Defined (6 Apr 1999), Annals Of Journals (4 Apr 2000), Dear Diary (19 Mar 2001), Zhurnal Anniversary 2 (4 Apr 2001), Writing Rewards (9 Jun 2001), Triple Thrills (11 Jan 2003), Colin McGinn (30 Oct 2003), ...)

- Sunday, February 29, 2004 at 07:46:53 (EST)

Third Normal Form

Yet another concept that I wish I could properly understand: third normal form. I think it describes a database schema that's well-factored, with a place for everything and without redundancies among the various tables and records and fields. But then there are other "normal forms" --- and I have to admit that I can never hold the distinctions among them in my mind for more than a few days, at most.

For me it's just like the proof of Gödel's theorem, or conjugations and declensions in Latin, or the notions used to build the hierarchy of infinities in set theory, or the details surrounding a host of other philosophical-mathematical-linguistic ideas. I'm starting to believe that my mental stack must get corrupted when I try to push too many levels of abstraction onto it ... and the old ^z neural network retaliates by quietly discarding the buffers, resetting the pointers, and leaving me back in my usual befuddled state!

(see also Mysteries Versus Secrets (23 Sep 1999), Millennium Math (5 Dec 2002), Mystery To Me (30 May 2003), ... )

- Saturday, February 28, 2004 at 08:36:08 (EST)

Unfortunate Misparsing

The lead sentence of a front-page article in yesterday's New York Times had a final clause that was seriously misprocessed by a majority of readers in our household:
The United States military is facing the gravest accusations of sexual misconduct in years, with dozens of servicewomen in the Persian Gulf area and elsewhere saying they were sexually assaulted or raped by fellow troops, lawmakers and victims advocates said on Wednesday.

It's a tragic topic --- and it's also a tragic sign of the times when one's mental language-processing software automatically assumes that lawmakers are potential rapists, and that the phrase "... fellow troops, lawmakers and ..." is most probably the beginning of a list of perps ...

(see also Achieve New Balance (17 Jul 2002), Mary Landers For Mathias (25 Aug 2002), Close To The Pin (5 Jan 2004), Oxford Commas (25 Jan 2004), ... )

- Friday, February 27, 2004 at 18:35:42 (EST)

Daily Presents

Vision by David Marr is a fascinating textbook that explores the ideas behind computer (and perhaps also human?!) visual pattern recognition. Marr explains his theories and research plans in a lucid and technically-detailed fashion. Among the host of powerful metaphors that he develops is the delightfully-named "two-and-a-half dimensional sketch" --- a halfway house between the flat image on a retina (or focal plane) and the full 3-D model of reality.

But there's a special poignant aura surrounding Vision. As he wrote it, David Marr knew he was soon to die of acute leukemia. He threw his energy into the work; it remains one of his monuments. And I thought of Marr when, standing in a bookstore, I glanced at the preface to one of Robert Nozick's last philosophy tomes. Nozick acknowledges the contributions of various people, and among them thanks his oncologist for giving him a few more years.

Life: every day a gift ...

(see Bennett On Stoicism (29 Apr 1999), Robert Nozick (2 Feb 2002), Very Good Day (7 May 2003), ... )

- Thursday, February 26, 2004 at 07:37:02 (EST)

Chandra Stories

Chandra: A Biography of S. Chandrasekhar by Kameshwar C. Wali, a 1991 book about the great astrophysicist, is rich with zen-like anecdote and insight.

from the Prologue (told to the author by Carl Sagan):

Chandra was giving a colloquium. Three walls of the lecture room had blackboards on them, all spotlessly clean when Chandra began his lecture. During the course of his lecture, he filled all the blackboards with equations, neatly written in his fine hand, the important ones boxed and numbered as though they had been written in a paper for publication. As his lecture came to an end, Chandra leaned against a table, facing the audience. When the chairman invited questions, someone in the audience said, 'Professor Chandrasekhar, on blackboard ... let's see ... 8, line 11, I believe you've made an error in sign.' Chandra was absolutely impassive, without comment, and did not even turn around to look at the equation in question. After a few moments of embarrassing silence, the chairman said, 'Professor Chandrasekhar, do you have an answer to this question?' Chandra responded, 'It was not a question; it was a statement, and it is mistaken,' without turning around.

from Chapter 1 (a favorite story told by Chandra to his students):

There were five princes. When they were taking archery lessons from a famous master, one of the five princes became known as the greatest of them all. On one occasion, a visitor --- a wandering minstrel --- comes to the archery school and sees the five princes practicing. To him all of them appear extraordinarily good, nothing discriminates one from the other. When he encounters the master with his observation and asks him why one is picked as the greatest, the master leads him to the five princes. The master asks each prince to take aim at, but not shoot, the eye of a bird sitting on a tree. When they are ready, he asks each of them, 'What do you see?' The first prince says he sees the bird's eye, the tree branches, flowers, and the sky beyond. The second prince narrows the list somewhat, but when it is the turn of the prince who is known to be the best archer of them all, he says, 'Revered master, it's strange. I don't see anything except the eye of the bird.'

also from Chapter 1:

Another one of Chandra's stories that many of his students heard was that of a milkman on his way to deliver milk in the early morning. His milk cart hits a rock on the road and topples over, spilling all the milk. The man of course gets upset, curses profusely, but proceeds on his way. A little later, a mother is taking her son to school. The boy stumbles over the rock, is hurt, and starts crying. The mother curses the rock and proceeds. This continues all morning --- people stumbling, falling, and cursing. All this time, a blind beggar sitting at the side of the road wonders why all these people are cursing but doing nothing to remove the obstacle from their path. Finally, at noon, when there is a lull in the traffic, he gets up and removes the rock. To his surprise, he finds a bag of gold underneath it.

(see also Redundancy Redundancy (23 Apr 1999), Late Physicists (24 Sep 2000), ... )

- Wednesday, February 25, 2004 at 18:34:13 (EST)

Data Structures

In the battle for mindshare some topics have all the luck. Skyscrapers make the magazine covers; sewage treatment plants, infinitely more important for public health, get ignored. Likewise when it's celebrities versus schoolteachers, or space programs versus trees, or pills versus exercise.

In the computer science world, algorithms are the sexy headliners. Quicksort! Simplex Method! Backpropagation! Predictor Corrector! Fast Fourier Transform! LU Decomposition! The best way to get your name carved into the CS wall of immortality is to chisel it onto a clever algorithm.

But data structures are the really essential yet oft-overlooked foundations of programming. Put together bits to make numbers and letters. Arrange numbers and letters into vectors and strings. Build lists by linking together pointers and cells. Construct arrays and queues, heaps and trees, hashes and graphs ... and move onward to higher levels of abstraction and power.

"Show me your code and conceal your data structures, and I shall continue to be mystified. Show me your data structures, and I won't usually need your code; it'll be obvious."

(the quote is an Eric Raymond (1997) paraphrase of Frederick Brooks (1975); see Guy Steele in [1]; see also On Duals (2 Dec 1999), John Tukey (31 Jul 2000), Programming Proverbs (4 Dec 2001), Richardsonian Extrapolation (18 Apr 2002), ... )

- Tuesday, February 24, 2004 at 09:51:45 (EST)

Washington's Birthday Marathon 2004

The 22 February 2004 George Washington's Birthday Marathon continues an ominous trend: I finish in 5 hours 12 minutes, ~8 minutes slower than I covered the same distance in November 2003, which is in turn ~8 minutes slower than November 2002's experience. Oops!

But for somebody as woefully under-trained as I am, it's a not-unexpected result. Again I fail to achieve the elusive "negative splits", but at least I'm only ~4 minutes slower for the second half of the run than I am for the first.

The race is great fun and singularly cost-effective (less than $1/mile for early registrants). I meet a variety of nice people along the way, and my knees and ankles suffer no major damage. The organizers and volunteers are uniformly enthusiastic and helpful. The course is entertaining (albeit somewhat hilly), three loops along the roads of the Beltsville Agricultural Research Center, with a couple of miles before and after to connect to downtown Greenbelt. Weather is near-perfect, with temperatures in the low 40s Fahrenheit.

This event features a brilliant innovation: an optional early start for those who are impatient to go. A few runners start 90 minutes before the official kickoff time; I begin with a cohort 60 minutes in advance of schedule. This lets me see some of the elite runners (as they pass me!). It also gets me to the finish line in time to applaud the winners at the award ceremony and scarf down some (veggie!) chili, fruit, cookies, etc.

Encounters and Acquaintances

Random Commentary

Gory Numerical Details

Alas, I forgot my GPS receiver at home, so no latitudes or longitudes. But here are splits and cumulative times captured by my watch at the course markers:
Mile Time Pace Mile Time Pace Mile Time Pace
01 0:10:05 10:05 11 2:09:55 11:22 21 4:05:56 11:54
02 0:20:52 10:47 12 2:21:11 11:16 22 4:18:36 12:40
03 0:32:26 11:34 13 2:32:32 11:21 23 4:32:14 13:39
04 0:43:42 11:15 14 2:43:20 10:48 24 4:44:45 12:19
05 0:55:34 11:52 15 2:55:27 12:08 25 4:57:02 12:18
06 1:07:49 12:15 16 3:07:08 11:41 26 5:09:12 12:09
07 1:19:53 12:04 17 3:19:16 12:07 26.2 5:11:17 09:31
08 1:33:35 13:42 18 3:29:26 10:10
09 1:45:35 12:00 19 3:42:17 12:51
10 1:58:35 13:00 20 3:54:02 11:45

Half-marathon time = 2:33:40

Least-squares fit to pace data (omitting final 0.2 miles):

(time & pace for mile 10 were estimated, as was the mile 11 pace --- alas, I missed the mile 10 marker; see also Bless The Leathernecks (28 Oct 2002), Rocky Run (17 Nov 2002), Marathon In The Parks 2003 (11 Nov 2003), ... )

- Monday, February 23, 2004 at 06:34:36 (EST)

Bad Arithmetic

Numbers are keys to knowledge. As William Thompson (aka Lord Kelvin) famously said:
When you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meager and unsatisfactory kind: it may be the beginning of knowledge, but you have scarcely, in your thoughts, advanced to the state of science."

As is probably obvious from many of the posts here, semi-quantitative analysis is one of my bags. On a related theme, recently Darren Neimke kicked off a discussion of metrics for programmer productivity (in http://weblogs.asp.net/DNeimke --- see "Lies, D*mned Lies, and Statistics"). Many other examples of the power of numbers in a visual context are offered in Edward Tufte's classic books (see Tufte Thoughts (18 Dec 2000)).

But numbers, used incorrectly, can be worse than useless in advancing one's understanding of a topic. For instance, an op-ed piece by a famous columnist caught my eye earlier this week. The author wanted to suggest that the wealthy are being overtaxed, and as "proof" reported, "In 1979 the top 1 percent of earners paid 19.75 percent of income taxes. Today they pay 36.3 percent."

Well, duh! That's absolutely the wrong computation to make. The fraction of total tax revenues that the top 1% pay does speak volumes about income distribution --- and the rise in that percentage implies an increasingly skewed concentration of wealth. (Think: if 99% of the population had zero income, then the top 1% would pay all of the taxes, no matter how low the tax rates might be.) In fact, a quick check of the Statistical Abstract of the United States (2003 edition, Table No. 688) shows that the top 5% of all families received 14.6% of aggregate income in 1980 but increased that share to 21% by 2001. Adjusted Gross Income is even more sharply peaked; the share of AGI received by the top 1% rose from 8.5% in 1980 to 17.5% in 2001. (The popping of the dot-com bubble hurt the top 1% somewhat; their share was a bit higher during 1998-2000.)

The number that an honest author should have quoted is the fraction of the income of the top 1% that is taken by taxes. In 1980 that tax rate was 34.5%; it fell to 27.5% in 2001. So the tax burden on the wealthy has arguably fallen, moderately, during the past two decades. (source: Internal Revenue Service data, presented by the Tax Foundation, Inc.; note that tax law changes in 1986 account for part of the difference)

This is the same kind of statistical fallacy that often crops up in criminal DNA evidence arguments, or in analyses of the benefits of vaccination, or in a countless number of other places. When taking ratios, you've gotta do them in the right direction, and when you're done, you've gotta think about the results ...

(see also Science Versus Stamp Collecting (20 Jun 2000), Basement Worries (15 Jun 2002), Modern Phrenology (19 Oct 2003), ... )

- Sunday, February 22, 2004 at 07:28:37 (EST)

For back issues of the ^zhurnal see Volumes v.01 (April-May 1999), v.02 (May-July 1999), v.03 (July-September 1999), v.04 (September-November 1999), v.05 (November 1999 - January 2000), v.06 (January-March 2000), v.07 (March-May 2000), v.08 (May-June 2000), v.09 (June-July 2000), v.10 (August-October 2000), v.11 (October-December 2000), v.12 (December 2000 - February 2001), v.13 (February-April 2001), v.14 (April-June 2001), 0.15 (June-August 2001), 0.16 (August-September 2001), 0.17 (September-November 2001), 0.18 (November-December 2001), 0.19 (December 2001 - February 2002), 0.20 (February-April 2002), 0.21 (April-May 2002), 0.22 (May-July 2002), 0.23 (July-September 2002), 0.24 (September-October 2002), 0.25 (October-November 2002), 0.26 (November 2002 - January 2003), 0.27 (January-February 2003), 0.28 (February-April 2003), 0.29 (April-June 2003), 0.30 (June-July 2003), 0.31 (July-September 2003), 0.32 (September-October 2003), 0.33 (October-November 2003), 0.34 (November 2003 - January 2004), 0.35 (January-February 2004), 0.36 (February-March 2004), 0.37 (March-April 2004), 0.38 (April-June 2004), 0.39 (June-July 2004), 0.40 (July-August 2004), 0.41 (August-September 2004), 0.42 (September-November 2004), ... Current Volume. Send comments and suggestions to z (at) his.com. Thank you!