brainwagon

Old timers may remember Byte magazine, and Steve Ciarcia’s column therein. Steve went on to publish Circuit Cellar magazine, an electronics magazine which is more or less dedicated to embedded computer systems. Byte books published a book of his called “Build Your Own Z80 Computer”, which now can be downloaded in its entirety with Steve’s Permission from scribd or Google Books.

Why would anyone want this book? After all, the Z80 is pretty primitive compared to even microcontroller chips like the Atmel ATMega series or PICs. For me, it’s a return to my computing roots; a chance to do something that I couldn’t do back then. Z80 parts are still available and inexpensive, and you can still learn a lot about computers by tacking one of these things together.

Build Your Own Z80 Computer.

I love Sherlock Holmes. I think that Conan Doyle’s portrayal of London’s most famous fictional detective are some of the most fun and yet also most artful works of detective fiction ever written. The only pity is that there aren’t more of them.

For fun, I picked up a copy of New Sherlock Holmes Adventures, edited by Mike Ashley. I’ve been reading them over the past few days, and I’m sad to reveal that the absolute best of them pale in comparison to the worst of the originals by Conan Doyle. You’ll find all sorts of stories which are pale imitations of stories conveyed with greater impact by Doyle, stories which detail Holmes interacting with famous characters like H.G. Wells (in a plot line which more properly belongs to the world of science fiction), and stories in which Holmes finds radium in an old funeral barrow. Unlike the artful work of Conan Doyle, the plot lines are either obvious or pulled out of the aether as if by magic, and none are satifying.

A complete waste of time. I hardly ever sell books, but this one is going to Goodwill.

[tags]Book Review,Sherlock Holmes[/tags]

Sometimes you find a book that seems uniquely written for your interests: such is Baseball Hacks, the latest O’Reilly book in their illustrious “Hacks” series. It is basically a manual on how to use computers to fuel your obsession for baseball statistics, and includes a wide vareity of cool things you can do with a computer, access to the internet, and open source tools like MySQL and perl. I’ll say more when I’ve had a chance to work through some of the examples.

[tags]Baseball Hacks,Baseball[/tags]

Just in case you didn’t have enough to worry about on this fine Thursday, check out this interesting article:

Damn Interesting » Parasites on the Brain

Toxoplasma gondii may be the most prevalent human parasite. As many as 50% of humans worldwide, and up to 80% in urban areas, have been infected with it at some time in their lives. An estimated 60 million people in the US have active cases at any given time. It’s a single celled parasite whose favored host is cats. However it can infect and live in a host of other creatures including rats and humans. Most infected people, and most infected rats, show no particular signs of illness when infected. They continue on with their daily life and work completely unaware they’ve been parasitized. But they may not be as unaffected as they seem.

You could also pick up the book  Parasite Rex by Carl Zimmer for more fun parasite information.  It’s part of my bookshelf that justifies my increasing paranoia about squishy things in biology.
[tags]Parasite,Brain,Carl Zimmer,Parasite Rex[/tags]

I just finished listening to Dan Brown’s The DaVinci Code and I can’t help but shake my head and wonder:

Why the hell is this book so damned popular?

Dan Brown is a dreadful writer.   Not just mediocre.  But bad.  Really bad.   I mean really, let’s open with an evil albino?  Why not just have a midget and a one armed man as villains?  Dear Lord.

And the code stuff?  They are riddles, not codes.

And the ending.  Dreadful.   Truly dreadful.

[tags]The DaVinci Code[/tags]

For quite some time, I’ve been meaning to read Simon Winchester’s book Krakatoa: The Day the World Exploded: August 27, 1883, but haven’t had the time. Now that I finally got a CD player instlled in my Expedition though, I decided to purchase it as an audiobook, and have been enjoying it during the hour or more I spend in the car each day.

It’s a terrific book, of far reaching scope and depth. Someone with a short attention spam might call it meandering, but I find it to be an interesting look into the historical, scientific and political climate surrounding the eruption of 1883. Sidelines include a brief history of and introduction to the science of plate tectonics, a history of the Dutch and British colonization of the East Indies, and the role that the disaster at Krakatoa may have played in the rise of Islamic unrest in the region. If you are looking for a cheap thrill, pick a shorter book, but this one seems to be like a satisfying meal to me: nourishing the reader listener with knowledge and insight that goes rather deeper than just “volcano go boom!”

Oh, and Winchester narrates his book, he’s got a very nice British accent which is pleasant to listen to. I suspect I’ll be picking up several more of his books.

[tags]Book Review,Audio Book,Krakatoa,Simon Winchester[/tags]

I’m currently reading ::amazon(“0670033847″, “The Singularity Is Near”):: by Ray Kurzweil, and it’s kind of an over-the-top utopian view about the future. His basic hypothesis is fairly radical: that the accelerating innovation in the world will result in a vast leap in human evolution in the 21st century.

I don’t know that I buy the hypothesis, but I’ll address that more in a later post. Today’s idea for the day was on depreciation. Much of our current economy is tied up in technologies which will be realistically only worth half as much in as little as 14-18 months (namely, computer power). No other capital investment depreciates this quickly, and yet the overall industry is the very model of growth. This is because unlike the old historical economic view, computers aren’t capital assets, they are resources: exploitable resources whose price is racing to the bottom, and who is carrying many other industries (biomedical, communications, and manufacturing) straight to the bottom with them. This “deflation” that we fear in (say) the price of our homes is actually driving innovation and economic expansion.

I just hadn’t thought of it that way before.

I’m currently reading Poundstone’s book Fortune’s Formula, and am up the the part which discusses the French mathematician Bachelier, and his thesis that the prices of stocks in the market follow a random walk. His thesis was published in 1900, and slept for quite some time until resurrected after his death in 1946. A bit of googling revealed that you can get his thesis here, in French. NUMDAM is apparently a project to provide digital versions of many old mathematics papers published in French journals. Cool.

Now, I’ll have to dust off my high school French.

I picked up a new book on my trip to Reno: Extra Stuff: Gambling Ramblings by Peter Griffin. Griffin is the author of one of my favorite books in my collection of books on gambling topics: The Theory of Blackjack. This book includes all sorts of interesting tidbits of gambling theory.

The book had a particularly interesting and surprising discussion on the Kelly Criterion: a method of wagering that ensures the quickest maximization of bankroll when you have positive expectation in a game. Basically, if you have a probability p > 0.5, you maximize your bankroll when you wager a fraction of your bankroll equal to 2 * p – 1.

Griffin asked an interesting question: what is the probability at any step that you actually have reached the highest bankroll that you’ve ever seen in that step. When the bets are unit sized, you can derive rather simply (and prove via simulation) that the odds are 2 * p – 1 (interestingly, the same fraction used by the Kelly Criterion) that you have reached your peak earnings. But if you try to graph the resulting curve when you use proportional Kelly style bets, you get a function which is not only fairly complicated, but is in fact discontinuous. This seemed very unintuitive to me, so I wrote a simple program to duplicate the result and plotted it with gnuplot. For each probability p, I simulated one million wagers, and counted the number of times that I reached a new maximum.

Check out the graph:

The discontinuities are real, and the discussion is quite illuminating.

Addendum: The discontinuities occur because of the following. Imagine that you are at an all time high, and then suffer a loss, then a win. When you lose, your bankroll is multiplied by 1-f, and when you win it is multiplied by 1+f. Taken together, you get 1 – f², which is always less than one, so you know that after all possible sequences of length two that ends in a win (you need to minimally end with a win to reach a peak) you can’t reach a peak.

How about length three? Well, let’s try a loss followed by two wins. You have (1-f) (1+f)², which you want to be one (or higher). Solving this, we get 1 + f – f² – f³ = 1, which means f – f²-f³ = 0, or 1 – f – f² = 0. Solving using the quadratic formula, we find that f yields a value of one precisely at (sqrt (5) – 1)/2, a number commonly referred to as the golden mean or phi. Sure enough, our graph displays a discontinuity there. At just below this value, a loss followed by two wins is insufficient to generate a new high, but at just over this value, it is. Since the probability of these particular sequences varies only infinitesmally, we see a strong discontunity in the chances of reaching a new high when f varies in this neighborhood.

Other possible sequences (two losses followed by three wins, for example) also generate similar but smaller discontinuities.

Very interesting.

At least to me.

But I’m a geek.

Addendum²: For fun, try reading Kelly’s Original Paper and figure out what it says about gambling.

I just got my first issue of Make, and all I can say is Wow! Terrific magazine. Fifteen minutes after cracking it, I went to the website and subscribed, then went back and read some more. If you need food for your inner-geek-child, this is it. Don’t miss it.

Today’s book recommendation is Brad Graham and Kathy McGowan’s Build Your Own All-Terrain Robot. Brad and Kathy are the authors of a book which was highly recommended to me, Atomic Zombie’s Bicycle Builder’s Bonanza. I’m not all that interested in building strange bicycles, but robots, hey, that seems like more up my alley.

I’ve got quite a few books that concentrate on making robots which are little more than toys, but I was beginning to think of a bit grander project: a robot that could navigate outside over realistic if not rugged terrain. And this book delivers! It gives detailed descriptions of two different robotics projects, and tells you what you really need to know to get going. You won’t find chapters entitled “how to solder” or “PIC assembly code”, but you will find lots of information on finding the right motors, batteries, how to design and fabricate a welded steel frame, how to get it all working with remote control, and how to mount cameras and even a FRS radio to allow you to see what your ROV is doing.

Great book, highly recommended.

After reading some of the material on 43folders.com, I decided to order, read and apply some of the lessons in the book. It’s good! I’ll have some more comments later, but some good additional pointers are here. Try reading them to see the flavor of Allen’s approach, and to see if it might be helpful to you.

Inspired by Dave Slusher’s mention of Robert Rodriguez and his Ten Minute Film School, I decided to get a bunch of books on the subject of low budget guerilla film making. To get the total up high enough to get free shipping from Amazon, I purchased

• Rebel Without a Crew by Robert Rodriguez
• How to Make an Action Movie for $99 by Andrew Harter, and
• How to Make Your Own Damn Movie by Lloyd Kaufman

I got them mainly to absorb a bit of the low-budget bootstrap mentality that seems common among film makers. It certainly has never been more affordable for amateurs to develop powerful media, and I’m hoping that by reading them, some of their enthusiasm and knowledge will rub off on my feeble efforts.

I’ll be reviewing these in future podcasts, so stay tuned.

I must admit, I’ve been a slacker. I haven’t read Lawrence Lessig’s book Free Culture, and since you can actually get free copies of the book off the web, there really is no excuse. Indeed, today I decided to download the audiobook version to my iPod before I hit the treadmill to exercise. The audiobook is actually very cool: because the book itself is licensed under a liberal Creative Commons license, several people each read a chapter of the book and they were all merged together to produce a 9.7 hour long version of the book. Good stuff.

It really is a great book. I find Lessig to be very accessible, and he presents his thesis in a very straightforward manner. He believes (as do I) that increasingly the manner in which we create and extend our collective culture is falling under government regulation. The issue isn’t as simple as whether you are pro-piracy or pro-property rights: Lessig himself believes in intellectual property. He believes however that legislation of heretofore unregulated aspects of our culture are increasingly falling under regulatory control, and that this regulation stifles innovation, creativity, and even democracy itself.

It’s good stuff, and there is no reason not to read it.

Thorp’s book, The Mathematics of Gambling, is apparently available online with permission of the author.

Thorp is of course the author of the classic book Beat the Dealer, to which an entire generation of card counters owe their heritage.