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High Frequency Trading and Finance's Race To Irrelevance

TerranFury Re:The title of my next stock market guide (382 comments)

It could even work... (For some other authors, perhaps it already has...)

(Oh -- and, off topic; I saw your signature -- respect for finishing a novel. That's cool.)

about 2 months ago

High Frequency Trading and Finance's Race To Irrelevance

TerranFury Re:The title of my next stock market guide (382 comments)

I can't tell if these are arbitrarily chosen symbols meant to be a joke ("everybody is looking for an easy algorithm to get rich and there is none"), or an esoteric reference ("there is a standard formula used in finance, called..."), or maybe an idea you began to play with on your own... Are you being serious?

I ask because it looks almost like a dynamic programming solution to some problem -- like your "F" is a Q-table or Bellman Value Function, and "d" is some instantaneous cost.... although I'd expect inequalities, not equalities... unless S(Ai,Bj) and d are slack variables(?).... and S even suggests "slack" -- but what are Ai, Bi?

Your symbols are on the verge of making sense to me... Is this just pareidolia? Have I just had too much coffee? Or is there actually some (optimal control?) problem you're hinting at?

about 2 months ago

High Frequency Trading and Finance's Race To Irrelevance

TerranFury Re:Technological solution (382 comments)

But you can always trade contracts, outside that market (and unclocked/asynchronously), for shares in it, at which point it's the price of those contracts that you need to look at, I would think. Or in other words, if you make certain kinds of financial transactions "illegal" (i.e., asynchronous/"unclocked" ones), the demand for those transactions is filled by another, "black" market (i.e., the one where contracts are bought and sold). Or in yet other language, you can build the old, asynchronous, abstraction, on top of the new, synchronous one, by adding a "side channel" of asynchronous information.

(I assume "real" econ./finance people have words for all of this.)

about 2 months ago

Should the US Copy Switzerland and Consider a 'Maximum Wage' Ratio?

TerranFury Re:Mathematical explanation (1216 comments)

I really like this post. I have been playing with (or -- threatening to play with) a nearly identical model myself. There are a number of things to prove about this Markov chain, including what the stationary distribution is.

One additional effect to consider would be something like a "blur kernel," which could describe the flow of wealth within the economy to "nearby" individuals (e.g., the coffee shops in the finance district might be able to charge more, and so wealth will tend to diffuse to them). I think that effects like this are, at least in theory, what are supposed to prevent the excessive concentration of capital. Modeled on a graph, one could ask questions like, "How does income inequality (e.g., Gini coefficient) change as a function of graph connectivity (e.g., Fiedler number)?" The obvious story then would be that, as the economy becomes increasingly centralized in a topological sense (with some appropriate graph-theoretic measure of centralization), or as people become less dependent on commerce with their peers, distributions sharpen and inequality grows.

Finally, I'll add that there are other models of social phenomena, like armed conflict, with similar "inequality exacerbating" properties; see e.g. Lanchester's square law of combat. In fact, I think RTS games like Starcraft are an interesting model for this kind of thing -- they're really-abstracted models of violent societies -- and, between Lanchester's square law, and the exponential growth of the economy (the rate at which you can build SCVs is the rate at which you can mine minerals is the rate at which you can build SCVs...), you see the same kind of positive feedback there. Of course, I don't think you need a full-on video game to demonstrate this; the old board game Monopoly was invented by a Quaker woman to exhibit the same property and so demonstrate the evils of capitalism (...and everyone missed the point). In short, I think it's easy, and interesting, to construct mathematical systems that broadly have these properties.

Of course, to turn this kind of mathematical play into something with actual predictive power -- to do science -- would be a whole 'nother undertaking.

about 8 months ago

Should the US Copy Switzerland and Consider a 'Maximum Wage' Ratio?

TerranFury Re:Ratio (1216 comments)

At the end of a year, there's going to be a bell curve of results.

If people's net worths were iid Gaussians, all those "amount of wealth in the bracket vs. center of bracket" plots you see floating around to demonstrate wealth inequality (e.g., this one) would be erfinv curves. But you see, they're not.

Now, I get that we can take some liberties with the language and call various distributions besides Gaussians "bell curves." One model, which arises from reasonable-enough assumptions, would be a Boltzmann distribution -- and, indeed, for incomes under about $250k in the US, the distribution does match the Boltzmann pretty well. So, within that broad swathe of incomes, maybe you can make an argument that there's just always going to be a certain amount of random variability.

But those aren't the income ranges people are talking about. People are talking about a systematic movement of wealth, which requires more explanation.

about 8 months ago

Obama Praises Amazon At One of Its Controversial Warehouses

TerranFury Re:doctors & lawyers, you're next... (435 comments)

Everyone talks like this: "You spend too much on little luxuries; you should not be enjoying these things; there is a moral value to going without them; and you will be rewarded in the economy for your asceticism."

But here's the thing: Those little luxuries are absolutely negligible expenses. You could buy a $5 latte every day for under $2k a year.

For comparison:
- College for one child (4 yrs) can be expected to cost $250k.
- A one-bedroom condo costs $500k.
- A 20-year retirement at $50k/yr costs $1M

Those numbers may sound large, but they really are accurate for desirable metro areas. And you will have to work for each one of those dollars, because at this point, any assumption that investment appreciation will outpace inflation is just wishful thinking (outside of property, whose very appreciation is placing it increasingly out-of-reach).

Next to the sheer magnitude of those costs, what's $5?

about a year ago

Why Engineering Freshmen Should Take Humanities Courses

TerranFury Re:Humanities can't explain the need for humanitie (564 comments)

The case for the humanities is easy:

  1. Science is about how the physical world works.
  2. Engineering is about how to get the physical world to do what you want.
  3. The humanities are about deciding what you want in the first place.

A metaphor

Say life is about finding the shortest path through a graph. Science tells you what the edges of the graph are -- what nodes are connected to what other nodes. Engineering gives you a shortest-path algorithm (say, Dijkstra's). The humanities tell you what node to find the shortest path to

. A control-theoretic perspective:

More generally, the world has a state x(t), and science gives us the transition model -- the function f such that,

dx/dt = f(x,u)

where u(t) is our control input to the world at time t. This is Newton's Theory of Universal Gravitation, or Einstein's Theory of General Relativity, or whatever.

Engineering is about the following problem: Given a functional V that takes a state trajectory and returns a cost for that trajectory (this summarizes our opinion about what we want and what we do not want), solve (or approximately solve) the following optimization problem:

minu V(x) s.t. dx/dt = f(x,u) x(0) = x0

In other words: Having decided what I want (V), and having figured out how the universe will react to my actions (f), figure out how to make the universe do what I want.

The humanities are about deciding what functional V to use. Science can't give it to you: It's an input to this whole thing.

The above formulation can be tweaked a little -- for instance, there is no uncertainty involved -- but it captures the gist of things.

about a year ago

Cyber Vulnerabilities Found In Navy's Newest Warship

TerranFury Re:What a name. (162 comments)


Good Ship Names:

  • U.S.S. Dauntless
  • U.S.S. Enterprise
  • H.M.S. Indefatigable
  • H.M.S. Indomitable
  • H.M.S. Implacable
  • U.S.S. Intrepid

Bad Ship Names:

  1. U.S.S. Freedom
  2. U.S.S. George H. W. Bush
  3. H.M.S. Unicorn

Ship Names Too Excellent to Use:

  1. G.S.V. Eschatologist

about a year ago

How much I care about GMO food labeling:

TerranFury Re:No, it's not bullshit. (461 comments)

I would agree that "GMO" is too broad a label -- but if anything, this is an argument for more labeling, rather than less.

Let's look at established food technology. It would not be helpful to simply list "WARNING: Contains synthetic ingredients" on packaging. Nevertheless, this does not stop us from requiring producers to clearly label what is in the food, in the form of an ingredients list. We do this despite the possible "public confusion" that could be caused by the fact that most people do not know what, e.g., "sodium benzoate" is.

If we are now putting other new ingredients in our food -- at the genetic level -- then it would seem that these changes should also simply be listed, with a little more specificity than, "WARNING: GMO," in the ingredients list. E.g., don't just list "corn;" list "corn (Monsanto RoundupReady (TM) strain 2.09387)."

about a year ago

How much I care about GMO food labeling:

TerranFury Yes -- and suspected in bee colony collapse (461 comments)

There is also a suspicion now that sublethal effects of glyphosate (Roundup) are making bee colonies susceptible to infection by other pathogens, and that this "one-two punch" is what's causing colony collapse. I wouldn't want to risk something essential -- pollinators -- just to get marginal boosts to yield.

about a year ago

Ask Slashdot: Is the Bar Being Lowered At Universities?

TerranFury Re:...Back in the day (605 comments)

Wait, did they [write well]? Do you have metrics to show it?

I can't generalize, but I believe that my own writing was better in high school and early college than it is now. Whenever I stumble across one of my old essays I am amazed.

After nine years of engineering school, those skills rust over.

I am also frequently amazed by books from a generation or two ago. Compared to the stream of articles I typically read, they're a breath of fresh air.

On the other hand, when I pick up old video games that I remember being hard, I beat them easily, even though I haven't touched them -- for whatever that's worth.

The mind changes.

Does the world really need [good writing] from them?

The world? I don't know. Their boss will ask for Powerpoint slides.

about a year and a half ago

Russian Space Industry To Receive $69 Billion Through 2020

TerranFury Read it wrong... (64 comments)

At first, instead of "billion," I read "bitcoin."

I was surprised, to say the least.

about a year and a half ago

What tech would you un-invent?

TerranFury Re:un-invent, please! (572 comments)

My understanding is that a need for gold (to use as currency) was a major reason for the Roman invasions first of Gaul (recent finds show pre-Roman Celts had significant gold-mining operations) and then of Dacia (now Romania). We can say with more certainty that gold was a major motive of the Spanish conquest of the New World.

The mechanism by which commodity-backed currencies motivate wars looks pretty straightforward: If your economy grinds to a screeching halt and you want to do "quantitative easing," you need to physically go out and grab more of the commodity. Fiat currencies avoid at least this issue -- and your argument about them being useful for funding wars seems to apply just as well to funding any other activity.

(It's also worth noting that, if you do have a gold or a gold-backed currency, and you do succeed in grabbing a bunch of coin from your neighbors, then, despite being commodity-backed, you will still have inflation. Apparently this is what happened in the Spanish empire as a result of all that New World gold.)

about 2 years ago

Arctic Sea Ice Hits Record Low

TerranFury Re:Its Happening (370 comments)

Ah, good. Thanks.

about 2 years ago

Arctic Sea Ice Hits Record Low

TerranFury Re:Its Happening (370 comments)

I just ran these numbers to see what they would say. I assumed the upper bound would be absurdly high. If I have not made a mistake, the bound is actually disturbingly close:

A bit of googling tells me that, in a year, the sun puts out 150 EJ.

It is said that people should consume 2000 kCal/day = 3.05 GJ

To get an upper bound on the number of people that can be supported, we take the ratio, to get 4.92e10.

The current world population is 7e9. This is 1/7-th the upper bound.

The doubling time for the world's population, at current growth rates, is (after some more googling), 54 years. That means that it will increase by a factor of 8 -- more than can be supported -- in just 162 years. More precisely, it will increase by a factor of 7 in 152 years.

That's about two human lifetimes.

Either (1) my numbers are wrong, (2) I made an arithmetic mistake, (3) growth will level off very soon, (4) we will learn to practice space agricuture at a massive scale in an implausibly-short timeframe, or (5) we're in for some pain.

about 2 years ago

Innocent Or Not, the NSA Is Watching You

TerranFury Re:Conflicted (410 comments)

A number of northern European countries -- Sweden, Denmark, Norway, Finland -- provide state health care and pensions, but also respect individual liberties to an extent sometimes even beyond in the United States.

Denmark is #3 in the World Audit Civil Liberties rankings.
Finland is #1
Sweden is #2
Norway is #5
The United States is #15.
See here.

These are the classic "Third Way" democracies -- and they outnumber the Stalinist states (USSR, North Korea, Cuba) that are always put up as straw men. In short: Your argument sounds compelling, but, like Aristotle's reasonable-sounding assertion that heaver objects accelerate faster in freefall, it is not supported by empiricism.

more than 2 years ago

Ask Slashdot: Is a Home Drone Feasible?

TerranFury Re:Short Answer: No (274 comments)

If I'm not mistaken, your basic iPhone has most of this built in. It's aware of its orientation and location, and it has a camera. Speed could be dealt with in a variety of simple ways, and avoidance problems minimized.

One of my labmates did exactly this, on Android, for a project involving (IIRC) the Air Force (He flew the resulting drone at a nearby airbase, at least). The thing worked; he controlled it by sending text messages.

more than 2 years ago

Millions In China Live In Energy Efficient Caves

TerranFury Re:arable land (210 comments)

It makes more sense to put more people on smaller land (do away with yards altogether) for energy efficiency/cost reasons than to have millions of sub-acre semiproductive farms.

Along the same lines: Why give 100 people each tiny yards, when they can have nice apartments next to a large park instead? I think the New Urbanists have it right.

more than 2 years ago

No Pardon For Turing

TerranFury Re:I have to agree (728 comments)

It's a lack of belief system.

That sounds more like (philosophical) skepticism to me. ;-)

more than 2 years ago

No Pardon For Turing

TerranFury Group identity. (728 comments)

I don't know, or care, whether atheism "is a religion." In fact, I don't even know what that sentence means.

What I do know is that, like the religions, it is becoming a group identity -- an "-ism" -- as evidenced by the extremely defensive posts being made here. If it were just a collection of ideas relating to abstractions, if people didn't identify with those ideas, if people didn't see attacks on those ideas as attacks on themselves, then nobody would care enough to get angry.

Maybe that's ok. Maybe it's useful. Maybe, most atheists grew up in staunchly religious communities, and the politics of group identity, of belonging to an oppressed minority, are helpful to resist a more generally destructive culture of religious bigotry.

But for those of us who were lucky enough to grow up in a secular environment, it gets annoying. Me? I don't need to "fight back." I'm not so afraid of the concept of God that I need to destroy it. It's an abstraction. Asking whether it exists is meaningless. Do the integers exist? Mu. I like Spinoza. I'm cool with panpsychism (what makes your unfalsifiable worldview better than mine? Maybe contemplating my part in Infinity alters my outlook.). We can flirt with ideas without marrying them. Unitarian Universalists? Sometimes too New-Agey for my tastes (For me, "energy" is measured in Joules), but I think the basic idea is the right one. Jesus of Nazareth? He did say things worth hearing. The Beatitudes? The Golden Rule? I don't need to accept Old-Testament jingoism, or Paul's sexual issues, or the dogma of a politicized medieval Church, or the divinity of Christ, to recognize that they stand on their own merits (and probably predate Jesus, which is OK).

The other day, I saw a car, with two bumper stickers. One was the common "CoEXiSt" sticker. The other was a shot at Christians. They're at odds, no? Get along, I say.

more than 2 years ago


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