[Link] Opacity as a defense against bias?

4 malthrin 28 December 2011 06:15PM

This article makes the claim that financial systems are opaque in order to help us overcome our risk aversion:

Opacity is not something that can be reformed away, because it is essential to banks’ economic function of mobilizing the risk-bearing capacity of people who, if fully informed, wouldn’t bear the risk. Societies that lack opaque, faintly fraudulent, financial systems fail to develop and prosper. Insufficient economic risks are taken to sustain growth and development. You can have opacity and an industrial economy, or you can have transparency and herd goats.

I don't entirely agree. There's also a risk-pooling aspect (similar to insurance) and a middleman research value-add (individuals don't have to study thousands of possible investments). Still, it's an interesting idea. What other areas of the economy could make a similar argument?


[LINK] Fermi Paradox paper touching on FAI

2 malthrin 03 December 2011 07:22PM

This paper discusses the Fermi Paradox in the context of civilizations that can build self-replicating probes (SRPs) to explore/exploit the galaxy. In passing, it discusses some FAI-related objections to self-replicating machine intelligence.

One popular argument against SRPs is presented by Sagan and Newman (Sagan and Newman, 1983). They argue that any presumably wise and cautious civilization would never develop SRPs because such machines would pose an existential risk to the original civilization. The concern is that the probes may undergo a mutation which permits and motivates them to either wipe out the homeworld or overcome any reasonable limit on their reproduction rate, in effect becoming a technological cancer that converts every last ounce of matter in the galaxy into SRPs.

Bad Clippy.

Probability puzzle

7 malthrin 28 November 2011 09:33PM

I came up with this puzzle after reading Vaniver's excellent post on the Value of Information. I enjoyed working it out over Thanksgiving and thought I'd share it with the rest of you.

 

Your friend holds up a curiously warped coin. "Let's play a game," he says. "I've tampered with this quarter. It could come up all heads, all tails, or any value in between. I want you to predict a coin flip; if you get it right, I'll pay you $1, and if you're wrong, you pay me $3."

"Absolutely, on one condition," you reply. "We repeat this bet until I decide to stop or we finish N games."

What is the minimum value of N that lets you come out ahead on average?

 

Each game, you may choose heads or tails, or to end the sequence of bets with that coin. Assume that all heads:tails ratios are equally likely for the coin.

 

edit: since a couple people have gotten it, I'll link my solution: http://pastebin.com/XsEizNFL

5 Second Level: Substituting the Question

20 malthrin 28 October 2011 12:20AM

I picked this up in the new Kahneman book, Thinking, Fast and Slow. He describes a common characteristic of reasoning heuristics: rather than answer a difficult question, they substitute a simpler question with a more readily available answer. This is a common failure mode.

Later that evening, my wife made a comment about an article she was reading on diagnosing depression. I immediately thought, "I'm pretty sure I've never been depressed." The speed of my response was a red flag. Did I really just scan the past 10 years of my adult life for depression symptoms? Or did I answer an easier question: "Am I depressed right now?" With a mouth full of delicious toast, the available answer was, "I feel great!"

I think this technique is a good fit for the 5 Second Level, though it may need a name that indicates what to do rather than what to avoid doing. Hug the Query is close, but taken. The cover blurb for the skill is: take notice when you easily and swiftly answer a question, and double-check that you actually answered it.

Here are a some more examples from the book:

  • Target question: How much would I contribute to save an endangered species?
    Heuristic question: How much emotion do I feel when I think of dying dolphins?
  • Target question: How happy are you with your life these days?
    Heuristic question: What is my mood right now?
  • Target question: How popular will the President be six months from now?
    Heuristic question: How popular is the President right now?
  • Target question: How should financial advisers who prey on the elderly be punished?
    Heuristic question: How much anger do I feel when I think of financial predators?
  • Target question: This woman is running for the primary. How far will she go in politics?
    Heuristic question: Does this woman look like a political winner?

 

HPMoR: What do you think you know?

12 malthrin 23 October 2011 04:17AM

(And somewhere in the back of his mind was a small, small note of confusion, a sense of something wrong about that story; and it should have been a part of Harry's art to notice that tiny note, but he was distracted. For it is a sad rule that whenever you are most in need of your art as a rationalist, that is when you are most likely to forget it.)

Why does the wizarding world believe Voldemort used the Killing Curse on Harry? Whether or not the Love Shield exists in MoR, I doubt most wizards had an >epsilon prior for the Killing Curse resulting in a scarred but otherwise unharmed target, a dead and burned spellcaster, and a destroyed building. There were no surviving witnesses except Baby Harry. Where did that version of events come from?

If I was Joe Random Wizard and heard that evidence without names attached, I would naively hypothesize: Dark Wizard shows up at house, encounters mother + father + their allies. Battle ensues. Parents and Dark Wizard are slain. House is destroyed and baby is hit by debris. There is one obvious question - why the allies didn't take the baby with them - but any answer to that is more plausible than "There were no allies; the most reliable curse in the world backfired on its most experienced practitioner."

Not that the "reflected curse" story was hard to sell. People are great at not asking the next question when they want to believe.

We have some additional information about the events of that evening:

  • Harry's memory under Dementation (Ch43). This may or may not be a true memory.
  • Snape relayed the complete prophecy to Voldemort without understanding it (Ch77). McGonagall was the propechy's witness (Ch28), but Snape has also heard the original audio (Ch77).
  • McGonagall knows that Voldemort is still around (Ch6).
  • Quirrellmort does not want to kill Harry. If he ever did, he changed his mind while offscreen.

What really happened at Godric's Hollow?

 

PS. If the Love Shield does exist in MoR, do you suppose Bellatrix could cast it?

 

Biases to watch out for while job hunting?

7 malthrin 21 May 2011 07:28PM

I'm in the process of searching for a new job. I'm currently employed, but I'm dissatisfied with my salary and career growth options. I've done a couple of phone interviews and one face-to-face interview already, with several others lined up next week. The face-to-face interview went well, and I'm anticipating an offer from them next week. However, while considering how I would evaluate that offer, I caught myself awarding them points in reciprocation for their implicit praise in singling me out as a worthy candidate. Now I'm wondering what other biases I might be falling prey to in this process. Thoughts?

[LINK] Human Brain Project aims to emulate brain by 2024

3 malthrin 18 May 2011 10:38PM

http://nextbigfuture.com/2011/05/henry-markram-and-human-brain-project.html

Henry Markram says the mysteries of the mind can be solved -- soon. Mental illness, memory, perception: they're made of neurons and electric signals, and he plans to find them with a supercomputer that models all the brain's 100,000,000,000,000 synapses.

Markram's TED talk:

http://www.ted.com/talks/henry_markram_supercomputing_the_brain_s_secrets.html

Elitist Jerks: A Well-Kept Garden

21 malthrin 25 April 2011 06:56PM

In response to: http://lesswrong.com/lw/c1/wellkept_gardens_die_by_pacifism/

I'm a moderator at Elitist Jerks (http://www.elitistjerks.com), a World of Warcraft discussion forum. Within the WoW community, EJ has always been known for its strict moderation standards. We're exactly the sort of 'well-kept garden' that EY's post is about. You can see the fruit of the mod team's labor here: http://elitistjerks.com/f34/ I'll give some of the site's backstory for non-WoW players, describe the crossroads that we're currently at, and then give some caveats before you generalize too much from our example.

EJ's initial community came together to discuss WoW's most challenging content, known as "raids". In order to optimally outfit our characters for maximum performance in raids, both empirical and theoretical work was necessary: the game's combat mechanics were reverse engineered and detailed models for each character class were created. Within a couple of years, this "theorycrafting" work became the forum's primary purpose - refining and updating models as new game patches were released. Throughout the forum's life, high moderation standards have been maintained in order to protect our high signal/noise discussion. Primarily, asking for help is forbidden when the resources to answer your question already exist.

However, we're starting to wonder if we've performed our task too well. 

  • Discussion about any aspect of the game that can't be quantified has almost completely died out. Despite having threads explicitly designated for more subjective topics, the overall forum atmosphere is sufficiently hostile/intimidating to non-analytic personalities that those threads don't see much traffic.
  • Further refinements in class modeling are so small as to be empirically unverifiable - their impact emerges in lengthy runs of simulated combat, but is washed out by random factors (critical hits, etc) in the 5-10 minutes of a typical raid encounter.
  • The community is heavily dependant on a few dozen key contributors who maintain the accepted spreadsheet/simulation models. By encouraging all our visitors to use their tools, we've made these people into single points of failure. When one of them quits the game, it's difficult to find another to take up maintenance on their model, because any programmer would rather write new code than work on old code (http://www.joelonsoftware.com/articles/fog0000000069.html).
  • In addition to the previous, some of the class models simply aren't as good/reliable as others. However, due to the average person's inability to shut up and multiply (http://wiki.lesswrong.com/wiki/Shut_up_and_multiply), we don't allow posts questioning model output unless they have a detailed proof of a bug. As a result, the models that should be taken with a grain of salt are treated with just as much credibility as the strongest.

So here we moderators sit on our porch, having kept our garden tidy for six years now. The questions we're asking are "Is this the community we meant to create?" and "What happens to a community formed to solve a problem once the problem is effectively solved?"

Caveats:

  • There is a private area of the forums where subjective and off-topic discussions still take place. However, these discussions are invisible to non-paying members. I personally worry that quarantining our fun may be just as dangerous for the health of the community as diluting it. This opinion is not universal among the moderation team.
  • WoW is, in the larger scope of things, not that hard a problem. What to do after accomplishing a primary goal is not likely to be a problem for a more broadly-scoped community. Even in WoW, hard problems remain that resist quantification - How do you motivate 25 people to keep battling a dragon that's been killing them for the last 2 hours? How do you identify the recruits that will best fit into an existing group and its culture? How do you balance redundancy and responsibility in leadership?

 

edit: fixed some link formatting