All of saph's Comments + Replies

I am not sure, whether we actually have a disagreement here. Spaced repetition is a special facet of the idea that I outline in this article and I am currently experimenting with it exactly for the reason to test my "theory" above.

So what would be your other example of halo effect?

I haven't said that I have other examples of the halo effect, but examples of other biases which can also be explained by properties of how the brain processes sense inputs.

Ahh. Well i think you can explain a great deal of biases by the brain simply not being all that powerful and how it has to rely on various simple strategies rather than direct foresight and maximization of some foreseen quantity. You can't really expect a person who can't do monty hall problem, to do proper probabilities - and that's the majority of people - and then, you can't expect a person who can do monty hall problem, not to pick up various cognitive and behavioural habits from those who can't. Then, why people can't do monty hall correctly, is it some universal failure in the brain organization? Well, smart individual would figure it out, most individuals can be taught methods for figuring it out.

This is the flip side of the arguments I think you're alluding to, that the faulty thinking was actually beneficial in the EEA.

Yes. Some people I know, observe fact X about human behaviour and then conclude that it had to be beneficial for survival, for otherwise evolution would have eradicated X.

I do think we're getting sidetracked by your halo effect example, though -- it might be useful to give three or four examples to avoid this (although if each one has a different explanation, that might substantially increase the effort of presenting your i

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I think you are right that there don't have to be collisions (in practice) if the representation space is big enough and has sufficient high dimension. On the other hand there is a metric aspect involved in the way the brain maps its data, which is not present in hash code (as far as I know). This reduces the effective dimension of the brain dramatically and I would guess that it is nowhere near 128 (as in your hash example) for the properties 'good looking', 'honest', etc. It would be an interesting research project to find out.

I think that the cultural ... (read more)

Well, the beauty is positive quality for men who believe prettier women are stupider. One need to be careful not to start redefining positive qualities as those that correlate positively with each other. So what would be your other example of halo effect? USA tends to elect taller people for presidents, yet I don't think many have trouble with concept that extreme tallness correlates negatively with health. I can't really think of much halo effects, apart from other effects like e.g. if you pick someone based on one quality you rationalize other qualities as good, or if you are portraying other people you'll portray those you dislike as all around negative and those you like as all around positive (which will bias anyone who's relying on this to infer correlations). I think the bigger issue is when we prepare problems for effective reasoning. Every number should be a statistical distribution of it's possible values, yet it's very unwieldy to compute and we assign a definite number, or normal distribution. That is usually harmless but can result in gross error. There's whole spectra of colours, but nearby colours are confused, and there's artificial gradation of colours into bins. That kind of thing.

I am still reading through the older posts on LW and haven't seen CDT ot TDT yet (or haven't recognized it), but when I do, I will reread your comment and will hopefully understand how the second part of the comment is connected to the first...

This is the LW decision theory portal. If you're reading through Eliezer's sequences I don't think there's much discussion about the foundations of decision theory there.

Thanks for the feedback!

The reference to linear algebra should only show, that there have to be states which are mapped to similar representations, even if we don't know a priory which ones will be correlated.

But if we now look closer at the structure of the brain as a neural network and the learning mechanisms involved, then I think that we could expect positive concepts to be correlated by cross activation, as you explained.

The point of the article is not to come up with a perfect explanation for how the halo effect is actually caused, but to show that there doesn't have to be an evolutionary reason for it to evolve, besides the 'obvious' one that pwno mentions in his comment.

Yes. I thought you were making an interesting and useful point. I was offering you an alternate formalism to explain the phenomenon, not expressing a disagreement with anything you wrote.

And letters are nothing more than ink. How can consciousness arise from mere neurons ? The same way that the meaning of a text can arise from mere letters.

I am not sure if this is a good analogy. The meaning of text is usually not hidden somewhere in the letters. Most of it is in the brain of the writer/reader. (But I agree that some meaning can be read out from a text without much previous knowledge.)

Quoting kilobug: From what I understood these analogies are meant to better explain some basic point to people with little to no previous background. I assume that the average target of these analogies has never quite considered your objection, and is sitting on a lower level, so the analogy should be good enough to deliver the point. Once you've made yourself clear, you can then explain to your interlocutor that the analogy is not an isomorphism. This is at least how I usually proceed when trying to explain new and complicated concepts to people that encounter them for the first time.

While I agree with your comment, I have an observation to make. While driving a car, I found it quite useful to consider the car as an extended part of my body. The same is true for spoons, knives and forks while eating.

It's pretty mush how the brain treats any proper tool use. In fact, at the present moment I sort of consider the entire internet, including your brain, as part of my extended body. :p There was this great set of experiments I read about long ago and vaguely remember. There was one with two rubber staffs you held crossed and one with a rubber hand someone hit with a hammer and one where you used VR visors to look through a camera behind your back and some stuff like that. There is an IMMENSE flexibility in what senses and objects the human brain can include in it's self image. Really fascinating area, love this kind of thing.
Also why you don't touch people's wheelchairs.


  • Handle: saph
  • Location: Germany (hope my English is not too bad for LW...)
  • Birth: 1983
  • Occupation: mathematician

I was thinking quite a lot for myself about topics like

  • understanding and mind models
  • quantitative arguments
  • scientific method and experiments
  • etc...

and after discovering LW some days ago I have tried to compare my "results" to the posts here. It was interesting to see that many ideas I had so far were also "discovered" by other people but I was also a little bit proud that I have got so far on my own. Probably this... (read more)