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All of etymologik's Comments + Replies

Welcome to Less Wrong! (9th thread, May 2016)
etymologik
20

Thanks much for the link to the Secretary Problem solution. That's will serve perfectly. Even if I don't know the total number of houses that will be candidates for serious consideration, I do know there's an average, which is (IIRC) six houses visited before a purchase.

As for cheating ... what I mean by that is deluding myself about some aspects of the property I'm looking at so that I believe "this is the one" and make an offer just to stop the emotional turmoil of changing homes and spending a zillion dollars that I don't happen to possess. &... (read more)

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2Lumifer
In some areas that's not terrible. The thing is, if you're building a bridge you want that bridge to not fall down and that will or will not happen regardless of your illusions, delusions, and sense of accomplishment. However if you're picking something to make you happy, this no longer applies. Now your perception matters. Let's say you are looking at a house that checks off all the checkboxes, but on a instinctual, irrational level you just hate it. Maybe there's something about the proportions, maybe there's some barely noticeable smell, maybe there's nothing at all you can articulate, but your gut is very clearly telling you NO. Do not buy this house. The reverse (your gut is telling you YES) is iffier for reasons you're well aware of. However my point is still valid -- when doing or buying things (at least partially) for the experience they will give you, you need to accommodate your perceptions and self-delusions, if only because they play a role in keeping you happy. Um, not sure about that. See, you can assess anything you want but you still need a buyer. You still need someone to come and say "This is what I will part with all my savings and get into debt for". No one obligates you to buy a house which is priced "fairly" on comparables but does not satisfy you. Markets are generally quite good at sorting these things out and the real estate market is not sufficiently screwed up to break this, I think.
0gjm
Beware! The optimal solution depends a lot on the exact problem statement. The goal in the SP is to maximize the probability that you end up with the best available option, and it assumes you're perfectly indifferent between that and all other possible outcomes. That Wikipedia page discusses one variant, where each candidate has a score chosen uniformly at random between 0 and 1, and all you learn about each candidate is whether it's the best so far. Your goal is to maximize your score. With that modification, the optimal strategy turns out to be to switch from "observe" to "accept next best-so-far" much sooner than with the original SP -- after about sqrt(n) candidates. Your actual situation when buying a house is quite different from either of these. You might want to hack up a little computer program that simulates a toy version of the house-buying process, and experiment with strategies.
Welcome to Less Wrong! (9th thread, May 2016)
etymologik
00

In the home purchase decision use case, I'm currently working with a "utility table" where the columns list serious home purchase candidates, and one column is reserved for my current home as a baseline. (The theory there is I know what my current home feels like, so I can map abstract attribute scores to a tangible example. Also, if a candidate new home fails to score better overall than my current home, there's no sense in moving.)

The rows in the utility table list various functions or services that a home with its land might perform and vario... (read more)

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0Lumifer
What do you mean "cheat"? Presumably you want to buy a house you like, not just the one that checks the most boxes in a spreadsheet. That doesn't look like a reasonable procedure to me. So whether a house has exterior steps gets to be as important as the price? One of the reasons such utility tables have limited utility is precisely the weights. They are hard to specify but naive approaches like making everything equal-weighted don't look to lead to good outcomes. Effectively you need to figure out the trade-offs involved (e.g. "am I willing to pay $20K more for a bigger yard? How about $40K?") and equal weights for ranks are rather unhelpful. I agree that making a list of things you need and value in a house is a very useful exercise. But you can't get to the level of completeness needed to make the whole thing work the way you want it to work. You mention updating this table on the basis of your perceptions and experience, but if your ranks are equal-weighted anyway, what do you update? With respect to the houses serially appearing before you, a simplified abstraction of this problem has an optimal solution.
Welcome to Less Wrong! (9th thread, May 2016)
etymologik
00

Thanks for that explanation of utility functions, gjm, and thanks to protostar for asking the question. I've been struggling with the same issue, and nothing I've read seems to hold up when I try to apply it to a concrete use case.

What do you think about trying to build a utility TABLE for major, point-in-time life decisions, though, like buying a home or choosing a spouse?

P.S. I'd upvote your response to protostar, but I can't seem to make that happen.

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3gjm
I'm not sure exactly what you mean by a utility table, but here is an example of one LWer doing something a bit like a net utility calculation to decide between two houses. One piece of advice I've seen in several places is that when you have a big and difficult decision to make you should write down your leading options and the major advantages and disadvantages of each. How much further gain (if any) there is from quantifying them and actually doing calculations, I don't know; my gut says probably usually not much, but my gut is often wrong.
8gjm
You need, I think, 10 points before you're allowed to upvote or downvote anything. The intention is to make it a little harder to make fake accounts and upvote your own posts or downvote your enemies'. (Unfortunately it hasn't made it hard enough to stop the disgruntled user who's downvoting almost everything I -- and a few other people -- post, sometimes multiple times with lots of sockpuppet accounts.)
0Lumifer
The words "utility function" here are usually used in two quite different meanings. In meaning 1 they are specific and refer to the VNM utility function which gjm talked about. However, as he correctly mentioned, "humans certainly don't behave exactly as if we have utility functions, at least not sensible ones". Note: specifically VNM utility functions. In meaning 2 these words are non-specific and refer to an abstract concept of that what you would want and would choose if given the opportunity. For example if you want to talk about incentives but do not care about what precisely would incentivise an agent, you might abstract his actual desires out of the picture and talk about his utility in general. This utility is not the VNM utility. It's just a convenient placeholder, a variable that we (usually) do not need the value of. That's because humans don't have VNM utility functions and even if they did, you wouldn't be able to calculate your own on the fly. What would it look like?
The Best Textbooks on Every Subject
etymologik
10

I would also like to recommend two superb encyclopedia-style works on linguistics:

(1) "The Cambridge Encyclopedia of Language", by David Crystal

(2) "The Cambridge Encyclopedia of the English Language," by David Crystal

Both are characterized by lot of short articles, sidebars, pictures, cartoons, and examples of texts to the point at hand. I read them both cover to cover, and have refered to them again and again when beginning to explore a new topic in the field.

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The Best Textbooks on Every Subject
etymologik
40

Recommended for LINGUISTICS: "Contemporary Linguistics", by William O'Grady, John Archibald, Mark Aronoff, & Janie Rees-Miller. Truly comprehensive, addressing ALL the areas of interesting work in linguistics -- phonetics, phonology, morphology, syntax, semantics, historical linguistics, comparative linguistics & language universals, sign languages, language acquisition and development, second language acquisition, psycholinguistics, neurolinguistics, sociolinguistics & discourse analysis, written vs spoken language, animal communicat... (read more)

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9Rafael T dos Santos
I appreciate your recommendation, it's been useful to me. However, I should point this out: I'm currently researching on second language acquisition, and the section dedicated to that does not even mention the main authors in the field. There are some very, very important hypotheses being tested and debated in the last decades, as Stephen Krashen's, which are not mentioned at all. Oh, maybe this is not the case anymore: I only had access to the 1996 edition. I just saw a 2017 one in Amazon. It would be good if anybody could review the latest version, at least in the SLA section, where I found this problem.
1etymologik
I would also like to recommend two superb encyclopedia-style works on linguistics: (1) "The Cambridge Encyclopedia of Language", by David Crystal (2) "The Cambridge Encyclopedia of the English Language," by David Crystal Both are characterized by lot of short articles, sidebars, pictures, cartoons, and examples of texts to the point at hand. I read them both cover to cover, and have refered to them again and again when beginning to explore a new topic in the field.
2[anonymous]
I would also like to recommend two superb encyclopedia-style works on linguistics: (1) "The Cambridge Encyclopedia of Language", by David Crystal (2) "The Cambridge Encyclopedia of the English Language," by David Crystal Both are characterized by lot of short articles, sidebars, pictures, cartoons, and examples of texts to the point at hand. I read them both cover to cover, and have refered to them again and again when beginning to explore a new topic in the field.