When seeing X suggests ‘generally ¬X’

Cross posted from Overcoming Bias. Comments there.

***

Suppose nobody has ever told you that they like you. Suppose you are relatively uncertain about how often people like other people, and also about how often they will disclose it when they do. Suppose you are confident that these facts about your ignorance and social inexperience do not bear on whether other people like you. So as it stands you are fairly uncertain about your popularity. Suppose also that you have a deep and insatiable need for people to like you, and your pleasure is roughly linear in the number of people who like you.

Suppose one day a person tells you that they like you. If you are given to expressing emotions or making inferences, one thing you might wonder is whether this should be cause for happiness.

This is not as obvious as it first seems. A person telling you that they like you is more probable if:

  1. This specific person likes you.
  2. People like you in general
  3. People are given to expressing their liking for other people

The first two are promising. The third makes the fact that nobody else has ever said they like you a bit more damning. Just how much more damning depends on your probability distribution over different possible states of affairs. For an extreme example, suppose you had even odds on two extreme cases – people always saying they like people who they like, and people never doing so – and that many people have had a chance by now to tell you if they like you. Then you should be extremely sad if anyone tells you that they like you. The apparent update in favor of people liking you in general will be completely overwhelmed by the reverse update from flatly ruling out the possibility that all those people you have already met like you.

In general, seeing an instance of X can make X less likely, by indicating that X tends to be visible:

  • Hearing your neighbors have loud sex might lower your estimate of how often they have sex.
  • Finding a maggot in your dinner might reassure you that maggots in dinners are relatively visible (this is just a hypothetical example – in fact they are not, especially if your dinner is rice)

Conversely, failing to see X can make X more likely, by increasing the probability that it is invisible:

  • If you have never observed a person lying, it might be more likely that they are an excellent and prolific liar than it would be if you had seen them lie awkwardly once. Though not once all the excellent liars realize this and stumble sheepishly over a white lie once in a while.
  • Failing to observe phone calls  from friends for too long will often cause you to suspect they have in fact been calling you, and there is rather something wrong with your phone.

Personal experimentation: summary

Cross posted from Overcoming Bias. Comments there.

***

asked how it could be that experimenting in my own life could be worthwhile, given that if such things were worthwhile other people should have already figured them all out. My suggested explanations:

  1. I am strange: nerdy, recent, young
  2. Innovation: there are constantly new things to experiment with
  3. Findings are not spread: or so much noise is also spread that the information is lost
  4. Context-specificity: your findings don’t apply to me, because people are unique or situations are complicated
  5. I am wrong: it’s easy to underestimate nebulous costs, to overstate fleeting or illusory benefits, to want to be the kind of person who tries new things, or to be too hopeful that life can improve fast

It seems to me that 3 is the biggest: results are collected so badly as to be often worthless and are aggregated poorly. It’s not clear to what extent this is because of 4: other people’s findings are just not so useful. Personal experimentation seems worth it even without good aggregation, but probably only if you avoid the same errors of measurement yourself. It could be worth it even with purely placebo gains, if you enjoy the placebo gains enough. But in this scenario, the gains are much smaller than you imagine, so you are probably over-investing a lot. There also seems to me a real risk that everything is so context specific that what you learn will be worthless as soon as you change many other things (4).

Explanations that involve others finding experimentation a lot less worthwhile (e.g. 1) seem unlikely to help much because it looks like others often find experimentation worthwhile. The problem seems to be somewhere between others making such efforts, and me having useful information as a result. Innovation (2) seems a bad explanation because it doesn’t explain the lack of information about age-old lifestyle questions. It seems likely that I have overestimated gains relative to losses in the past (5), but gains still seem larger than losses (it’s hard to disentangle causes, but my lifestyle has obviously improved substantially over the last  year or more, some of which seems directly attributable to purposeful experimentation and the rest of which seems at least not terribly damaged by it).

What motivates cognition?

Cross posted from Overcoming Bias. Comments there.

***

When I was a teenager, I think I engaged in a lot of motivated cognition. At least in an absolute sense; I don’t know how much is common. Much was regarding trees. Before I thought about this in detail, I assumed that how motivated cognition mostly works is this: I wanted to believe X, and so believed X regardless of the evidence. I looked for reasons to justify my fixed beliefs, while turning a blind eye to this dubious behavior.

On closer in(tro)spection, this is what I think really happened. I felt strongly that X was true because many good and smart adults had told me so. I also explicitly believed I should believe whatever my reasoning told me. I was inclined to change my beliefs when the information changed. However I knew that I did this, I feared that my reasoning was fallible, and I was terrified that I would come to believe not-X even though X was the truth. Then the truth would come out, or more evidence at least (and obviously the truth would be X), then all the good people who knew X would consider me evil, which was equivalent to being evil. They would also consider me stupid, for not seeing the proper counterarguments. So it was sickening to not be able to come up with a counterargument, because such a failure would immediately turn me into an evil and stupid person. Needless to say, I was quite an expert, especially on counterarguments.

So unlike in my usual model of motivated cognition, my arguments were directed at persuading myself of things I feared doubting, rather than justifying fixed beliefs to others. How often is this really what’s going on?

Personal experimentation: I’m wrong?

Cross posted from Overcoming Bias. Comments there.

***

I’ve been wondering why experimentation seems worthwhile. I’ve given some explanations in my last few posts. The last category of explanations to consider are the ones in which my judgement is wrong. Where experimentation seems worth it because I don’t see the costs, or because I overestimate the benefits.

A lot of the cost from experimentation is plausibly nebulous and hard to account for well in a simple explicit analysis. Life can’t run smoothly on habits when they are always in flux. Mental effort is used up in keeping track. Every new thing takes a little while to do well, and to integrate into your lifestyle.

It’s easy count the costs of living in Oxford for a month in airfares and flight times, and forget the freezing afternoon you might spend negotiating to reclaim your foreign credit card from an ATM that ate it. Or the hassle of urgently buying boots, or of running up the high street looking for a working internet connection to finish your Skype call, or the sleep loss due to alien fire alarm policies at the college where you are staying. It seems to me that I have tended to underestimate such costs in the past substantially.

I mentioned in earlier posts some reasons I might overestimate the benefits. Innovation is less worth finding if it is quickly obsoleted by context specificity or further innovation. Informal data collection seems to see benefits too easily in every change. Nerds may underestimate the wisdom embodied in tradition. The first of these seems unlikely, given my experience. The others seem dangerous, but I do guard against them.

One might also overestimate the benefits if one is motivated to do so. Being willing to try new things is a telling sign about a person, or often taken to be one. Often it is a sign you should want to send. This hypothesis is supported in my case by the observation that many people I know seem to find experimentation particularly useful. However I rarely talk about this kind of stuff, and feel a bit silly when I do. Which doesn’t fit a signaling hypothesis well. Though this blog sequence undermines my claims some.

One might also be biased by other motivations. For instance if you badly hope that life can get much better, it might be hard to accept a route to that which involves sitting by and waiting when there are so many ways to aggressively search. I admit I would probably have some trouble accepting that this is as good as it gets, but I think I would at least be aware of discomfort around the topic if this was what was going on. So this seems unlikely to account for the observation.

To me underestimating the hidden costs seems by far the biggest danger.

Personal experimentation: context specific?

Cross posted from Overcoming Bias. Comments there.

***

A last way that personal experimentation could be worth it for me, yet not already completely covered by others, is that most of the facts one is likely to learn are quite context-specific. That way, everyone in history might have figured out for themselves what the best time and sugar-content for lunch is, and it would be worthless to me.

This also seems quite plausible. It could either be that people are so varied that there is just no good answer to whether it is better for productivity to eat snacks throughout the day or a few big meals for instance. Or it could be that which value of one parameter is best depends on all the other ones, so if you tend to eat more sugar than me and sleep less and laugh more, exercise might make you less sleepy than I.

The latter possibility bodes poorly for those who would experiment a lot. After you have determined the best quantity and timing of exercise, you might go on to try to optimize your sleep or sugar intake and make the original finding worthless.

This explanation would also seem to explain the observations in the last post: that many people do seem quite keen advise on the details of one’s life, but that the content of such recommendations seem a bit all over the place. Perhaps each person’s discoveries really do work well for them, but just look like a sea of noise to all the other people.