# 28

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A current article in Science reports on this study about how good people are at predicting what their future selves will be like. Not very good, apparently. Daniel Gilbert, a psychologist at Harvard, with other colleagues conducted several experiments online, in which 19,000 people were asked about such things as personality traits, preferences in music, etc., answering about the present, about themselves 10 years earlier, and about what they expected 10 years hence. More precisely, this not being a longitudinal study, people of any age X predicted less difference with their X+10 selves than people of age X+10 recollected of themselves at age X. The effect did not go away with increasing age: 58-year-olds still expected less change in the next 10 years than 68-year-olds reported in the last ten.

Gilbert and colleagues call this effect "the end of history illusion," because it suggests that people believe, consciously or not, that the present marks the point at which they've finally stopped changing.

"What these data suggest, and what scads of other data from our lab and others suggest, is that people really aren't very good at knowing who they're going to be and hence what they're going to want a decade from now," Gilbert says.

Someone suggests an alternative explanation:

Another possibility is that people "might well anticipate substantial change, yet not know how they would change, and thus, just predict the status quo"

An actionable moral:

"The single best way to make predictions about what you're going to want in the future isn't to imagine yourself in the future, … it's to look at other people who are in the very future you're imagining," [Gilbert] says.

New Comment

Original study. Can we have a convention that everyone link to these directly in the main post, please?

We do, we just ALSO currently have the convention that someone else finds the link and posts it in a comment first.

Another possibility is that people "might well anticipate substantial change, yet not know how they would change, and thus, just predict the status quo"

To give a specific example: If personality can be modeled over time as a martingale)—meaning that the expected future personality is always equal to the current personality—then it is quite appropriate for participants to provide their current personality as a prediction of their future personality, even if they think that the standard deviation of the martingale is large.

More generally, given the current personality $c$ and random variable $p$ following the distribution of predicted future personality, the predicted change in personality can be characterized by the expected absolute deviation $\\operatorname E\(|c\-p|\$) or the expected squared deviation $\\operatorname E\(\(c\-p\$%5E2)). However, study 1 in the paper measured the absolute expected deviation $|c\-\\operatorname E\(p\$%7C) instead, which is a poor measure. (This limitation of the study is understandable because collecting data on $c$ and $\\operatorname E\(p\$) is relatively easy.)

The authors tried to circumvent this limitation in a replication of study 1 by asking each participant to directly predict change rather than inferring predicted change from $c$ and $\\operatorname E\(p\$). P. 97 column 2:

Instead of being asked to report or predict their specific personality traits, these participants were simply asked to report how much they felt they had “changed as a person over the last 10 years” and how much they thought they would “change as a person over the next 10 years.”

I think there is an interpretational issue here—we cannot be sure if the participants actually estimated something similar to the expected absolute deviation $\\operatorname E\(|c\-p|\$). If the participants relied on imagining a future self, then this will again give the absolute expected deviation $|c\-\\operatorname E\(p\$%7C).

I'm surprised that the authors did not report whether any of the Big Five personality domains mediated this "end of history illusion". That seems like an obvious thing to check. Maybe they're saving that for a later paper.

"The single best way to make predictions about what you're going to want in the future isn't to imagine yourself in the future, … it's to look at other people who are in the very future you're imagining," [Gilbert] says.

In other words, take the outside view.

The distinction you highlight between the expected absolute deviation and the absolute expected deviation seems extremely important; Jordan Ellenberg says that the study is measuring one and calling it the other, and goes on to say (emphasis added)

Let me be clear: I don’t think the authors are trying to put one over. This is a mistake — a somewhat subtle mistake, but a bad mistake, and one which kills a big chunk of the paper. Science should not have accepted the article in its current form, and the authors should withdraw it, revise it, and resubmit it.

Thanks for the link. Ellenberg gives a great analogy to stock prices and points out something important: the study measured the absolute expected deviation $|c \- \\operatorname E\(p\$|) for the predictors, but measured the expected absolute deviation $\\operatorname E\(|c\-p|\$) for the reporters.

This difference can explain the observed discrepancy between the two groups without invoking the "end of history illusion" because $\\operatorname E\(|c\-p|\$%20%3E%20|c%20-%20\operatorname%20E(p)|).

This difference came about because obtaining an X+10-year-old's report of current personality is equivalent to drawing a random sample from an X-year-old's distribution of actual future personality, but the X-year-olds' are providing point-estimates (of something like the mean) from their distributions of predicted future personality.

There is a curious disparity between the ardor with which we tackle the issue of defending against being reprogrammed by an AI, and with which we accept major life changes which, while we sometimes chose them, often result in severe and unpredictable (as per the article) changes of your utility function, your terminal values and whatever else constitutes your identity.

The difference may lie partly in the scope of the transformation, but then again, think of the moron you (yes, you) probably consider your 10 years younger self. Would it be so strange to have reached your present self when hypothetically exchanging your past self with some friend/peer? That's how much/little is preserved. However, I'd expect most of the difference being due to an "agenty" process changing you invoking more self-defense reflexes than the supposedly more "random" process of just living your life.

EDIT: For a more entertaining if hyperbolic example, it's like saying "Never change a thing about my like for Beethoven, or for this particular brand of Irish Whiskey. These are irreducible, terminal values! Wait, there's a button which is gonna randomize me from head to toe, it says "marry, get children". Alright, here we gooooo!"

There is a curious disparity between the ardor with which we tackle the issue of defending against being reprogrammed by an AI, and with which we accept major life changes which, while we sometimes chose them, often result in severe and unpredictable (as per the article) changes of your utility function, your terminal values and whatever else constitutes your identity.

Is that just an LW-specific cultural attitude? Ben Goertzel doesn't seem to think that value drift from a non-CEV AI would be that terrible. It occurred to me that the path humanity has taken already through technological and cultural development is a very poor approximation of CEV, and yet we're likely happier today than we were in the ancestral environment.

and yet we're likely happier today than we were in the ancestral environment.

Well, if my goal were to be replaced by something different from me that is happier doing whatever it ends up doing than I am doing what I do, that's relatively simple. But it doesn't actually seem to be an adequate description of my goal.

Do you think a typical hunter-gatherer would be happy to be transported to the modern world?

Fair question. I'm not sure.

Immediately upon being transported, certainly not.

I suppose I'm weakly confident that they would experience more happiness over the course of their lives than they would have had they not been so transported, mostly by virtue of avoiding or deferring various happiness-reducing conditions (e.g. disease, death, pain, malnutrition, death-of-loved-ones, etc.).

This is largely an expression of my belief that there hasn't in fact been that much value drift between then and now, and my willingness to treat happiness as a rough measure of compliance-with-values (aka utility). If I believed there were a lot of value drift, my confidence would decrease.

If at time T there's a fully-compliant-with-my-values system controlling my environment, I similarly expect less utility at some later time if that system experiences value drift than if it doesn't.

Generally agree, but I don't think the situation is quite as bad as this, for two reasons. First, I agree that stated preferences can change drastically over time, but I suspect that actual preferences are more stable. Second, introspection is difficult and humans are not automatically strategic, so people are both unlikely to have a good grasp of their own preferences and unlikely to reliably take actions to satisfy even what they believe their preferences to be. Life changes that look like they're changing your preferences might just be life changes that help you get a better grasp of your existing preferences or get better ideas about how to satisfy them.

My guess is that the life changes that are most likely to change your actual preferences are those associated with biological mechanisms, e.g. puberty and the biological clock. The ones most likely to change your stated preferences might be those associated with substantial shifts in your peer group, e.g. going to college. Either way, these kinds of shifts both have the property that everyone else is going through them too, so at least they're not weird shifts.

Kawoomba, judging from my conversations with him, believes that stated preferences are all there is. When you convince someone they were wrong, their terminal values change. So naturally he views this prospect as rather more common, and undervalued.

Agree.

On the other hand, I don't think of my 10 years younger self as a moron, just naive. I don't think I've changed all that much, even, though sometimes I'd like to think I have. It's possible that part of the reason for the bias described in the study is that we overestimate the changes we've gone through in the last 10 years.

Would it be so strange to have reached your present self when hypothetically exchanging your past self with some friend/peer?

Well, yes, in that we'd have to explain how my present self ended up with memories of what are now my friend/peer's experiences, among other things. Any explanation of that is bound to be pretty damned strange.

That said, I do agree with the general principle that the differences between me at various different times are potentially radical enough that definitions of "my identity" based on similarities will pick out a different set of person-moments than those based on continuity. Personally, I'm content using a pretty broad similarity-based definition that includes lots of discontinuous person-moments, but others' mileage varies.

I don't think that your declarative/explicit memory is all that important to your identity, the influence those experiences had on your cognitive algorithms, certainly, but the explicit memories themselves? Of course any path that would take a 10-years-younger peer of yours to your current identity would be strange, even somewhat stranger than the semi-random walk you yourself took. But it is conceivable, i.e. your past and long gone personae were part of your path through time and space to your current self, but they aren't strictly necessary to get to where you are now. Mostly, they're just gone.

Of course any path that would take a 10-years-younger peer of yours to your current identity would be strange, even somewhat stranger than the semi-random walk you yourself took.

I'm no longer sure what you mean by "your current identity" in that sentence, so let me try to taboo it.

Consider person X, my friend of ten years ago. I distinctly remember that ten years ago, X called himself George and described himself as having been born in Atlanta, whereas I called myself Dave and described myself as having been born in New Jersey.

Right now, I call myself Dave and describe myself as having been born in New Jersey.

Any path that takes X from where he was ten years ago to exactly the state I'm in right now, which includes calling myself Dave and describing myself as having been born in New Jersey, is very very strange... far stranger than the path I myself took, and stranger than .999999999 of the paths that were available for me to take.

Any path that takes X from where he was ten years ago to some state that shares some elements with the state I'm in right now, but not others, may be less strange than that. It may even be less strange than the path I myself took. It depends on which shared elements we're talking about.

I agree that many elements of the state I'm in right now don't matter very much.

"What's in a name? That which we call a rose
By any other name would smell as sweet."

I agree that many elements of the state I'm in right now don't matter very much.

Yea, e.g. lots of variables share the name "x". It's just denoting that which you talk about, and while a name can influence your upbringing (say it's a foreign name), i.e. while it'll help take you to your current utility function, at least I would not consider it crucial for identity purposes having reached the present time (yet it is essential for daily life, of course). Hopefully that makes my example clearer, if not steelman it as you see fit :), I think even without it my point is comprehensible.

As I said, I wasn't sure what you meant by "current identity", which is why I provided two versions of what you might mean.

I was hoping you might endorse one or the other of them, but oh well.

Anyway, yes, if we generalize your point about my name to also include where I was born and what my native language was and what religion I was raised in and the million other demographic data that distinguish me from my ten-years-ago peer, then I agree with you.

Funny, the psychologist Robert Sapolsky has written about how people's ability to seek and appreciate novelty seems to fall into a developmental window which closes in our 30's, as we can see from older people's resistance to listening to new genres of music or developing tastes for new kinds of food. That would explain why Baby Boomers still listen to the music they grew up with in the 1960's and 1970's, but they resist eating sushi because that didn't become widely available in the U.S. until the 1980's, after their novelty-seeking phase ended.

I turned 53 back in November, however, and I seem to have less of a problem with that. I recognize the music I grew up with when I hear it on oldies stations or internet channels, but I don't seek it out. In the past 15 years or so I've started to listen to jazz and Celtic music, I eat sushi on occasion and I have even developed a fondness for cats, when previously I didn't care for them. (The Babelfish-like Toxoplasma gondii parasite has probably taken over my brain and turned me into a cat-adoring zombie.)

This phenomenon has some bearing on my current frustrations with the direction of the cryonics movement, because to me many older cryonicists look like they haven't evolved mentally from the time they read certain influential books early in their lives. I don't claim exemption from that tendency, of course, but I chuckled recently when I read a post on New Cryonet by someone who claimed that he learned everything he needed to know about economics from Ludwig von Mises's Human Action. Suppose we could bring back to life an educated, English-speaking individual from the 18th Century who resisted the effort to update his thinking for the 21st Century because he thought he learned everything he needed to know from the books he read 250 years ago? "I mastered everything I need to know about political economy from the pamphlets of the French Physiocrats, thank you, sir."

I've also noticed this tendency in Alcor's CEO, who still refers to Julian L. Simon's famous wager with Paul Ehrlich as an alleged vindication of Simon's cornucopianism over Ehrlich's Malthusianism, even though Peter Thiel has pointed out recently that trends in commodities prices have supported Ehrlich's side of the wager since the 1990's.

And, of course, I have a huge problem now with basing cryonics' propaganda & apologetics on Eric Drexler's fantasies from the 1980's about capital-N Nanotechnology, when that looks increasingly unarrivable. How many more decades have to pass before cryonicists give up on this mirage and look for real technological paths to revival? And why do I have the cognitive plasticity to see this, but apparently no other cryonicist has reached a similar conclusion?

Reference:

Is there some way us young people can precommit now to taking the outside view and being heavily influenced by the young people of tomorrow when we're old?

If any young person of the future is having an disagreement with me and happens across this decades-old comment, feel free to use it as an argument for your side.

Is there some way us young people can precommit now to taking the outside view and being heavily influenced by the young people of tomorrow when we're old?

"To stay young requires unceasing cultivation of the ability to unlearn old falsehoods."

Yeah, that's the obvious first step. I'm just looking for ways to add redundancy.

people of any age X predicted less difference with their X+10 selves than people of age X+10 recollected of themselves at age X.

I didn't read the article, or the study, but I'm curious why they conclude "we predict less change than we will actually experience" from this rather than "we recollect more change than we actually experienced."

Regardless, I agree with the conclusion about taking the Outside View.

I'm curious why they conclude "we predict less change than we will actually experience" from this rather than "we recollect more change than we actually experienced."

The authors were aware of this issue and they addressed it twice in the paper. First, for study 1 (p. 96, column 3):

we compared the magnitudes of the predicted and reported personality changes in our sample to the magnitude of actual personality change observed in an independent sample of 3808 adults,

and found that the intraclass correlation of the reported personality changes in their sample matches the intraclass correlation of the actual personality changes in the independent sample. (This is consistent with memory being reliable, but it is not conclusive evidence.)

Second, (p. 98, column 1):

in study 3 we examined the end of history illusion in a domain in which memory was likely to be highly reliable. Rather than asking reporters to remember how extraverted they had been or how much they had once valued honesty, we asked them to remember simple facts about their strongest preferences, such as the name of their favorite musical band or the name of their best friend.

They found the same effect in study 3 as the one that they found in study 1 (suggesting that faulty memory is not the sole cause of the effect), but Ellenberg (which Qiaochu_Yuan linked to) has a critique of study 3 (as well as other parts of the paper).

Cool. Thanks for the summary!

I think this is a really good question. I might suppose that people intuitively trust memory more than prediction and so when they see the two don't match they assume its the prediction that's wrong.

That said, one thing we know from research is that memory is really unreliable. It removes things , adds details, changes when you tell or hear stories, shifts to fit narratives, etc. I wonder if our instinct here ought to be that if memory and prediction don't match it's because the memory changed and not that the prediction was wrong.

I don't think I've changed that much over the past ten years.

I've gone from believing pretty firmly I was asexual to happily embracing bisexuality. I've picked up smoking and drinking, habits I never would have considered then. I've stopped putting 100% into my work (as a result of my bosses complaining about my productivity, actually - being able to fit forty hours of work for a relatively bright person into two hours is detrimental when you're doing paid-by-the-hour consulting for clients; it's impossible to keep enough work queued up to remain profitable). I've tried recreational drugs, another thing I would never have considered then.

But oddly enough, I don't think my outlooks have changed all that much at all; it's almost all been knowledge. The most sizable change to my outlook has been coming to terms with my own mortality.

answering about the present, about themselves 10 years earlier, and about what they expected 10 years hence. They generally reported greater differences between their earlier selves and their present than between their present and future selves.

Nitpick: The comparison was done between predictors and reporters across the same range in age:

Participants were randomly assigned either to the reporter condition (and were asked to complete the measure as they would have completed it 10 years earlier) or the predictor condition (and were asked to complete the measure as they thought they would complete it 10 years hence).

In other words, they compared the 10-year predictions of 18-year-olds to the 10-year reports of 28-year-olds. This is different from (and better than) comparing the 10-year reports and predictions of the same age group.

Agreed.

Ah, I misinterpreted what you wrote in the OP. I suggest replacing this sentence in the OP

They generally reported greater differences between their earlier selves and their present than between their present and future selves.

with something like what you wrote in reply to nyan_sandwich (which I found much clearer):

Age X predicts less difference in the next 10 years than age X+10 recollects in the last 10 years.

"The single best way to make predictions about what you're going to want in the future isn't to imagine yourself in the future, … it's to look at other people who are in the very future you're imagining,"

I was aiming for something like this sort of information with Seeking book about baseline life planning and expectations. That turned up numerous suggestions for tangentially related content that I could try to collate for myself, but nothing that addresses the desire squarely. If anyone knows of something in this vein, I'd still appreciate a pointer to solid content on the subject :-)

I wonder how this bias manifests in us lesswrongians. How has your rationality changed over the last 5 years? How do you expect it to change in the coming 5?

For that matter, how do we apply the "Outside View" advice? Based on the LessWrong survey results, "look at the general population of age X" is a lousy way to predict an average lesswrongian's personality at age X; presumably that's true for age X+10 too. "If you match the average of lesswrongians at age X, look for their average at age X+10" might be decent advice under the cynical view that "having had 10 extra years to read LessWrong won't lead to significant personality changes", if the data wasn't too sparse.

[-][anonymous]9y 0

The quotations and summary imply they went directly to "therefor people are bad predictors" without passing through "they made bad predictions"

For example, it's not impossible for the past to always be more different from the present than the future is; they could be exponentially approaching a stable self. This is in fact the impression I've gotten from all the talk of old people not changing their minds, people implementing simulated annealing, young people being radical and fickle, etc.

I think the conclusion is probably correct and interesting, but the evidence as quoted only weakly supports it.

For example, it's not impossible for the past to always be more different from the present than the future is; they could be exponentially approaching a stable self.

Yes, they report a decline in change with age [1], but even allowing for that, they find that people underpredict how different they will be. Age X predicts less difference in the next 10 years than age X+10 recollects in the last 10 years.

[1] It should be noted that these studies were not longitudinal, which introduces another class of possible error. They never compared any individual's actual traits at different ages, only different individuals of different ages at the time of the tests.

[-][anonymous]9y 2

Ok, thanks for clearing that up.