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Our Brain Uses Statistics to Calculate Confidence, Make Decisions

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Re: Our Brain Uses Statistics to Calculate Confidence, Make Decisions

#21

Post by Bartweiss »

haberman wrote: post #12

> It is Kepecs' thesis that statistics - generated by the objective processing of sensory and other data - is the ultimate language of the brain. Every time I read stuff like this, I lose more confidence that the scientific method as currently applied, funded, and published is capable of truly conquering complex systems like the brain or nutrition. I read article after article like this one, where a prominent researc…

While I agree that this seems like "scientist has pet theory, does study to prove it", I don't think the bias/irrationality claims disprove much.

The way to reconcile those claims is to say that many of our statistical/estimation patterns are very bad. Mostly, they were good once, but are completely unequipped to deal with the modern world. I know "we're optimized for the savannah" is a laugh-line at this point, but it doesn't seem absurd to claim that we're using statistical techniques that are easy but inflexible. Flawless Bayesian updating is basically unachievable, and a lot of our biases seem like once-useful heuristics that screw us a lot in the modern world.

Tetlock's Superforcasting seems like a good reference here: it's a study of people who are uncommonly good at estimating future probabilities. These are people who estimate near-future events to better than half a percent (as in, rounding from .1% to .5% reliably lowers their accuracy). Most of them claim to use a lot of numerical probability estimates, which suggests that they might be employing an existing system consciously to get the bugs out.

None of this means I buy the study, but I'm not willing to reject the hypothesis, either. Given that we're running on neural nets, I wouldn't be surprised if we deal in actually probabilities and are just exceedingly bad at it.

Re: Our Brain Uses Statistics to Calculate Confidence, Make Decisions

#22

Post by IanCal »

stormbrew wrote: post #9
danharaj wrote: post #5

It's interesting how the reification of statistical reasoning, that is, understanding statistics symbolically and applying it to abstract symbols is far more fraught than the implicit statistical reasoning that this article describes.

Your brain is also able to calculate the parabolic arc of a baseball someone threw to you whether or not you could ever do it on paper.

That's not quite true. When catching a ball we constantly adjust as we go so we're not perfectly calculating where it will land. We can train humans to roughly approximate where a ball will land, that's about it.

Re: Our Brain Uses Statistics to Calculate Confidence, Make Decisions

#23

Post by CyberDildonics »

rudolf0 wrote: post #3
kensai wrote: post #2

"The work may also have wider implications. The fields of statistics and, in particular, machine learning, may have something to learn from this inner statistician. "Humans are still better than computers at solving really difficult problems," says Kepecs." Intuitive as Statistics is simply one of the many tools we humans use to tackle difficult problems, but definitely not the only one.

But it is a little disheartening (yet also exciting) to think that when an AI is eventually developed with a human's intuition, creativity, and learning ability, we'll essentially have no advantages over them.

If we could make a machine better than us in every way, why couldn't that machine make us better in every way?

Re: Our Brain Uses Statistics to Calculate Confidence, Make Decisions

#25

Post by haberman »

Bartweiss wrote: post #21
haberman wrote: post #12

> It is Kepecs' thesis that statistics - generated by the objective processing of sensory and other data - is the ultimate language of the brain. Every time I read stuff like this, I lose more confidence that the scientific method as currently applied, funded, and published is capable of truly conquering complex systems like the brain or nutrition. I read article after article like this one, where a prominent researc…

While I agree that this seems like "scientist has pet theory, does study to prove it", I don't think the bias/irrationality claims disprove much. The way to reconcile those claims is to say that many of our statistical/estimation patterns are very bad . Mostly, they were good once, but are completely unequipped to deal with the modern world. I know "we're optimized for the savannah" is a laugh-line at this point, but…

> The way to reconcile those claims is to say that many of our statistical/estimation patterns are very bad.

If studies like this one are taken as evidence of a statistical mind, then non-statistical behavior has to be taken as evidence of a non-statistical mind. Otherwise we have a non-falsifiable theory.

Experiment shows mind behaving statistically: "mind is statistical."

Experiment shows mind behaving non-statistically: "mind is statistical, but this scenario exceeds its capabilities."

> which suggests that they might be employing an existing system consciously to get the bugs out.

I should clarify -- I have nothing against the idea that our minds employ statistical methods. In fact I'm sure they must.

I'm opposed to taking that kernel of truth and pushing a reductionist understanding of something extremely complex (the brain).

Re: Our Brain Uses Statistics to Calculate Confidence, Make Decisions

#26

Post by gph »

haberman wrote: post #18
Lxr wrote: post #16

Earlier quoted context omitted.

> How does a brain built on statistics decide that this is the most rational course of action? The article suggests that humans have an innate means of determining confidence in a particular hypothesis based on evidence. Why does this imply they act rationally?

> The article suggests that humans have an innate means of determining confidence in a particular hypothesis based on evidence. Yes. In my example, the hypothesis is "killing all of our cattle will make the spirits of our ancestors come to our aid." The evidence supporting this hypothesis was nonexistent. And yet the people expressed extreme confidence in this hypothesis by killing all of their cattle.

>The evidence supporting this hypothesis was nonexistent

The rational evidence was nonexistent. I don't think this theory is necessarily built on the idea that humans evaluate evidence rationally.

Re: Our Brain Uses Statistics to Calculate Confidence, Make Decisions

#27

Post by everly »

haberman wrote: post #18
Lxr wrote: post #16

Earlier quoted context omitted.

> How does a brain built on statistics decide that this is the most rational course of action? The article suggests that humans have an innate means of determining confidence in a particular hypothesis based on evidence. Why does this imply they act rationally?

> The article suggests that humans have an innate means of determining confidence in a particular hypothesis based on evidence. Yes. In my example, the hypothesis is "killing all of our cattle will make the spirits of our ancestors come to our aid." The evidence supporting this hypothesis was nonexistent. And yet the people expressed extreme confidence in this hypothesis by killing all of their cattle.

I think you're using a definition of 'evidence' that is too narrow or perhaps too logical, although I agree with pretty much everything you're saying.

I think that the statistical theory is possible but certainly couldn't be objective (one big reason being the cognitive biases you mentioned). Meaning a person will do the necessary mental gymnastics to assign the necessary value to the variable 'evidence' that their brain uses.

In your example, I think some combination of religious belief, regret avoidance, and herd thinking all added up to equal the requisite 'evidence' needed to express confidence in the cattle killing hypothesis.

Re: Our Brain Uses Statistics to Calculate Confidence, Make Decisions

#28

Post by steego »

haberman wrote: post #12

> It is Kepecs' thesis that statistics - generated by the objective processing of sensory and other data - is the ultimate language of the brain. Every time I read stuff like this, I lose more confidence that the scientific method as currently applied, funded, and published is capable of truly conquering complex systems like the brain or nutrition. I read article after article like this one, where a prominent researc…

> For example, the time that the prophecy of a teenage girl convinced a tribe of people in present-day South Africa to kill 300,000 - 400,000 of their own cattle, leading to the starvation and death of 20,000 - 40,000 people. How does a brain built on statistics decide that this is the most rational course of action?

That's actually a really good example of statistics deciding a course of action.

Ask yourself this? Why did they believe it? It's most likely that group of people were repeatedly told stories that belongs to a larger framework of belief. What you might not understand is good literature has a tendency to fire parts of the brain related to sight, sound and touch in an fMRI. For so many people, a good story creates a parallel quasi-reality, and I wouldn't be surprised their brain is basically chalking up those stories as real experiences.

I was just listening to a story on This American Life about some kids whose prom was interrupted by a tornado. What shocked me was how many of these kids created internal narratives that they somehow caused the storm, or the storm was manifested as a personal lesson for them. If you think about the garbage plot lines and religious upbringing people absorb, this sort of narcissistic outlook makes a tremendous amount of sense.

I'll add this one point. Modern public relations and politics feeds on the principle that you can manufacture reality by constantly bombarding people with the same shallow message. It doesn't matter what you say as much as how loud and frequent you're saying it.

Re: Our Brain Uses Statistics to Calculate Confidence, Make Decisions

#29

Post by dperfect »

haberman wrote: post #18
Lxr wrote: post #16

Earlier quoted context omitted.

> How does a brain built on statistics decide that this is the most rational course of action? The article suggests that humans have an innate means of determining confidence in a particular hypothesis based on evidence. Why does this imply they act rationally?

> The article suggests that humans have an innate means of determining confidence in a particular hypothesis based on evidence. Yes. In my example, the hypothesis is "killing all of our cattle will make the spirits of our ancestors come to our aid." The evidence supporting this hypothesis was nonexistent. And yet the people expressed extreme confidence in this hypothesis by killing all of their cattle.

Perhaps it would be more accurate to say "humans have an innate means of determining confidence in a particular hypothesis based on perceived evidence".

From an objective standpoint, evidence is either black or white. But for our brains, beliefs and biases may be given equal weight with objective truth. Whether or not those beliefs are rooted in truth is a question ultimately controlled by each person's worldview and their understanding of scientific reasoning. The underlying algorithms may still be based on statistics, albeit statistics with unreliable data.

Or, in the example provided, perhaps the tribe's statistical models were warped enough by cultural/religious/conventional wisdom (unreliable data) that they really did express a high level of confidence in an otherwise outlandish idea - a confidence based on statistically sound evaluation, only fed with bad data.

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