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Link: The Economist on Paperclip Maximizers
I certainly was not expecting the Economist to publish a special report on paperclip maximizers (!).
As the title suggests, they are downplaying the risks of unfriendly AI, but just the fact that the Economist published this is significant
Link: Evidence-Based Medicine Has Been Hijacked
John Ioannidis has written a very insightful and entertaining article about the current state of the movement which calls itself "Evidence-Based Medicine". The paper is available ahead of print at http://www.jclinepi.com/article/S0895-4356(16)00147-5/pdf.
As far as I can tell there is currently no paywall, that may change later, send me an e-mail if you are unable to access it.
Retractionwatch interviews John about the paper here: http://retractionwatch.com/2016/03/16/evidence-based-medicine-has-been-hijacked-a-confession-from-john-ioannidis/
(Full disclosure: John Ioannidis is a co-director of the Meta-Research Innovation Center at Stanford (METRICS), where I am an employee. I am posting this not in an effort to promote METRICS, but because I believe the links will be of interest to the community)
Clearing An Overgrown Garden
(tl;dr: In this post, I make some concrete suggestions for LessWrong 2.0.)
Less Wrong 2.0
A few months ago, Vaniver posted some ideas about how to reinvigorate Less Wrong. Based on comments in that thread and based on personal discussions I have had with other members of the community, I believe there are several different views on why Less Wrong is dying. The following are among the most popular hypotheses:
(1) Pacifism has caused our previously well-kept garden to become overgrown
(2) The aversion to politics has caused a lot of interesting political discussions to move away from the website
(3) People prefer posting to their personal blogs.
With this background, I suggest the following policies for Less Wrong 2.0. This should be seen only as a starting point for discussion about the ideal way to implement a rationality forum. Most likely, some of my ideas are counterproductive. If anyone has better suggestions, please post them to the comments.
Moderation Policy:
There are four levels of users:
- Users
- Trusted Users
- Moderators
- Administrator
Personal Blogs:
Other Ideas:
Meetup : Palo Alto Meetup: Lightning Talks
Discussion article for the meetup : Palo Alto Meetup: Lightning Talks
Be prepared to talk for 5 minutes about any subject!
Discussion article for the meetup : Palo Alto Meetup: Lightning Talks
Meetup : Palo Alto Meetup: Introduction to Causal Inference
Discussion article for the meetup : Palo Alto Meetup: Introduction to Causal Inference
Anders Huitfeldt will give an introductory talk about causal reasoning and the distinction between causal inference and statistical inference
The meetup is at 6:30pm on Tuesday Jan 19th at the group house Tesseract in Palo Alto. Allergen notes: Cats and Dogs
Discussion article for the meetup : Palo Alto Meetup: Introduction to Causal Inference
Meetup : Palo Alto Meetup: The Economics of AI
Discussion article for the meetup : Palo Alto Meetup: The Economics of AI
Edward will give a talk about the Economics of AI and its implications for the Singularity Hypothesis
The meetup is at 6:30pm on Tuesday Jan 5th at the group house Tesseract in Palo Alto. Allergen notes: Cats and Dogs
Discussion article for the meetup : Palo Alto Meetup: The Economics of AI
Post-doctoral Fellowships at METRICS
On stopping rules
(tl;dr: In this post I try to explain why I think the stopping rule of an experiment matters. It is likely that someone will find a flaw in my reasoning. That would be a great outcome as it would help me change my mind. Heads up: If you read this looking for new insight you may be disappointed to only find my confusion)
(Edited to add: Comments by Manfred and Ike seem to point correctly to the critical flaws in my reasoning. I will try to update my intuition over the next few days)
In the post "Don't You Care If It Works Part 1" on the Main section of this website, Jacobian writes:
A few weeks ago I started reading beautiful probability and immediately thought that Eliezer is wrong about the stopping rule mattering to inference. I dropped everything and spent the next three hours convincing myself that the stopping rule doesn't matter and I agree with Jaynes and Eliezer. As luck would have it, soon after that the stopping rule question was the topic of discussion at our local LW meetup. A couple people agreed with me and a couple didn't and tried to prove it with math, but most of the room seemed to hold a third opinion: they disagreed but didn't care to find out. I found that position quite mind-boggling. Ostensibly, most people are in that room because we read the sequences and thought that this EWOR (Eliezer's Way Of Rationality) thing is pretty cool. EWOR is an epistemology based on the mathematical rules of probability, and the dude who came up with it apparently does mathematics for a living trying to save the world. It doesn't seem like a stretch to think that if you disagree with Eliezer on a question of probability math, a question that he considers so obvious it requires no explanation, that's a big frickin' deal!
First, I'd like to point out that the mainstream academic term for Eliezer's claim is The Strong Likelihood Principle. In the comments section, a vigorous discussion of stopping rules ensued.
My own intuition is that the strong likelihood principle is wrong. Moreover, there exist a small number of people whose opinion I give higher level of credence than Eliezer's, and some of those people also disagree with him. For instance, I've been present in the room when a distinguished Professor of Biostatistics at Harvard stated matter-of-factly that the principle is trivially wrong. I also observed that he was not challenged on this by another full Professor of Biostatistics who is considered an expert on Bayesian inference.
So at best, the fact that Eliezer supports the strong likelihood principle is a single data point, ie pretty weak Bayesian evidence. I do however value Eliezer's opinion, and in this case I recognize that I am confused. Being a good rationalist, I'm going to take that as an indication that it is time for The Ritual. Writing this post is part of my "ritual": It is an attempt to clarify exactly why I think the stopping condition matters, and determine whether those reasons are valid. I expect a likely outcome is that someone will identify a flaw in my reasoning. This will be very useful and help improve my map-territory correspondence.
--
Suppose there are two coins in existence, both of which are biased: Coin A comes up heads with probability 2/3 and tails with probability 1/3, whereas Coin B comes up heads with probability 1/3. Someone gives me a coin without telling me which one, my goal is to figure out if it is Coin A or Coin B. My prior is that they are equally likely.
There are two statisticians who both offer to do an experiment: Statistician 1 says that he will flip the coin 20 times and report the number of heads. Statistician 2 would really like me to believe that it is Coin B, and says he will terminate the experiment whenever there are more tails than heads. However, since Statistician 2 is kind of lazy and doesn't have infinite time, he also says that if he reaches 20 flips he is going to call it quits and give up.
Both statisticians do the experiment, and both experiments end up with 12 heads and 8 tails. I trust both Statisticians to be honest about the experimental design and the stopping rules.
In the experiment of Statistician 1, the probability of getting this outcome if you have Coin A was 0.1486, whereas the probability of getting this outcome if it was Coin B was 0.0092. The likelihood ratio is therefore 16.1521 and the posterior probability of Coin A (after converting the prior to odds, applying the likelihood ratio and converting back to probability) is 0.94.
In the experiment of Statistician 2, however, I can't just use the binomial distribution because there is an additional data point which is not Bernoulli, namely the number of coin flips. I therefore have to calculate, for both Coin A and Coin B, the probability that he would not terminate the experiment prior to the 20th flip, and that at that stage he would have 12 heads and 8 coins. Since the probability reaching 20 flips is much higher for Coin A than for Coin B, the likelihood ratio would be much higher than in the experiment of Statistician 1.
This should not be unexpected: If Statistician B gives me data that supports the hypothesis which his stopping rule was designed to discredit, then that data is stronger evidence than similar data coming from the neutral Statistician A.
In other words, the stopping rule matters. Yes, all the evidence in the trial is still in the likelihood ratio, but the likelihood ratio is different because there is an additional data point. Not considering this additional data point is statistical malpractice.
Meetup : Boston: Trigger action planning
Discussion article for the meetup : Boston: Trigger action planning
Mick Porter will be presenting on trigger action planning, which is a strategy taught by CFAR to systematize solutions to everyday problems.
Cambridge/Boston-area Less Wrong meetups start at 3:30pm on the first and third Sunday of every month.
The default location is at the Citadel Rationalist House in Porter Sq, at 98 Elm St, apt 1, Somerville (Occasionally, meetups take place at other locations, such as MIT or Harvard. This will be specified as needed)
Our default schedule is as follows:
—Phase 1: Arrival, greetings, unstructured conversation.
—Phase 2: The headline event. This starts promptly at 4pm, and lasts 30-60 minutes.
—Phase 3: Further discussion. We'll explore the ideas raised in phase 2, often in smaller groups.
—Phase 4: Dinner.
Discussion article for the meetup : Boston: Trigger action planning
Meetup : Boston: Making space in Interpersonal Interactions
Discussion article for the meetup : Boston: Making space in Interpersonal Interactions
Kate (from the blog Gruntled and Hinged) is going to be talking about a concept called holding space. Specifically she's going to focus on talking with people who are having emotions when you disagree with their reasoning for having those emotions.
Here's a cool intro: http://heatherplett.com/2015/03/hold-space/
As always, the talk will be followed by discussion, both about the feature presentation and general
Cambridge/Boston-area Less Wrong meetups start at 3:30pm on the first and third Sunday of every month.
The default location is at the Citadel Rationalist House in Porter Sq, at 98 Elm St, apt 1, Somerville (Occasionally, meetups take place at other locations, such as MIT or Harvard. This will be specified as needed)
Our default schedule is as follows:
—Phase 1: Arrival, greetings, unstructured conversation.
—Phase 2: The headline event. This starts promptly at 4pm, and lasts 30-60 minutes.
—Phase 3: Further discussion. We'll explore the ideas raised in phase 2, often in smaller groups.
—Phase 4: Dinner.
Discussion article for the meetup : Boston: Making space in Interpersonal Interactions
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