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The Philippines said Wednesday it is banning the use of heavy-weighted fishing nets that drag along the ocean floor inflicting damage to seabed communities and coral reefs.
The Philippines said Wednesday it is banning the use of heavy-weighted fishing nets that drag along the ocean floor inflicting damage to seabed communities and coral reefs.
18 minutes ago
Newcomb’s paradox is the name usually given to the following problem. You are playing a game against another player, often called Omega, who claims to be omniscient; in particular, Omega claims to be able to predict how you will pl...
Newcomb’s paradox is the name usually given to the following problem. You are playing a game against another player, often called Omega, who claims to be omniscient; in particular, Omega claims to be able to predict how you will play in the game. Assume that Omega has convinced you in some way that it is, if not omniscient, at least remarkably accurate: for example, perhaps it has accurately predicted your behavior many times in the past. Omega places before you two opaque boxes. Box A, it informs you, contains $1,000. Box B, it informs you, contains either $1,000,000 or nothing. You must decide whether to take only Box B or to take both Box A and Box B, with the following caveat: Omega filled Box B with $1,000,000 if and only if it predicted that you would take only Box B. What do you do? (If you haven’t heard this problem before, please take a minute to decide on an option before continuing.) The paradox The paradox is that there appear to be two reasonable arguments about which option to take, but unfortunately the two arguments support opposite conclusions. The two-box argument is that you should clearly take both boxes. You take Box B either way, so the only decision you’re making is whether to also take Box A. No matter what Omega did before offering the boxes to you, Box A is guaranteed to contain $1,000, so taking it is guaranteed to make you $1,000 richer. The one-box argument is that you should clearly take only Box B. By hypothesis, if you take only Box B, Omega will predict that and will fill Box B, so you get $1,000,000; if you take both boxes, Omega will predict that and won’t fill Box B, so you only get $1,000. The two-boxer might respond to the one-boxer as follows: “it sounds like you think a decision you make in the present, at the moment Omega offers you the boxes, will affect what Omega did in the past, at the moment Omega filled the boxes. That’s absurd.” The one-boxer might respond to the two-boxer as follows: “it sounds like you think you can just make decisions without Omega predicting them. But by hypothesis he can predict them. That’s absurd.” Now what do you do? (Again, please take a minute to reassess your original choice before continuing.) The von Neumann-Morgenstern theorem Let’s avoid the above question entirely by asking some other questions instead. For example, a question one might want to ask after having thought about Newcomb’s paradox for a bit is “in general, how should I think about the process of making decisions?” This is the subject of decision theory, which is roughly about decisions in the same sense that game theory is about games. The things that make decisions in decision theory are abstractions that we will refer to as agents. Agents have some preferences about the world and are making decisions in an attempt to satisfy their preferences. One model of preferences is as follows: there is a set of (mutually exclusive) outcomes, and we will model preferences by a binary relation on outcomes describing pairs of outcomes such that the agent weakly prefers to . This means either that in a decision between the two the agent would pick over (the agent strictly prefers to ; we write this as ) or that the agent is indifferent between them. The weak preference relation should be a total preorder; that is, it should satisfy the following axioms: Reflexivity: . (The agent is indifferent between an outcome and itself.) Transitivity: If and , then . (The agent’s preferences are transitive.) Totality: Either or . (The agent has a preference about every pair of outcomes.) If and then this means that the agent is indifferent between the two outcomes; we write this as . The axioms above imply that indifference is an equivalence relation. The strong assumptions here are transitivity and totality. One reason to
21 minutes ago
An international team of astronomers has discovered an exotic young planet that is not orbiting a star. This free-floating planet, dubbed PSO J318.5-22, is just 80 light-years away from Earth and has a mass only six times that of Jupiter...
An international team of astronomers has discovered an exotic young planet that is not orbiting a star. This free-floating planet, dubbed PSO J318.5-22, is just 80 light-years away from Earth and has a mass only six times that of Jupiter. The planet formed a mere 12 million years ago -- a newborn in planet lifetimes.
27 minutes ago
A judge on Wednesday ordered the accused mastermind of nefarious online bazaar Silk Road shipped to New York to stand trial.
A judge on Wednesday ordered the accused mastermind of nefarious online bazaar Silk Road shipped to New York to stand trial.
32 minutes ago
Astronomers have captured an image of an unusual free-floating planet. As the object has no host star, it can be observed and examined much easier than planets orbiting stars, promising insight into the details of planetary atmospheres.
Astronomers have captured an image of an unusual free-floating planet. As the object has no host star, it can be observed and examined much easier than planets orbiting stars, promising insight into the details of planetary atmospheres.
32 minutes ago
Though summer has come to an end – at least in the Northern Hemisphere – your feedback on the new Google Maps preview these past three months has been a great help in our continuing quest to build a better map, more tailored to you. Base...
Though summer has come to an end – at least in the Northern Hemisphere – your feedback on the new Google Maps preview these past three months has been a great help in our continuing quest to build a better map, more tailored to you. Based on your input, we’re pleased to announce one of your most requested features – directions for multiple destinations – will begin rolling out today. And with two new tools to help manage your reservations and discover upcoming events, it's never too early to plan your next road trip or adventure. Directions for multiple destinations Whether you’re running weekend errands or planning a cross-country tour, you can plot multiple destinations for your trip with ease – now available for driving, walking and biking directions. Once you’ve chosen a starting point, click '+' and add stops to your route by typing in the search box or clicking on the map. Plan your next road trip with directions for multiple destinations When you’re exploring a new city, find the best way to museums, historic squares, and other attractions by dragging and dropping your destinations in the order that works for you. And if you’re curious before you go, the Views carousel, located in the bottom right corner, is a great way to preview Street View, Photo Tours, and other imagery. Re-order your route by dragging and dropping one destination above or below another See your flight, hotel, and restaurant reservations Similar to Google Search, find your flight, hotel, and restaurant reservations faster right in Maps. Just search for your departing airport or dining destination, and we’ll instantly show your upcoming plans. Having all your stuff in one place makes it easier to manage your appointment details and plan your commute. This info is available when you're signed into Google, and only you can see it. Then, when you're ready to go, you can quickly access your recent search history on the Google Maps app for your iPhone or Android device and hit the road This feature is currently rolling out to Maps users in the U.S. and is available in English only. When signed into Google, locate your destination on desktop and access search history on mobile to quickly navigate there Upcoming Events Search for Radio City Music Hall, the O2 Arena, or your favorite local performance venues, and click on the Upcoming Events card to see a schedule of concerts, sports matches, and other events happening near you. Or if you’re new to an area, start with "music venues." See a schedule of performances and sports matches with the Upcoming Events card It's been a busy summer for the Maps team, and we wanted to share a few things we've been working on, but there's a lot more coming soon. Keep sending us your feedback using the "Help & Feedback" menu in the upper right corner of the screen. Posted by Florian Goerisch, Product Manager, Google Maps
32 minutes ago
The Wait But Why blog has an amusing post on why Generation Y yuppies (GYPSYS) are unhappy, which I found through the blog of Michigan economist  Miles Kimball. In short, it is because their expectations exceed reality and they are entit...
The Wait But Why blog has an amusing post on why Generation Y yuppies (GYPSYS) are unhappy, which I found through the blog of Michigan economist  Miles Kimball. In short, it is because their expectations exceed reality and they are entitled. What caught my eye was that they defined happiness as “Reality-Expectations”. The key point being that this is a subtractive expression. My college friend Peter Lee, now Professor and Director of the University Manchester X-Ray imaging facility, used to define happiness as “desires fulfilled beyond expectations”. I always interpreted this as a divisive quantity, meaning “Reality/Expectations”. Now, the definition does have implications if we actually try to use it as a model for how happiness would change with some quantity like money. For example, consider the model where reality and expectations are both proportional to money. Then happiness = a*money – b*money. As long as b is less than a, then money always buys happiness, but if a is less than b then more money brings more unhappiness. However, if we consider the divisive model of happiness then happiness = a*money/ b*money = a/b and happiness doesn’t depend on money at all. However, the main reason I bring this up is because it is analogous to the two possible ways to model inhibition (or adaptation) in neuroscience. The neurons in the brain generally interact with each other through two types of synapses – excitatory and inhibitory. Excitatory synapses generally depolarize a neuron and make its potential get closer to threshold whereas inhibitory neurons hyperpolarize the neuron and make it farther from threshold (although there are ways this can be violated). For neurons receiving stationary asynchronous inputs, we can consider the firing rate to be some function of the excitatory E and inhibitory I inputs. In subtractive inhibition, the firing rate would have the abstract form f(E-I) whereas for divisive inhibition it would have the form f(E)/(I+C), where f is some thresholded gain function (i.e. zero below threshold, positive above threshold) and C is a constant to prevent the firing rate from reaching infinity. There are some critical differences between subtractive and divisive inhibition. Divisive inhibition works by reducing the gain of the neuron, i.e. it makes the slope of the gain function shallower while subtractive inhibition makes the threshold effectively higher. These properties have great computational significance, which I will get into in a future post.
39 minutes ago
Remember when people used personal computers—desktops and laptops—to check email, view video and keep tabs on Facebook? Back in that far-away era, I'd have several windows open for Web browsers, a word processor, a photo editor and somet...
Remember when people used personal computers—desktops and laptops—to check email, view video and keep tabs on Facebook? Back in that far-away era, I'd have several windows open for Web browsers, a word processor, a photo editor and sometimes a reader for PDF documents.
42 minutes ago
Ahmir Thompson, aka ?uestlove from The Roots, and their producer, Steven Mandel, are secret "Elvis freaks." One of their early discussions about agreeing to their gig on Late Night With Jimmy Fallon was the possibility about playing with...
Ahmir Thompson, aka ?uestlove from The Roots, and their producer, Steven Mandel, are secret "Elvis freaks." One of their early discussions about agreeing to their gig on Late Night With Jimmy Fallon was the possibility about playing with Elvis. The Roots took the job, and Elvis has now played on the show five times. From these collaborations, the seeds of something bigger grew, and that came to a very funky (and political) fruition with Wise Up Ghost, embedded as streaming tracks in this Guardian review, and available in a single stream from a fan on YouTube. If you'd like to hear more about how the "remixing" of some prior Costello pieces (Pills and Soap, National Ramson, and Hurry Down Doomsday, to name a few songs), Costello and Thompson spent about 40 minutes with NPR's World Cafe, or you can read their interview with the Guardian.
about 1 hour ago
Habitually verbose pontificator Will Self reviews the latest tome from Mark Kermode - Britain's Rockabilly Ebert - and in doing so, reviews the changing nature of criticism.
Habitually verbose pontificator Will Self reviews the latest tome from Mark Kermode - Britain's Rockabilly Ebert - and in doing so, reviews the changing nature of criticism.
about 1 hour ago