Shepard's universal law of generalization is a remarkable hypothesis about how intelligent organisms should perceive similarity. In its broadest form, the universal law states that the level of perceived similarity between a pair of stimuli should decay as a concave function of their distance when embedded in an appropriate psychological space. While extensively studied, evidence in support of the universal law has relied on low-dimensional stimuli and small stimulus sets that are very different from their real-world counterparts. This is largely because pairwise comparisons - as required for similarity judgments - scale quadratically in the number of stimuli. We provide direct evidence for the universal law in a naturalistic high-dimensional regime by analyzing an existing dataset of 214, 200 human similarity judgments and a newly collected dataset of 390, 819 human generalization judgments (N = 2406 US participants) across three sets of natural images. The Universal Law of Generalization Holds for Naturalistic Stimuli Statement of Relevance Humans constantly form generalizations, whether when trying to identify the color of an object or reasoning about which action to take based on past experiences.

Empirically, generalization between a training and a test stimulus falls off in close approximation to an exponential decay function of distance between the two stimuli in the "stimulus space" obtained by multidimensional scaling. Math(cid:173) ematically, this result is derivable from the assumption that an individual takes the training stimulus to belong to a "consequential" region that includes that stimulus but is otherwise of unknown location, size, and shape in the stimulus space (Shepard, 1987). As the individual gains additional information about the consequential region-by finding other stimuli to be consequential or nOl-the theory predicts the shape of the generalization function to change toward the function relating actual probability of the consequence to location in the stimulus space. This paper describes a natural connectionist implementation of the theory, and illustrates how implications of the theory for generalization, discrimination, and classification learning can be explored by connectionist simulation. Because we never confront exactly the same situation twice, anything we have learned in any previous situation can guide us in deciding which action to take in the present situation only to the extent that the similarity between the two situations is sufficient to justify generalization of our previous learning to the present situation.

Spherical Units can be used reconfigurable consequential regions, the geometric bases for Shepard's (1987) theory of stimulus generalization in animals and humans. We derive from Shepard's (1987) generalization theory a particular multi-layer network with dynamic (centers and radii) spherical regions which possesses a specific mass function (Cauchy). This learning model generalizes the configural-cue network model (Gluck & Bower 1988): (1) configural cues can be learned and do not require pre-wiring the power-set of cues, (2) Consequential regions are continuous rather than discrete and (3) Competition amoungst receptive fields is shown to be increased by the global extent of a particular mass function (Cauchy). We compare other common mass functions (Gaussian; used in models of Moody & Darken; 1989, Krushke, 1990) or just standard backpropogation networks with hyperplane/logistic hidden units showing that neither fare as well as models of human generalization and learning. Given a favorable or unfavorable consequence, what should an organism assume about the contingent stimuli?

Hollywood's Captain Kirk, 90-year-old William Shatner, blasted into space Wednesday in a convergence of science fiction and science reality, reaching the final frontier aboard a ship built by Jeff Bezos' Blue Origin company. The "Star Trek" hero and three fellow passengers hurtled to an estimated 66 miles (106 kilometers) over the West Texas desert in the fully automated capsule, then safely parachuted back to Earth in a flight that lasted just over 10 minutes. ""You have done something," an exhilarated Shatner told Bezos as he emerged from the capsule, the words spilling from him in a torrent. "What you have given me is the most profound experience." He added: "I hope I never recover from this." He said that going from the blue sky to the blackness of space was a moving experience that made him wonder, "Is that the way death is?" Shatner became the oldest person in space, eclipsing the previous record -- set by a passenger on a similar jaunt on a Bezos spaceship in July -- by eight years. The flight included about three minutes of weightlessness and a view of the curvature of the Earth. Sci-fi fans reveled in the opportunity to see the man best known as the stalwart Capt. James T. Kirk of the starship Enterprise boldly go where no star of American TV has gone before. "This is a pinch-me moment for all of us to see Capt.

VAN HORN, Texas (AP) -- Hollywood's Captain Kirk, 90-year-old William Shatner, blasted into space Wednesday in a convergence of science fiction and science reality, reaching the final frontier aboard a ship built by Jeff Bezos' Blue Origin company. The "Star Trek" hero and three fellow passengers hurtled to an estimated 66 miles (106 kilometers) over the West Texas desert in the fully automated capsule, then safely parachuted back to Earth in a flight that lasted just over 10 minutes. "You have done something," an exhilarated Shatner told Bezos as he emerged from the capsule, the words spilling from him in a torrent. "What you have given me is the most profound experience." He added: "I hope I never recover from this."

Hollywood's Captain Kirk, 90-year-old William Shatner, blasted into space Wednesday in a convergence of science fiction and science reality, reaching the final frontier on board a ship built by Jeff Bezos's Blue Origin company. The Star Trek hero became the oldest person to ride a rocket, eclipsing the previous record -- set by a passenger on a similar jaunt on a Bezos spaceship in July -- by eight years. Dressed in a royal blue flight suit, Shatner joined three fellow passengers, four to five decades younger, on board the fully automated capsule that took off from remote West Texas for an up-and-down flight scheduled to last just 10 minutes or so. The spaceship aimed for an altitude of 106 kilometres (66 miles), at the fringes of space, after which the capsule was set to parachute back to the desert floor. Sci-fi fans revelled in the opportunity to see the man best known as the stalwart Captain James T Kirk of the starship Enterprise boldly go where no star of American TV has gone before.

Whether it's down to our own hubris, the disastrous effects of unbridled wealth accumulation and social division, war, the climate crisis, plague, a space rock or perhaps unfriendly aliens – we'll one day be dust caught in cosmic winds, lost to an indifferent universe. On our pale blue dot, the remnants of once-great civilisations and vanished peoples that we unearth already show us that advanced development is no guarantee of perpetuity. In sci-fi, humanity's naive yearning to fight on despite this realisation often proves a point of curiosity – and sometimes inspiration – for alien species. This is front and centre of the Mass Effect trilogy of video games, in which our imminent annihilation is given form in the tendrils of creatures called Reapers: ancient, building-sized, alien-robot hybrids that wipe out most life in the Milky Way every 50,000 years. Originally released between 2007 and 2012, the games were reissued this year as Mass Effect Legendary Edition, an updated complete trilogy, and there's a compelling case that they are among the best sci-fi ever made.

Ranking the Mass Effect original trilogy characters probably seems impossible. The cast is so diverse and dynamic that everyone playing will find different characters who resonate with them more than others. I love Tali Zorah, the awkward, nerdy engineer who eventually matures into a woman capable of expressing herself beyond the envirosuit that hides her physical traits. You might love Zaeed, the gruff mercenary who is the very pinnacle of Renegade -- a role-playing alignment in-game that prioritizes getting the job done at any cost, no matter the moral consequences -- but still has the heart of a child when confronted with things like a toy claw game or his very first rifle. In this list, I'll be ranking characters based on how they're written, as opposed to focusing on my opinions. The best, most memorable characters are those with agency -- characters who influence the plot with their actions and decisions. In Mass Effect, some characters are definitely more impactful than others, and some are memorable for their traits and character arcs. Overwhelmed newcomers to Mass Effect Legendary Edition may want to use these rankings to see which characters may be more worth their time.

For years now, some of the best, wildest, most moving or revealing stories we've been telling ourselves have come not from books, movies or TV, but from video games. So we're running an occasional series, Reading The Game, in which we take a look at some of these games from a literary perspective. In the beginning, it was the Normandy that I fell for, not Mass Effect. If it hadn't been for the Normandy (gorgeous, sleek, the most advanced ship in the Alliance fleet and personal ride of Commander Shepard, star of the series), I might've just quit the newly remastered Legendary edition of the beloved trilogy after the first few hours. See, I did not like Mass Effect at all when I started playing.

Now that Mass Effect Legendary Edition, the remaster of BioWare's groundbreaking space trilogy, is out, the video game series likely to reach a whole lot of first-time players--especially considering the current drought in new game releases. You're in for an incredible RPG experience packed with adventure, gunfights, telekinesis, ethical quandaries, space politics, and romanceable aliens. In Mass Effect, your choices have real consequences on the story, and you should feel free to experiment accordingly. But here's one choice you absolutely shouldn't make: Do not, under any circumstances, play the protagonist as a guy. Look, there's nothing wrong with men. It's totally okay to be a man, and in most circumstances, it's perfectly okay to choose to play a male character in a video game when given multiple gender options.