Commonly used evaluation measures including Recall, Precision, F-Measure and Rand Accuracy are biased and should not be used without clear understanding of the biases, and corresponding identification of chance or base case levels of the statistic. Using these measures a system that performs worse in the objective sense of Informedness, can appear to perform better under any of these commonly used measures. We discuss several concepts and measures that reflect the probability that prediction is informed versus chance. Informedness and introduce Markedness as a dual measure for the probability that prediction is marked versus chance. Finally we demonstrate elegant connections between the concepts of Informedness, Markedness, Correlation and Significance as well as their intuitive relationships with Recall and Precision, and outline the extension from the dichotomous case to the general multi-class case.
Physicists may have just cracked open a hidden side of the quantum world。 For decades, every known particle was thought to belong to one of two categories — bosons or fermions — but researchers have now shown that bizarre “in-between” particles called anyons could also exist in a one-dimensional system。 Even more exciting, these strange particles m
Scientists have pulled off a mind-bending quantum experiment that sounds almost impossible: they showed that tiny metal particles made of thousands of atoms can exist in multiple places at once。 Using advanced laser techniques, researchers at the University of Vienna observed quantum interference in sodium nanoparticles far larger than the kinds of
Astronomers using the James Webb Space Telescope have spotted something that shouldn’t exist—at least not so early in the universe。 A massive galaxy, formed less than 2 billion years after the Big Bang, appears to have no rotation at all, a trait usually seen only in much older, evolved galaxies。 This challenges current theories that young galaxies
A bizarre planetary pairing 190 light-years away is challenging everything astronomers thought they knew about how worlds form。 A “lonely” hot Jupiter — typically found without nearby companions — is sharing its system with a smaller mini-Neptune tucked even closer to the star, a setup once thought nearly impossible
Scientists have taken a major step toward ultra-secure quantum communication by demonstrating a remarkably stable quantum encryption system that worked across more than 120 kilometers of optical fiber。 Using tiny semiconductor quantum dots that emit single particles of light on demand, the team achieved one of the highest secure key rates yet for t
NASA’s Psyche spacecraft is about to pull off a dramatic close flyby of Mars, skimming just 2,800 miles above the planet to get a powerful gravitational boost on its journey to the mysterious metal-rich asteroid Psyche。 The maneuver will save propellant while giving mission scientists a rare chance to test and calibrate the spacecraft’s instruments
A mysterious comet from beyond our solar system is giving astronomers a rare glimpse into alien worlds — and it may have formed in a place far colder and stranger than anything around our Sun。 The interstellar visitor, called 3I/ATLAS, contains an astonishingly high amount of “heavy water,” far exceeding anything seen in our own solar system
NASA’s Curiosity rover had an unexpectedly stubborn Mars souvenir after drilling into a rock nicknamed “Atacama” — the entire chunk ripped loose from the ground and stayed stuck to the rover’s drill。 Engineers watched as Curiosity shook, vibrated, tilted, and spun the drill over several days in an effort to free the rock, while cameras captured the
Scientists are using sunlight to turn plastic waste into clean fuels like hydrogen, offering a breakthrough solution to both pollution and energy challenges。 While still in development, the approach could transform trash into a valuable resource for a low-carbon future
In a major breakthrough, scientists have experimentally confirmed a universal growth law in two dimensions using a quantum system of fleeting light–matter particles。 The finding strengthens the idea that wildly different processes—from crystals to living systems—may all follow the same hidden rules
Scientists may have found a powerful new way to hunt for alien life — not by searching for specific molecules, but by looking for hidden patterns in how those molecules are organized。 Researchers discovered that living systems leave behind a kind of chemical “fingerprint” in the statistical distribution of amino acids and fatty acids, one that cons
Cumberland, B。 is reimagining its coal mining past as a clean energy opportunity。 Water trapped in abandoned mine tunnels could be used in a geothermal system to heat and cool buildings efficiently and with minimal emissions
Creating complex molecules usually requires years of experience and countless decisions, but a new AI system is changing that。 Synthegy lets chemists guide synthesis and reaction planning using simple language, while powerful algorithms generate and evaluate possible solutions。 The AI doesn’t just compute—it reasons, scoring pathways and explaining