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La forma del problema Un directorio es una superficie: el miembro lo abre y adivina. Un recomendador es una superficie de empujar: el sistema propone y tiene que justificarse. La justificación es la parte difícil, y es donde vive la estadística. Tres restricciones hicieron esto distinto de un recomendador de contenido: El item es una persona con capacidad finita. Un hilo se le puede recomendar a diez mil personas. Un experto no. Una mala recomendación es cara de los dos lados. Quien pide desperdicia una petición, el experto desperdicia una hora, y los dos aprenden a ignorar la superficie. La afirmación tiene que ser checable. "Quizá te guste este hilo" no necesita evidencia. "Esta persona está un nivel adelante de ti en diseño de sistemas" sí. Recuperación: híbrida, fusionada con RRF Tres recuperadores independientes sobre el conjunto de expertos elegibles, fusionados con Reciprocal Rank Fusion: def rrf_fuse ( * ranked_lists , k = 60 ): """ Fusiona listas de ids rankeadas. El score depende solo del rank, nunca de la escala propia del recuperador, que es el punto: la similitud coseno y un conteo de hilos resueltos no son números comparables. """ fused = {} for lst in ranked_lists : for rank , key in enumerate ( lst ): fused [ key ] = fused . get ( key , 0.0 ) + 1.0 / ( k + rank ) return fused RRF es la primitiva correcta aquí por una razón que vale la pena decir: los recuperadores emiten cantidades incomparables. Uno regresa un coseno en [-1, 1] , uno regresa un conteo entero de hilos resueltos, uno regresa un delta de nivel de escalera. Normalizarlos a una escala común requiere supuestos sobre sus distribuciones que nadie tiene a este volumen de datos. RRF descarta las magnitudes y se queda solo con el orden, que es exactamente la información que sobrevive a una muestra chica. k = 60 es la constante estándar de la formulación original de Cormack et al. Aplana la cabeza: la diferencia entre el rank 1 y el rank 2 es 1/61 - 1/62 ≈ 0.00026 , así que un recuperador no pu

Electric-vehicle assistants rarely have just one job. A short Turkish question may ask for a nearby station, a charging-price comparison, help planning a route, or an explanation of battery health. Before an application can retrieve current data or generate an answer, it needs to identify that intent reliably. We created the Turkish EV Charging Intent Dataset as a small, transparent starting point for that routing problem. Version 1.0.0 contains 192 Turkish queries distributed evenly across eight intent classes. It is open under CC BY 4.0, includes fixed train, validation, and test splits, and is maintained by TekPedal , an EV charging map and vehicle decision platform for Türkiye. You can explore the dataset interactively , inspect the source and validation workflow on GitHub , or cite the permanent Zenodo release with DOI 10.5281/zenodo.22062688 . Why intent routing comes first An assistant should not answer every EV question in the same way. Different requests need different tools and freshness guarantees: a station request needs a map or location index; a price request needs current tariff data; route planning needs distance, range, and charging-stop logic; a battery question needs careful educational content; a vehicle comparison needs structured specifications. An intent router makes that separation explicit. It can send each query to the correct retrieval source, product page, or application workflow. This also makes evaluation easier: teams can test routing independently before measuring the quality of downstream answers. Dataset design The taxonomy contains eight balanced classes, with 24 records in each class: FIND_STATION COMPARE_PRICE ROUTE_PLANNING CHARGING_SPEED VEHICLE_COMPARISON HOME_CHARGING BATTERY_HEALTH OWNERSHIP_COST Every record includes a stable ID, the Turkish query, the intent identifier, a human-readable Turkish label, a suggested TekPedal content route, the assigned split, the language, and a provenance marker. Here is a simplified example

Enormous eruptions altered Earth’s climate and societies all over the globe.

How a tiny little electronic switch sparked the computer revolution.

Luxury water can contain different minerals and taste noticeably different. But a remote source, alkaline pH, and high price do not necessarily mean better hydration.

Hibernation cuts down on synapses, but mice seem to retain memories anyway.

Lands free of roads are under threat from the Trump administration’s proposed rollback.

Short version of a post on gex.live/research ; the full write-up, definitions and reproduce block live there. Most published dealer-gamma numbers are built from open interest : yesterday's outstanding contracts, multiplied by a convention about who holds which side. Whether the convention is right is a separate question. The prior question is simpler: how much of what trades today was already in that book this morning — and how much of tomorrow's book is being created today? Open interest and volume are enough to answer it, with no assumption about who bought. Sample: SPX and SPXW, 2022-04-14 to 2026-08-14, 1,081 trading days, every expiry within about a month (0DTE plus the 21 nearest), 8.6 million contract-days, 4.3 million with volume. Definitions Per contract (expiry, strike, right) and session D: OI(D) is open interest at the start of D, OI(D+1) at the start of the next session, ΔOI = OI(D+1) − OI(D) , vol the day's volume in that contract. |ΔOI| / vol is a lower bound on how one-sided the day's trading in that contract was — 1.0 means every lot opened (or every lot closed), 0 means opens and closes cancelled. Contracts expiring on D have no next-day OI and drop out of the ΔOI statistics; 4.1% of rows (3.8% of volume) show |ΔOI| > vol, which is impossible (OI snapshot timing) and are excluded. The book grows by 40% of what trades, every day days to expiry on D net ΔOI / volume |ΔOI| / volume (lower bound on one-sidedness) share of volume in contracts whose OI rose contract-days 1–5 37.8% 41.8% 90.3% 813,013 6–21 42.7% 53.3% 81.1% 2,206,446 22+ 42.8% 57.6% 76.5% 831,896 Across the whole book, net ΔOI is 39.9% of the day's volume on the median session (IQR 36.2–44.0%), positive in every year and every expiry bucket: the SPX book is always being built faster than it is unwound, until expiry does the unwinding. Far expiries are open-and-hold (a day's trading in a 22+ DTE contract is at least 58% one-sided); the nearest expiries churn (42% at 1–5 DTE). Per contract-

The LINK probe was supposed to use robotic arms to capture Swift and lift it into a safe orbit. Problems with its control system forced NASA to call off the attempt.

Thunderstorms make seismic waves that can be used to find sub-surface features.

A satellite dish left by previous owners may yet have something to offer today. Here's what it can and can't do.

Just weeks after Taylor Farms issued a recall of its iceberg lettuce amid a massive cyclospora outbreak, the Food and Drug Administration recalled more than one million eggs that may be contaminated with salmonella. The eggs, which come from Midwest Poultry Services, were distributed to Kroger and smaller grocery stores across the South and Southwest […]

Tesla has discontinued Solar Roof, its solar panels designed to look like regular roofing tiles, Electrek reports. Sources "close to the program" told the publication that Tesla has informed its third-party installer network that Solar Roof is no longer available to order, and that only conventional solar panels will be supplied going forward. While Tesla […]

“People have talked about the Colorado River crisis for decades—we’re now in it,” says one expert. “Everyone you talk to is like, ‘Shit, man.’”

Full walkthrough: https://www.youtube.com/watch?v=vFuFA3ByCs0 LeetCode 3116 — Kth Smallest Amount With Single Denomination Combination. Here’s the trick everyone misses: Brute force (generate all multiples, pick k-th) fails because k can reach 2×10⁹. The real approach: Binary search the answer X Count valid amounts ≤ X using inclusion-exclusion Odd subsets add, even subtract (bitmask over coins) LCM via GCD, break when LCM > X O(n · 2ⁿ · log(k·M)) — passes cleanly. The 26% acceptance rate makes this look harder than it is. Once you see the count(X) monotonic trick, it clicks.

In the current epoch of Artificial Intelligence, the industry remains singularly preoccupied with the "Model" — obsessing over the raw parameter scales of the latest LLMs or the specific benchmark performance of a new transformer variant. However, at Informatiqs, we shift the lens. We recognize that sustainable enterprise value is rarely derived from the model in isolation; instead, it emerges from the high-stakes architectural decisions and systemic orchestration that define its environment. As we launch our inaugural edition, we dissect a critical technological nexus: the convergence of Graph Neural Networks (GNNs), Generative AI, and the industrial-grade infrastructure of Google Cloud Platform (GCP). We argue that for complex enterprise datasets, the transition from flat vector embeddings in latent space toward non-Euclidean, graph-based relational intelligence is the primary differentiator for the next generation of resilient AI applications. 1. The Scientific Foundation: Exploiting Relational Inductive Bias Traditional Deep Learning architectures, such as Convolutional Neural Networks (CNNs) for images or Transformers for text, primarily operate on data structured as sequences (Euclidean space). While exceptionally powerful, these structures often fail to capture the topological nuances of real-world systems like supply chains, molecular structures, or fraudulent transaction webs where data is inherently non-Euclidean. Graph Neural Networks (GNNs) provide a framework for learning from data represented as nodes and edges. Unlike standard neural networks that process inputs in isolation, GNNs utilize a Message Passing paradigm. In this process, a node's internal representation is iteratively updated by aggregating information from its immediate neighbors. Instead of looking at a data point as a single row in a database, the GNN looks at who that data point "talks to" and how those connections define its identity. By utilizing Graph Attention mechanisms, we can fu

S301 passes close to Sagittarius A*—so close that its orbit could reveal how the black hole’s rotation warps the spacetime around it.

A small release, not a launch. The LAB tab on gex.live has a new rightmost rail called IDEA FEED . It is a stream of short, rule-shaped trading ideas about SPX dealer positioning — "fade the first touch of the call wall after a gap up", that kind of thing — collected daily by a scanner from what people actually discuss, rewritten into something the Lab compiler can parse, and published untested . That last word is the point. Why untested is the feature Every feed of trading ideas on the internet comes with a verdict attached: "this works", "78% win rate", a screenshot of a good month. The feed here refuses to do that. Each card says exactly two things about its idea: compiles clean (our compiler turned the text into a runnable rule without complaint) and untested (nobody has run it against the archive yet). The honest test is yours to run. One click drops the idea into the Lab conveyor. The compiler has already done the translation, so the first message in your session is the rule itself, stamped ↳ from IDEA FEED · compiles, untested . Running the backtest costs one Lab credit; a failed job refunds itself. If your balance is zero the button does not go dead — it turns into 0 CREDITS · BUY → , remembers the idea you picked, and comes back to it after. What you will not find No source attribution on the cards. The idea is the unit, not the poster. No win rates, no "rated", no thumbs. The archive is 1,000+ finished SPX sessions; the Lab tests against all of it with an out-of-sample split and tells you what survived, which so far is: very little. That verdict is worth more than a badge on a card. No approval gate. The scanner's finds ship directly every day, so the feed stays fresh by itself. "NEW" is personal — it means new since you last opened the rail, not new for everyone. Why build a feed that mostly produces "no" Because the alternative is pretending. The whole site is built on measuring dealer positioning from the tape instead of assuming it from yesterday's ope

gex.live has two halves. The terminal measures where SPX options dealers are positioned, every second, from the tape. The Lab is the half that asks the uncomfortable question: does any of that predict anything? What it is A browser-side conveyor with three stages and a credit meter. Compile. You describe a rule in plain text — "short the first touch of the put wall when net gamma is below the 20th percentile" — and the compiler turns it into a deterministic rule over the archive's fields: flip, walls, hold band, gamma percentile, DEX/VEX/vanna/charm per strike, time of day. Compiling is free. If the text is ambiguous the compiler says which part, instead of guessing. Backtest. The rule runs against the full session archive — 1,000+ finished SPX days, every one of them public at gex.live/sessions — with a fixed out-of-sample split. One credit per job; a job that fails refunds itself. Quant optimize. Optional. A LightGBM pass over the same feature store to see whether there is structure the hand-written rule missed, reported as out-of-sample AUC plus feature importance, not as a new "signal". The heavy part (DuckDB + LightGBM) runs in a scale-to-zero container that reads snapshots over HTTPS from the public archive. It depends on no machine and on no private data, which is the point: you are testing against the same files anyone can download. The honest-stats rule Every verdict comes with its baseline. "Your rule made 3% in-sample" means nothing next to "the unconditional drift over the same days was 2.8%". The report shows both, shows the out-of-sample half separately, and refuses to produce a headline number from the in-sample half. Most rules do not survive this. That includes our own: the site's own directional levels were tested three separate ways across the whole archive and none held out of sample — which is why the terminal sells measurement and not signals, and why the Lab exists at all. The free Idea Feed Next to the conveyor sits a rail of rule-shaped idea

The yeetcycling math resembles asteroid mining in reverse.