{
  "id": 19169342,
  "title": "The coin-flipping trick that counts the Internet",
  "url": "https://urgent.news/2026/11/09/the-coin-flipping-trick-that-counts-the-internet",
  "topic": "science",
  "section": "Science",
  "published": "2026-11-09T15:15:00.000Z",
  "source": {
    "name": "Scientific American",
    "slug": "scientific-american",
    "url": "https://www.scientificamerican.com/article/the-coin-flipping-trick-that-counts-the-internet/"
  },
  "original_language": "en",
  "account": "The HyperLogLog algorithm offers a clever solution for estimating the number of unique visitors to a website without requiring the memory needed to store a full list of unique IDs. Instead of counting every page view, the algorithm relies on visitors to \"flip coins\" as they browse, which are transformed into a string of 0s and 1s using a hash function. The site keeps track of the longest sequence of consecutive 0s observed among all visitors, which provides a close approximation of the total number of unique visitors. This simple approach allows websites to efficiently estimate audience size while using only a small amount of memory.",
  "summary": "Here’s how the ubiquitous HyperLogLog algorithm works",
  "key_points": [
    "HyperLogLog algorithm estimates unique visitors without full list of IDs",
    "Visitors flip coins, hash function transforms flips into 0s and 1s",
    "Longest sequence of consecutive 0s approximates total unique visitors"
  ],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}