{
  "export": {
    "source": "https://urth.darkrealm.vip/thread/urth/5624",
    "note": "Exported from an unofficial mirror of a public mailing list. Copyright in each message remains with the person who wrote it.  Email addresses are obscured as `user at host`, the form the original archive published. This file was rebuilt from parsed fields rather than retained headers, so it is faithful in content but not byte-exact.",
    "addresses": "obscured as 'user at host'"
  },
  "archive": "urth",
  "thread": {
    "id": 5624,
    "subject": "Silk vs. Cthulhu",
    "messages": 2,
    "voices": 2,
    "first": "2010-06-05T15:16:24+00:00",
    "last": "2010-06-05T16:27:38+00:00"
  },
  "messages": [
    {
      "message_id": "<784183.5910.qm@web81408.mail.mud.yahoo.com>",
      "from": {
        "name": "Stuart Hamm",
        "address": "hammstu at sbcglobal.net"
      },
      "date": "2010-06-05T15:16:24+00:00",
      "subject": "(urth) Silk vs. Cthulhu",
      "in_reply_to": null,
      "reply_link": null,
      "blocks": [
        {
          "kind": "text",
          "depth": 0,
          "text": "So today I found my car with it's \"Silk for Calde\" bumper sticker parked behind a car with a sticker that read \"Got Cthulhu?\"\nWhat are the odds??\n\n???????? ? ? \n\nSTUHAMM.COM\nFACEBOOK/STUARTHAMM\nmyspace.com/stuhamm\n\n? ?? "
        }
      ]
    },
    {
      "message_id": "<AANLkTinN3eNjokjuFQnHq-CdGMXD7HxwxHHODsED-PWW@mail.gmail.com>",
      "from": {
        "name": "Gwern Branwen",
        "address": "gwern0 at gmail.com"
      },
      "date": "2010-06-05T16:27:38+00:00",
      "subject": "(urth) Silk vs. Cthulhu",
      "in_reply_to": "<784183.5910.qm@web81408.mail.mud.yahoo.com>",
      "reply_link": "header",
      "blocks": [
        {
          "kind": "quote",
          "depth": 1,
          "text": "On Sat, Jun 5, 2010 at 11:16 AM, Stuart Hamm <hammstu at sbcglobal.net> wrote:\nSo today I found my car with it's \"Silk for Calde\" bumper sticker parked behind a car with a sticker that read \"Got Cthulhu?\"\nWhat are the odds?"
        },
        {
          "kind": "text",
          "depth": 0,
          "text": "Ooh! This sounds like a fun Fermi problem.*\n\nWe can use the Birthday Paradox to find out. One result in the\nWikipedia article is that\n\n'This is a result of the good approximation that an event with 1 in k\nprobability will have a 50% chance of occurring at least once if it is\nrepeated k ln 2 times.'**\n\nLet's assume you park once a day averaged over your lifetime and you\nstart driving at age 20; your life expectancy would be somewhere\naround >70, so that's 50 years * 365 days per year, so that's 18250\ndays, and one parking per day so 18250 parking incidents where you\ncould've noticed such a thing.\n\nLet's assume that there was a 50% chance of you ever seeing such an\noccurrence (you were somewhat lucky), so that we can say '18250 = k *\nln 2'. Then, '18250 / ln 2 = k', and a calculator says that k = 26329\nand so the odds are 1 in 26,329.\n\nOf course, this is only the odds of *you* seeing someone with a\nCthulhu sticker parked in front of you. You observe a Silk is Calde\nsticker every day, after all. For the rest of us, the odds are even\nworse since our observation would have to both stickers. So the odds\nfor us is probably more like 1/26,329 * 1/26,329. (For you, it's more\nlike 1 * 1/26,329 as explained previously.)\n\nIn an aside, there are 254 million cars in the US.\n(http://en.wikipedia.org/wiki/Passenger_vehicles_in_the_United_States)\n\n* http://en.wikipedia.org/wiki/Fermi_problem\n** http://en.wikipedia.org/wiki/Birthday_paradox#Approximation_of_number_of_people"
        },
        {
          "kind": "sig",
          "depth": 0,
          "text": "gwern"
        }
      ]
    }
  ]
}