Skip to content
By using Twitter’s services you agree to our Cookies Use. We and our partners operate globally and use cookies, including for analytics, personalisation, and ads.
  • Home Home Home, current page.
  • About

Saved searches

  • Remove
  • In this conversation
    Verified accountProtected Tweets @
Suggested users
  • Verified accountProtected Tweets @
  • Verified accountProtected Tweets @
  • Language: English
    • Bahasa Indonesia
    • Bahasa Melayu
    • Català
    • Čeština
    • Dansk
    • Deutsch
    • English UK
    • Español
    • Filipino
    • Français
    • Hrvatski
    • Italiano
    • Magyar
    • Nederlands
    • Norsk
    • Polski
    • Português
    • Română
    • Slovenčina
    • Suomi
    • Svenska
    • Tiếng Việt
    • Türkçe
    • Ελληνικά
    • Български език
    • Русский
    • Српски
    • Українська мова
    • עִבְרִית
    • العربية
    • فارسی
    • मराठी
    • हिन्दी
    • বাংলা
    • ગુજરાતી
    • தமிழ்
    • ಕನ್ನಡ
    • ภาษาไทย
    • 한국어
    • 日本語
    • 简体中文
    • 繁體中文
  • Have an account? Log in
    Have an account?
    · Forgot password?
    New to Twitter?
    Sign up
drossbucket's profile
Lucy Keer
Lucy Keer
Lucy Keer
@drossbucket

Tweets

Lucy Keer

@drossbucket

Some crackpot. Interested in 'mathematical intuition', whatever that is.

Bristol, UK
drossbucket.wordpress.com
Joined June 2017

Tweets

  • © 2019 Twitter
  • About
  • Help Center
  • Terms
  • Privacy policy
  • Imprint
  • Cookies
  • Ads info
Dismiss
Previous
Next

Go to a person's profile

Saved searches

  • Remove
  • In this conversation
    Verified accountProtected Tweets @
Suggested users
  • Verified accountProtected Tweets @
  • Verified accountProtected Tweets @

Promote this Tweet

Block

  • Tweet with a location

    You can add location information to your Tweets, such as your city or precise location, from the web and via third-party applications. You always have the option to delete your Tweet location history. Learn more

    Your lists

    Create a new list

    Under 100 characters, optional
    Privacy

    Copy link to Tweet

    Embed this Tweet

    Embed this Video

    Add this Tweet to your website by copying the code below. Learn more

    Add this video to your website by copying the code below. Learn more

    Hmm, there was a problem reaching the server.

    By embedding Twitter content in your website or app, you are agreeing to the Twitter Developer Agreement and Developer Policy.

    Preview

    Why you're seeing this ad

    Log in to Twitter

    · Forgot password?
    Don't have an account? Sign up »

    Sign up for Twitter

    Not on Twitter? Sign up, tune into the things you care about, and get updates as they happen.

    Sign up
    Have an account? Log in »

    Two-way (sending and receiving) short codes:

    Country Code For customers of
    United States 40404 (any)
    Canada 21212 (any)
    United Kingdom 86444 Vodafone, Orange, 3, O2
    Brazil 40404 Nextel, TIM
    Haiti 40404 Digicel, Voila
    Ireland 51210 Vodafone, O2
    India 53000 Bharti Airtel, Videocon, Reliance
    Indonesia 89887 AXIS, 3, Telkomsel, Indosat, XL Axiata
    Italy 4880804 Wind
    3424486444 Vodafone
    » See SMS short codes for other countries

    Confirmation

     

    Welcome home!

    This timeline is where you’ll spend most of your time, getting instant updates about what matters to you.

    Tweets not working for you?

    Hover over the profile pic and click the Following button to unfollow any account.

    Say a lot with a little

    When you see a Tweet you love, tap the heart — it lets the person who wrote it know you shared the love.

    Spread the word

    The fastest way to share someone else’s Tweet with your followers is with a Retweet. Tap the icon to send it instantly.

    Join the conversation

    Add your thoughts about any Tweet with a Reply. Find a topic you’re passionate about, and jump right in.

    Learn the latest

    Get instant insight into what people are talking about now.

    Get more of what you love

    Follow more accounts to get instant updates about topics you care about.

    Find what's happening

    See the latest conversations about any topic instantly.

    Never miss a Moment

    Catch up instantly on the best stories happening as they unfold.

    1. Lucy Keer‏ @drossbucket Aug 3
      • Report Tweet

      Negative probability thread! (it's the tweet version of this blog post, as an experiment: https://drossbucket.wordpress.com/2019/08/01/negative-probability/ …)

      6 replies 52 retweets 181 likes
      Show this thread
    2. Lucy Keer‏ @drossbucket Aug 3
      • Report Tweet

      I'm not going to go too much into why people get interested in negative probabilities in the first place. For that (as for so many things) the best place to go is a blog post by @johncarlosbaez:https://johncarlosbaez.wordpress.com/2013/07/19/negative-probabilities/ …

      1 reply 0 retweets 9 likes
      Show this thread
    3. Lucy Keer‏ @drossbucket Aug 3
      • Report Tweet

      Instead I'm going to go through an example that shows *how* they work. I got this one from another excellent blog post, by @sigfpe: http://blog.sigfpe.com/2008/04/negative-probabilities.html … I like it because the numbers are nice and simple.

      1 reply 0 retweets 6 likes
      Show this thread
    4. Lucy Keer‏ @drossbucket Aug 3
      • Report Tweet

      So we have the following setup (from that post): "a machine produces boxes with (ordererd) pairs of bits in them, each bit viewable through its own door"

      1 reply 0 retweets 2 likes
      Show this thread
    5. Lucy Keer‏ @drossbucket Aug 3
      • Report Tweet

      Now we ask 3 questions: 1. Is the first box in state 0? 2. Is the second box in state 0? 3. Are the boxes both in the same state? Obviously these overlap: e.g. to be consistent, if you answered Y to 1. and N to 2., you'd also answer N to 3.

      1 reply 0 retweets 3 likes
      Show this thread
    6. Lucy Keer‏ @drossbucket Aug 3
      • Report Tweet

      So, for YNN, we learn that box 1 is definitely in state 0 and box 2 is definitely in state 1. We can represent this as the following probability distribution over possible pairs of states:pic.twitter.com/7XV6lwH2Cc

      1 reply 0 retweets 2 likes
      Show this thread
    7. Lucy Keer‏ @drossbucket Aug 3
      • Report Tweet

      OK, nothing very clever here! Now for an inconsistent set, NNN. Both boxes are in state 0, but... they're also in different states? Turns out you can still assign a 'probability' distribution. Sort of. Scare quotes because one 'probability' is negative:pic.twitter.com/P5v6tjbway

      2 replies 0 retweets 2 likes
      Show this thread
    8. David Chapman‏ @Meaningness Aug 3
      • Report Tweet
      Replying to @drossbucket

      Did you mean “both in state 1,” or do I need coffee?

      1 reply 0 retweets 0 likes
      Lucy Keer‏ @drossbucket Aug 3
      • Report Tweet
      Replying to @Meaningness

      Ugh! It's me that needs the coffee. I knew I'd mess up somewhere with lots of fiddly sign stuff like this!

      9:23 AM - 3 Aug 2019
      2 replies 0 retweets 0 likes
        1. Lucy Keer‏ @drossbucket Aug 3
          • Report Tweet
          Replying to @drossbucket @Meaningness

          Wish Twitter let you edit things

          0 replies 0 retweets 0 likes
          Thanks. Twitter will use this to make your timeline better. Undo
          Undo
        2. New conversation
        1. David Chapman‏ @Meaningness Aug 3
          • Report Tweet
          Replying to @drossbucket

          I think expositionally would be cleaner if the signs were flipped so Y=1, N=0. (I kept being confused by this. But I’m a computer guy.)

          1 reply 0 retweets 1 like
        2. Lucy Keer‏ @drossbucket Aug 3
          • Report Tweet
          Replying to @Meaningness

          Yeah, probably. There may have been some consistency reason for wanting it this way but I don't remember it now. I absolutely hate thinking about notation, it's the worst.

          0 replies 0 retweets 1 like
          3. End of conversation

      Loading seems to be taking a while.

      Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.

        Promoted Tweet

        false

        • © 2019 Twitter
        • About
        • Help Center
        • Terms
        • Privacy policy
        • Imprint
        • Cookies
        • Ads info