90% of the T Distribution

(entropicthoughts.com)

53 points | by ibobev 4 days ago

4 comments

  • snarkconjecture 12 hours ago
    Unless I'm mistaken, this uses "standard deviation" to refer to standard error throughout. They differ by a factor of sqrt(num_samples).

    This is actually much more commonly useful than the t distribution, in my experience. You can squint at a histogram (or some summary stats), eyeball the stdev, approximate the stderr in your head, and get a pretty good sense of confidence.

    I most often find myself doing this for the Bernoulli distribution, where it's also handy to know that the stdev is sqrt(p(1-p)), or "about 1/2 if p is middling, or sqrt(p) when it's small" (and you can flip the polarity to handle p→1).

  • kqr 9 hours ago
    Author here. It feels a bit pushy and uncharacteristic for me, but now that this ended up on the front page I would really appreciate if I could get 3.5 minutes out of your life, by taking this keyboard latency probe: https://xkqr.org/bellwether/keyboardtest.html

    I've already received very good data, but there are some tenuous connections that are still too noisy to be certain of

    - Are Apple keyboards really slower that non-Apple keyboards?

    - Are cheap keyboards really faster than expensive keyboards?

    - Are virtually all split keyboards programmable?

    More samples would help nail these things down. I'll share the analysis with the community once I'm done, of course. (The analysis pipeline is mostly automated so I can work on analysis in parallel with receiving more submissions.)

    • ranma42 7 hours ago
      How do you distinguish between input (Keyboard/USB) and output (Browser/Graphics stack) delays in this test?
      • kqr 7 hours ago
        That's outside the scope of what I wanted to find out so my plan was to treat that as part of the random effects varying from user to user.

        But now that you say it, I could annotate the data with a guess about OS and browser from the user agent string. Cool idea. Thanks!

        • zamadatix 4 hours ago
          It won't be very random though. E.g. Apple keyboards will almost always be on device with Apple's hardware & stack, cheap keyboards will tend to be with cheap computers/monitors, expensive keyboards the opposite.

          It'll still be interesting data (and I'll dump as many of my systems in as I can), but it will take a lot more than treating differences as noise to answer those kinds of questions in a meaningful way.

          • kqr 3 hours ago
            That is indeed an annoyance. Last time I looked at the data the "Apple keyboard" and "Apple computer" submissions overlapped so much I couldn't include them separately in the model.

            Similarly, I can't separate the effects of programmable and split keyboards because those two almost perfectly overlap in the data.

            I hope getting more submissions will help at least a little bit with this.

  • bvan 11 hours ago
    Not to be too picky, but I think when the author refers to ‘number of samples’, he means ‘sample size’. One sample, one or more observations.
  • Fraterkes 15 hours ago
    This is neither here nor there: I was reading the about page of the author, and it contains a passage that slightly confused me: "My name is Chris and I live in Sweden. I have a beautiful, supportive wife whose love I will never be able to requite, neither in degree nor kind." English isn't my first language, how should the second sentence be interpreted?
    • sohex 14 hours ago
      My interpretation would be that he feels his wife is incredibly loving in a quantity he isn’t able to match (degree) and in a unique way he’s not able to match (kind). General life experience plus the fact that he wrote that tells me he’s probably wrong and his wife would probably say the same about him, but that’s just speculation.
    • kryptiskt 14 hours ago
      That it's not possible for him to love her back as much as she does. "Requite" is quite an obscure word, I've only ever seen it used in the phrase "unrequited love", which means a love which isn't returned (in quite a different sense than what is used here, since I assume that the author didn't mean that he didn't love his wife, only that his love didn't measure up).
    • jedimastert 13 hours ago
      A kind of literal translation would be that he cannot match the amount of love and support that his wife shows, both in amount or in intensity.

      A rewording might be "she is more supportive than I could ever be, and better at being supportive than I could ever be"

    • krackers 14 hours ago
      Poetic way of saying that he is really thankful for her and is indebted to her (not in a literal monetary sense, just that her support and love is without bound, such that his own can never measure up against it).
    • markerz 14 hours ago
      I have a wife. I love my wife. My wife loves me. I cannot return my wife’s love for me at the same amount or manner. She loves me more than I can ever love her. She loves me in ways I can never.

      It’s very poetically written and sounds very loving. My simple translation loses a lot of beauty.

    • srean 9 hours ago
      To address the degree bit, one could bake a couple of pies once in a while.

      Let me show myself out.

      • kqr 9 hours ago
        This is good on many levels. It hits temperature degrees, angular degrees, and it's actually accurate advice.
        • srean 9 hours ago
          Was entirely tongue in cheek. A long time admirer of your blog.

          Having a wonderful wife myself I can understand the feelings.