Weighted Least Squares: an introduction

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  • เผยแพร่เมื่อ 4 ธ.ค. 2024

ความคิดเห็น • 23

  • @Gamabunta24345
    @Gamabunta24345 5 ปีที่แล้ว +4

    I keep coming back to your videos for so many of my classes. Thank you so much for having them! Huge help!

  • @indrajeetjaveri3
    @indrajeetjaveri3 4 ปีที่แล้ว +2

    7:21 That was such an amazing intuitive(geometric) explanation of how exactly OLS & WLS differ fundamentally and you did it without first telling any math or stats behind it. Now looking at the math behind it would be so much easier knowing this. This reminds me of Grant Sanderson from 3Blue1Brown. Even he does intuitive explanations first and maths later. Thank you so much for this and please posting more such videos!

  • @jakobforslin6301
    @jakobforslin6301 2 ปีที่แล้ว

    You deserve a medal!

  • @SpartacanUsuals
    @SpartacanUsuals  11 ปีที่แล้ว +3

    Glad to hear you liked it! If you have any ideas for further videos then please let me know. Thanks, Ben

  • @programacaosimples
    @programacaosimples 4 ปีที่แล้ว +1

    You are a great inspiration for me Ben! I love econometrics and the simple way you teach people. I am currently trying to teach how to perform econometrics in R for portuguese speakers, but, unfortunately, this is not a very popular topic in YT 😅

  • @samirasahly6703
    @samirasahly6703 ปีที่แล้ว

    Thanks for the explanation

  • @cihangwang8044
    @cihangwang8044 ปีที่แล้ว

    Amazing explanation.

  • @tsunetasora
    @tsunetasora 3 ปีที่แล้ว

    Thank you my midterm savior ^u^

  • @Ana230509
    @Ana230509 8 ปีที่แล้ว +2

    If you Please can you put an example with concrete values?
    Thanks

  • @TheDefaulterror
    @TheDefaulterror 11 ปีที่แล้ว

    This is my first youtube comment ever! Good job! Your tutorial video has been very helpful to me! Please keep it up!

  • @xinking2644
    @xinking2644 2 ปีที่แล้ว +1

    GOOD EXPALIN! thanks for your brilliant job, it really helps a lot =)

  • @SJ-hz7iu
    @SJ-hz7iu 10 ปีที่แล้ว +3

    Nice tutorial.If my suggestion worth noting then please kindly mark some key words in the side of the video so that the viewers can get them correctly. Since english is not my native language it was a bit difficult to catch few key words in the beginning of the video, especially at the description of GLS. May be this can be helpful to all others as well.. But still it helped for what I was looking for..Thank you..

    • @SpartacanUsuals
      @SpartacanUsuals  10 ปีที่แล้ว +8

      Hi, thanks for your message. I do eventually want to try to transcribe these videos - it may take me some time, but I think it would certainly be useful. Best, Ben

    • @rolandleudjou7040
      @rolandleudjou7040 9 ปีที่แล้ว

      Shital Joshi! you are right. I am french-speaking. I appreciate very well all Ben's videos. These help me understand many concepts in Econometrics. I have downloaded all. If transcripts exist I think I will be a master in Econometrics. Thank you, Ben!!

  • @xintongliu7968
    @xintongliu7968 6 ปีที่แล้ว

    Very clear! Thank you!

  • @pablohernandezgomez531
    @pablohernandezgomez531 5 ปีที่แล้ว

    I love you. We all do!

  • @sum1sw
    @sum1sw 4 ปีที่แล้ว

    Oh man. I'm sorry, but you lost me from the very beginning, but I still gave you a like. What I am interested in is, given a set of observations (Xobs, YObs), and estimated error in X and Y, usually called Sigma,x and Sigma,y. I want to arrive at a calculated set of Xcalc and Ycalc. If all my Sigma's are equal, I want to take an orthogonal line from each observation, find the intersection point with the curve (calculated from the initial estimates of alpha and beta). This gives me Xcalc and Ycalc, I can then proceed to minimize (Xobs-Xcalc)^2/Simga,x^2 + (Yobs-Ycalc)^2/Sigma,Y^2. As you can tell, I'm not talking about a straight line, I'm actually talking about a multivariable implicit function f(x,y,x) = 0. I figured out how to do it if all IF my sigmas are 1 (or equal). I'm trying to figure out how to implement the Sigmas in the calculation when they are NOT equal (or unity).
    I started out by linearising my the implicit equation using Taylor series around the point X0, Y0, Z0 which gives
    F(X,Y,Z) ~ f(X0, Y0, Z0) + dF/dX(X-X0) + dF/dY(Y-Y0) + dF/dZ(Z-Z0) Note that this is the equation of a plane, not a line.
    A line from the observed data point (Xobs, Yobs, Zobs), orthogonal to the plane, and in parametric form, is
    + t
    I can solve for t at the intersection point. But how do I adjust the slope of this line so I can take the errors (Sigmas in X, Y, and Z) into account ?
    That's my problem for today.

  • @ticklemedaly
    @ticklemedaly 11 ปีที่แล้ว +22

    Excellent tutorial! Perhaps labeling video numbers would aid in what video is next.

    • @SpartacanUsuals
      @SpartacanUsuals  11 ปีที่แล้ว +6

      Hi, many thanks for your message, and kind words. If you visit my youtube channel homepage you can find the videos ordered into playlists. Best, Ben

  • @tianshiliao5372
    @tianshiliao5372 6 ปีที่แล้ว

    Nice explanation, ty

  • @tOnmey
    @tOnmey 11 ปีที่แล้ว +1

    Nice tutorial

  • @EvaLaurenson
    @EvaLaurenson 11 ปีที่แล้ว +1

    very helpful

  • @duyuchilyang2091
    @duyuchilyang2091 5 ปีที่แล้ว

    Is this aitken gls?