Threads Tagged with covariance Thread / Thread Starter Last Post Replies Views 1. The problem statement, all variables and given/known data Random vector Y = ' where ' = transpose mean = u and... Feb3-14 04:22 PM statdad 1 130 Calculus & Beyond Homework For a typical ridge regression (Tikhonov regression) problem of minimizing the residual: \chi^2 = || Ax - b ||^2... Jan24-14 10:48 AM vibe3 0 328 Linear & Abstract Algebra Hey guys. I am going through the PRM (risk manager) material and there is a sample question that is bugging me. The... Dec13-13 10:41 AM Phoeniyx 3 411 Set Theory, Logic, Probability, Statistics Consider a co-variance matrix A such that each element ai,j = E(Xi Xj) - E(Xi) E(Xj) where Xi,Xj are random variables.... Nov28-13 11:01 AM Stephen Tashi 2 510 Set Theory, Logic, Probability, Statistics I'm working on a problem that wants me to show that $$Cov(X,Y) = 0$$ and I am up to the point where I simplified it... Nov1-13 01:49 PM economicsnerd 1 391 Set Theory, Logic, Probability, Statistics 1. The problem statement, all variables and given/known data Suppose ##X,Y## are random variables and ##\varepsilon =... Nov1-13 12:28 PM Karnage1993 0 165 Calculus & Beyond Homework Find cov(Y,Z) where Y = 2X_1 - 3X_2 + 4X_3 and Z = X_1 + 2X_2 - X_3 Information given E(X_1) =4 E(X_2) = 9 ... Oct27-13 11:04 PM Ray Vickson 1 320 Calculus & Beyond Homework 1. The problem statement, all variables and given/known data Suppose that X1, X2, and X3 are independent random... Oct26-13 10:48 AM gajohnson 4 432 Calculus & Beyond Homework if X= (3, 5, 7) & Y = (2, 4, 1) What is the 3x3 covariance matrix for X & Y? Sep13-13 04:13 PM mathman 7 576 Linear & Abstract Algebra http://en.wikipedia.org/wiki/Covariance I read from the above link that- The sample covariance of N observations... Sep12-13 05:41 AM DUET 6 573 Linear & Abstract Algebra Let xij be the ith independently drawn observation (i=1,...,N) on the jth random variable (j=1,...,K). These... Sep7-13 12:39 PM UltrafastPED 1 481 Linear & Abstract Algebra Hi all, I know how to find covariance of 2 vectors and variance too. If covariance matrix is to be found of 3... Aug16-13 10:31 PM dexterdev 2 596 Set Theory, Logic, Probability, Statistics Hi all, I have a doubt regarding the physical significance of eigen vectors of the covariance matrix. I came to... Aug16-13 12:53 AM dexterdev 2 478 Set Theory, Logic, Probability, Statistics hi i read an article by S.carlip about quantum gravity, arXiv:gr-qc/0108040v1 , in this article carlip stated: why... Aug10-13 12:40 PM Bill_K 1 352 Special & General Relativity Bianchi Haggard Rovelli just posted a landmark paper showing that QSM rises automatically from the GR requirement of... Jun24-13 07:09 PM marcus 5 849 Beyond the Standard Model Hi, 1. The problem statement, all variables and given/known data A fair die is rolled n times. X denotes the number... Jun10-13 01:34 PM peripatein 20 628 Calculus & Beyond Homework Let X1 and Y1 be two random variables. We have Cov(X1,Y1) = 0. Does this extend to any transformation X2 = g(X1) and... May13-13 10:14 AM Stephen Tashi 2 360 Set Theory, Logic, Probability, Statistics 1. The problem statement, all variables and given/known data See figure attached 2. Relevant equations 3.... Mar12-13 04:11 PM jegues 5 406 Calculus & Beyond Homework So I'm trying to take the expectation of the covariance estimate. I'm stuck at this point. I know I have to... Feb25-13 10:00 PM chiro 2 551 Set Theory, Logic, Probability, Statistics Hello everybody, I’d like to present this math problem that I’ve trying to solve… This matter is important because... Feb4-13 05:22 AM GoodSpirit 0 441 Linear & Abstract Algebra Some experimental covariance curve for entangled photons gives abs(Cov(0)) less than 1. For example : Violation of... Dec26-12 03:52 PM mfb 3 445 Quantum Physics 1. The problem statement, all variables and given/known data Hi, I'm considering the following problem: there are x... Dec19-12 01:13 PM Ray Vickson 8 792 Calculus & Beyond Homework General covariance ( 1 2 3 ... Last) I am trying to understand what exactly general covariance states. As I understand general covariance appeared as... Dec18-12 01:52 AM haushofer 98 7,584 Special & General Relativity Is the Dirac Equation generally covariant and if not, what is the accepted version that is? For general coordinate... Nov27-12 03:38 AM Demystifier 16 1,777 Quantum Physics My question is: what does "manifest" Lorentz covariance means for a field theory, as opposed to simply Lorentz... Nov26-12 07:12 AM haushofer 10 1,642 High Energy, Nuclear, Particle Physics 1. Consider the random variables X,Y where X~B(1,p) and f(y|x=0) = 1/2 0