Recent content by Wenlong

  1. W

    How to calculate inverse cosine of two variables

    Hi, all I am looking into inverse cosine operations. I have a question like follows: Let x and y be two variables of degrees, how to separate equation arccos(x+y) into an equation that contains x and y separately? Such as arccos(x+y) = f1(...x) + f2(...y)? Thank you very much for your...
  2. W

    What is the difference between whitening and PCA?

    Hi, all I am looking into whitening transformation. According to the definition and explanation of Wikipedia, whitening transformation is a decorrelating process and it can be done by eigenvalue decomposition (EVD). As far as I know, EVD is one of the solutions of principal component analysis...
  3. W

    Does higher order moments means more attention to local area?

    Hi, Haruspex Thank you very much for your reply. It helps alot. Then may I ask a further question base on this? Take PCA and ICA (independent component analysis) for example, PCA compute principal components with covariance matrix (2nd order moment) while ICA compute independent components...
  4. W

    Does higher order moments means more attention to local area?

    Hi, Haruspex Thank you very much for your reply. It helps alot. Then may I ask a further question base on this? Take PCA and ICA (independent component analysis) for example, PCA compute principal components with covariance matrix (2nd order moment) while ICA compute independent components...
  5. W

    What does uncorrelatedness and independence imply?

    Hi, Lavinia Thank you very much for your reply, clear and easy to understand. Can I ask a further question base on this? Since I am looking into different analysis techniques, like PCA or ICA. I find that they are using different order moments to calculate the components. For PCA is 2nd...
  6. W

    Does higher order moments means more attention to local area?

    Dear all, Sorry to post this question in this section again. I am currently looking into few static analyse algorithms. I noticed that they are analysing with different order moments or cumulants to analyse the data. I guess it is because these algorithms are focus on different aspect of...
  7. W

    What does uncorrelatedness and independence imply?

    And, why independent is loftier than uncorrelated? In other words, what is the advantage of independence than uncorrelatedness? Thank you very much. Wenlong
  8. W

    What does uncorrelatedness and independence imply?

    Hi, Mathman Thank you very much for your reply. Actually, I'm using some statistical techniques to analysis the dataset (like Pricipal Component Analysis). Some of the technique result in a set of linearly uncorrelated vectors( basis), the others result in a set of statistical independent...
  9. W

    What does uncorrelatedness and independence imply?

    Dear all, I'm currently reading papers of statistical modelling. I encountered with the concepts of uncorrelatedness and independence. I understand the definitioins, but I am wondering what is the real effects they can make in statistical analysis? For example, I have a dataset and I use...
Back
Top