Simple Maths Help A Lot !!

  • 1. How to compute a Pearson correlation coefficient in MATLAB? The idea is based on a simple fact in math: for two standardized variables (0 mean and 1 std), the correlation is equivalent to their inner product. Thus, for two large sample matrices X and Y, the sample correlation matrix is R=X'Y/(n-1), where n is the number of samples. See my implementation in MATLAB File Exchange or OpenConnectome Project. See below for a brain connectome matrix at 4mm spatial resolution generated by using these codes:
  • Short-Time Fourier Transformation

  • 2. Look into Geometry of Cortical Surface: Gabrel Peyre.
  • Looking for Small Graphs ??

  • Here are the small graphs (or connectome matrices) from more than 1000 subjects of KFC project. Enjoy exploring them :)