
Recent Posts
Recent Comments
犰狳指挥官 on run firefox on a remote Linux… 犰狳指挥官 on [zz] Homebrew: ruby bad interp… FisherYu on 搬家到这里 cgao on test LaTeX Yunlong on test LaTeX Archives
Categories
Meta
Advertisements
The covariance matrix of random variables is an matrix that . The correlation matrix is the covariance matrix of standardized random variables . For any random variable , we have , where . So the covariance matrix is positivesemidefinite, since … Continue reading
What is the probability that the forth business day of the month is Thursday?(forget about the holidays on weekdays) This is like asking what is the probability that the first day of the month is Sat, Sun, or Monday. So … Continue reading