Unbiased estimator revolutionizes active learning for optimal covariance matrix estimation.
The article explores a method to estimate covariance matrices when only some parts of the data are observed. By using a special type of random variable, the researchers developed an unbiased estimator for the covariance matrix and found a way to control the error in the estimation. They applied this method to a scenario where only a few variables are observed compared to the total number, and came up with a way to choose the best variables to observe for accurate estimation.