Returns weighted percentiles of a sample given the weight vector w ％ The idea is to give more emphasis in some examples of data as compared to ％ others by giving more weight. For example, we could give lower weights to ％ the outliers. ％ The motivation to write this function is to compute percentiles for Monte ％ Carlos simulations where some simulations are very bad (in terms of goodness ％ of fit between simulated and actual value) than the others and to give ％ the lower weights based on some goodness of fit criteria.
