statistics

NumPy: calculate cumulative median

左心房为你撑大大i 提交于 2020-08-04 04:41:37
问题 I have sample with size = n. I want to calculate for each i: 1 <= i <= n median for sample[:i] in numpy. For example, I counted mean for each i: cummean = np.cumsum(sample) / np.arange(1, n + 1) Can I do something similar for the median without cycles and comprehension? 回答1: Here's an approach that replicates elements along rows to give us a 2D array. Then, we would fill the upper triangular region with a big number so that later on when we sort the array along each row, would basically sort

fisher's linear discriminant in Python

我怕爱的太早我们不能终老 提交于 2020-08-02 07:14:07
问题 I have the fisher's linear discriminant that i need to use it to reduce my examples A and B that are high dimensional matrices to simply 2D, that is exactly like LDA, each example has classes A and B, therefore if i was to have a third example they also have classes A and B, fourth, fifth and n examples would always have classes A and B, therefore i would like to separate them in a simple use of fisher's linear discriminant. Im pretty much new to machine learning, so i dont know how to

fisher's linear discriminant in Python

跟風遠走 提交于 2020-08-02 07:12:23
问题 I have the fisher's linear discriminant that i need to use it to reduce my examples A and B that are high dimensional matrices to simply 2D, that is exactly like LDA, each example has classes A and B, therefore if i was to have a third example they also have classes A and B, fourth, fifth and n examples would always have classes A and B, therefore i would like to separate them in a simple use of fisher's linear discriminant. Im pretty much new to machine learning, so i dont know how to

What does recall mean in Machine Learning?

放肆的年华 提交于 2020-07-31 06:55:22
问题 I know that the meaning of recall in search engine, but what's the meaning of recall of a classifier, e.g. bayes classifier? please give a an example, thanks. for example, the Precision = correct/correct+wrong docs for test data. how to understand recall? 回答1: Recall literally is how many of the true positives were recalled (found) , i.e. how many of the correct hits were also found. Precision (your formula is incorrect) is how many of the returned hits were true positive i.e. how many of the

What does recall mean in Machine Learning?

淺唱寂寞╮ 提交于 2020-07-31 06:55:06
问题 I know that the meaning of recall in search engine, but what's the meaning of recall of a classifier, e.g. bayes classifier? please give a an example, thanks. for example, the Precision = correct/correct+wrong docs for test data. how to understand recall? 回答1: Recall literally is how many of the true positives were recalled (found) , i.e. how many of the correct hits were also found. Precision (your formula is incorrect) is how many of the returned hits were true positive i.e. how many of the