s***1 发帖数: 49 | 1 K(x,y) = transpose(phi(x))*phi(y)
If I have a kernel: K(x,y) = (transpose(x)*y + 1)^3, and x and y are both 2-
d vectors.
What is the explicit mapping phi that mimics the kernel value above? | p*******n 发帖数: 4824 | 2
2-
【在 s***1 的大作中提到】 : K(x,y) = transpose(phi(x))*phi(y) : If I have a kernel: K(x,y) = (transpose(x)*y + 1)^3, and x and y are both 2- : d vectors. : What is the explicit mapping phi that mimics the kernel value above?
| p*******n 发帖数: 4824 | | s***1 发帖数: 49 | | K****n 发帖数: 5970 | 5 你用他写的phi(x),代入你的两个式子试试,看相不相等
【在 s***1 的大作中提到】 : what does this mean ?
| p*******n 发帖数: 4824 | 6 展开后从中间开始乘,然后把对角上相等的常量提取出来。
比如最中间两个分别是9x27和27x9的矩阵,相乘后就是(transpose(x)*y + 1)*I_{9x9}
,依次类推,我想大概上面那个解答对的可能性就很高
就是不知道有没有更简单的表达式 |
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