Machine Learning: Difference between revisions

Line 139: Line 139:
Then <br>
Then <br>
<math>
<math>
\begin{alignat}{2}
\mathbf{v}^T \mathbf{K} \mathbf{v}= \mathbf{v}^T [\sum_j K_{ij}v_j]
\mathbf{v}^T \mathbf{K} \mathbf{v}&= \mathbf{v}^T [\sum_j K_{ij}v_j]\\
= \sum_i \sum_j v_{i}K_{ij}v_{j}
&= \sum_i \sum_j v_{i}K_{ij}v_{j}\\
= \sum_i \sum_j v_{i}\phi(\mathbf{x}^{(i)})^T\phi(\mathbf{x}^{(j)})v_{j}
&= \sum_i \sum_j v_{i}\phi(\mathbf{x}^{(i)})^T\phi(\mathbf{x}^{(j)})v_{j}\\
= \sum_i \sum_j v_{i} \sum_k \phi_k(\mathbf{x}^{(i)}) \phi_k(\mathbf{x}^{(j)})v_{j}
&= \sum_i \sum_j v_{i} \sum_k \phi_k(\mathbf{x}^{(i)}) \phi_k(\mathbf{x}^{(j)})v_{j}\\
= \sum_k \sum_i \sum_j v_{i} \phi_k(\mathbf{x}^{(i)}) \phi_k(\mathbf{x}^{(j)})v_{j}
&= \sum_k \sum_i \sum_j v_{i} \phi_k(\mathbf{x}^{(i)}) \phi_k(\mathbf{x}^{(j)})v_{j}\\
= \sum_k \sum_i  v_{i} \phi_k(\mathbf{x}^{(i)}) \sum_j \phi_k(\mathbf{x}^{(j)})v_{j}
&= \sum_k \sum_i  v_{i} \phi_k(\mathbf{x}^{(i)}) \sum_j \phi_k(\mathbf{x}^{(j)})v_{j}\\
= \sum_k (\sum_i  v_{i} \phi_k(\mathbf{x}^{(i)}))^2
&= \sum_k (\sum_i  v_{i} \phi_k(\mathbf{x}^{(i)}))^2\\
\geq 0
&\geq 0
\end{alignat}
</math>
</math>
}}
}}