Machine Learning: Difference between revisions

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&= -\sum [(y^{(i)})x^{(i)} - g(\theta^t x^{(i)})x^{(i)}]\\
&= -\sum [(y^{(i)})x^{(i)} - g(\theta^t x^{(i)})x^{(i)}]\\
\implies \nabla^2_\theta J(\theta) &= \nabla_{\theta} -\sum [(y^{(i)})x^{(i)} - g(\theta^t x^{(i)})x^{(i)}]\\
\implies \nabla^2_\theta J(\theta) &= \nabla_{\theta} -\sum [(y^{(i)})x^{(i)} - g(\theta^t x^{(i)})x^{(i)}]\\
&= \sum g(\theta^t x^{(i)})(1-g(\theta^t x^{(i)})) x^{(i)} (x^{(i)})^T \quad
&= \sum (g(\theta^t x^{(i)}))(1-g(\theta^t x^{(i)})) x^{(i)} (x^{(i)})^T \quad
\end{aligned}
\end{aligned}
</math><br>
</math><br>