#frobenius-norm

Question 1: Single choice

easyAI-checkedLinear Models & Regularization

For vectors, $\lVert\mathbf{w}\rVert^2 = \mathbf{w}^\top\mathbf{w}$ . Which expression equals the squared Frobenius norm $\lVert\mathbf{W}\rVert_F^2$ of a matrix $\mathbf{W}$ ?

$\det(\mathbf{W}^\top\mathbf{W})$ , the determinant1
$\mathbf{1}^\top\mathbf{W}\mathbf{1}$ , the sum of all entries2
$\lambda_{\max}(\mathbf{W}^\top\mathbf{W})$ , the largest eigenvalue3
$\operatorname{tr}(\mathbf{W}^\top\mathbf{W})$ , the trace4

Timed test