\( J(x) = \sum_i \sqrt{\frac{1}{T}\sum_t (\sum_j x_{ij}\,\delta_j(t))^2} \)
\( R_i(x) = \sqrt{\frac{1}{T}\sum_t (\sum_j x_{ij}\,\delta_j(t))^2} \), \( J = \sum_i R_i(x) \)
LP surrogate: \( \tilde{J}(x) = \sum_{i,t} w_{it}\,\left|\sum_j x_{ij}\,\delta_j(t)\right| \)
Aggregate J = ...