2 problems

Near-optimality conjecture. For all $r\in\mathbb{N}$, the $\ell_0$-penalised least-squares method should itself be nearly optimal in both the signal-strength condition and the loca…

For $0\leq r\leq k$, define … where $d\boldsymbol w=dw_1\cdots dw_k$, and $C_i(r)$ is the positively oriented circle of radius $1/2$ centered at $-1$ for $i\leq r$ and at $0$ other…