| الوصف: |
We consider the online vector bin packing problem where $n$ items specified by $d$-dimensional vectors must be packed in the fewest number of identical $d$-dimensional bins. Azar et al. (STOC'13) showed that for any online algorithm $A$, there exist instances I, such that $A(I)$, the number of bins used by $A$ to pack $I$, is $\Omega(d/\log^2 d)$ times $OPT(I)$, the minimal number of bins to pack $I$. However in those instances, $OPT(I)$ was only $O(\log d)$, which left open the possibility of improved algorithms with better asymptotic competitive ratio when $OPT(I) \gg d$. We rule this out by showing that for any arbitrary function $q(\cdot)$ and any randomized online algorithm $A$, there exist instances $I$ such that $ E[A(I)] \geq c\cdot d/\log^3d \cdot OPT(I) + q(d)$, for some universal constant $c$. |
