  $\newcommand{\eps}{\varepsilon}$
  We observe that a $(1-\eps)$-approximation algorithm to Independent Set, that
works for any induced subgraph of the input graph, can be used, via a
polynomial time reduction, to provide a $(1+\eps)$-approximation to Vertex
Cover. This basic observation was made before, see [BHR11].
  As a consequence, we get a PTAS for VC for unweighted pseudo-disks, QQPTAS
for VC for unweighted axis-aligned rectangles in the plane, and QPTAS for MWVC
for weighted polygons in the plane. To the best of our knowledge all these
results are new.
