  We propose a new vertex formalism, called anti-refined topological vertex
(anti-vertex for short), to compute the generalized topological string
amplitude, which gives rise to the supergroup gauge theory partition function.
We show the one-to-many correspondence between the gauge theory and the
Calabi--Yau geometry, which is peculiar to the supergroup theory, and the
relation between the ordinary vertex formalism and the vertex/anti-vertex
formalism through the analytic continuation.
