In addition, as the skip-gram formulation in (4) is unidirectional (L(z ik | z jl ) =L(z jl | z ik )), we perform one-side optimization for the target sense z ik to stabilize model training 3 .
for the target word w i and the collocated word w j given respective contextsC t andC t (0 < |t − t | ≤ m), we first draw a sense z jl for w j from the policy π(• |C t ) and optimize the expected collocation likelihood for the target sense z ik as follows, Note that (4) can be merged into (5) as a single objective.