A Convex Relaxation Bound for Subgraph Isomorphism

Table 5

None of the upper bounds for the maximum clique size comes close to the trivial bound 𝐾=7 that is inherent in the reformulation of the largest common subgraph problem into the maximum clique problem. The clique bounds are computed for the equivalent maximum clique formulation of the same 1000 problems used in Table 4.

Bound	K/L	Mean bound	Min.	Max
𝑈𝐵1	7/15	66.00±3.32	53.31	74.55
𝑈𝐵2	7/15	44.06±3.88	30.69	54.34
𝑈𝐵3	7/15	40.09±2.80	32	54
𝑈𝐵4	7/15	52.55±0.19	52.50	54.50