Verifiably

"Given the escalating house prices, it seems like a verifiably better decision to go with renting for longer," Ciuntu said.

Source: tatoeba (7767413)

Linguists recognize that Northern Berber dialects are verifiably mutually intelligible.

Source: tatoeba (11703010)

Near-synonyms: traceably, provably, confirmably

Source: wiktionary

Obviously, an absolute guarantee of optimality is not possible through this type of heuristic search, but the eventual stability achieved leads to an ultrametric that is usually very good (although not verifiably optimal). Throughout this discussion it is assumed that the subsets of objects for which separate optimal ultrametrics are generated, or the number of object classes to be used in obtaining an optimal ultrametric beginning from that point, are all of a size that could be handled optimally (i.e., some number in the lower teen’s).

Source: wiktionary