Testing a generative model (software that produces text or other outputs) on every question in every (standard test set) is too costly. Evaluators often test different models on different subsets of questions, leaving a sparse, unpaired record: many scores are missing and responses do not line up question by question.
Product Kernel Perspective Space (PKPS) turns each model into a low-dimensional fingerprint built from its cached responses. It compares each response with responses to similar questions, not only identical ones, so it can use records that do not overlap.
PKPS matched sample scoring with up to eight times fewer queries, and combined with low-rank matrix completion, a missing-entry estimator, cut score-matrix completion error by up to 28 percent.
