摘要: This paper reports on recent progress in the study of autonomous concept learning systems. In such systems, initial space hypotheses is considered as a first-order sentence, declarative bias, and can thus be derived from background knowledge concerning goal concept. It easy to show that simple derivation process generates language corresponding an unbiased version defined restricted instance description language. However, structure typical corresponds stronger restriction still. shown this semantically-motivated, tree-structured bias fact reduce size doubly-exponential singly-exponential number features. allows effective small examples.