tailieunhanh - Báo cáo khoa học: "Ordering Prenominal Modifiers with a Reranking Approach"

In this work, we present a novel approach to the generation task of ordering prenominal modifiers. We take a maximum entropy reranking approach to the problem which admits arbitrary features on a permutation of modifiers, exploiting hundreds of thousands of features in total. We compare our error rates to the state-of-the-art and to a strong Google ngram count baseline. We attain a maximum error reduction of and average error reduction across all test sets of compared to the state-of-the-art and a maximum error reduction of and average error reduction across all test sets of compared. | Ordering Prenominal Modifiers with a Reranking Approach Jenny Liu Mit Csail Aria Haghighi MIT CSAIL jyliu@ me@ Abstract In this work we present a novel approach to the generation task of ordering prenomi-nal modifiers. We take a maximum entropy reranking approach to the problem which admits arbitrary features on a permutation of modifiers exploiting hundreds of thousands of features in total. We compare our error rates to the state-of-the-art and to a strong Google ngram count baseline. We attain a maximum error reduction of and average error reduction across all test sets of compared to the state-of-the-art and a maximum error reduction of and average error reduction across all test sets of compared to our Google n-gram count baseline. 1 Introduction Speakers rarely have difficulty correctly ordering modifiers such as adjectives adverbs or gerunds when describing some noun. The phrase beautiful blue Macedonian vase sounds very natural whereas changing the modifier ordering to blue Macedonian beautiful vase is awkward see Table 1 for more examples . In this work we consider the task of ordering an unordered set of prenomi-nal modifiers so that they sound fluent to native language speakers. This is an important task for natural language generation systems. Much linguistic research has investigated the semantic constraints behind prenominal modifier orderings. One common line of research suggests that modifiers can be organized by the underlying semantic property they describe and that there is a. the vegetarian French lawyer b. the French vegetarian lawyer a. the beautiful small black purse b. the beautiful black small purse c. the small beautiful black purse d. the small black beautiful purse Table 1 Examples of restrictions on modifier orderings from Teodorescu 2006 . The most natural sounding ordering is in bold followed by other possibilities that may only be appropriate in certain situations. an ordering on semantic .