An Empirical Study on Ambiguous Words in Software Requirements Specifications of Local Government and Library Systems

Ambiguous words in software requirements specifications (SRSs) can cause serious misunderstanding, confusion and/or troubles between software purchasers and developers due to differences in interpretation of the words. This paper quantitatively analyzes existing SRSs to clarify (1) how many ambiguous words are actually included in SRSs and (2) how many these words require correction. This paper targets the Request For Proposals (RFPs), which describes initial requirements, of ten local government systems and ten library systems in Japan. As candidates of ambigous words, we analyzed ten Japanese words: (1) Ippanteki (common, commonly used, widely used), (2) Juudai (serious, seriously, critical, severe), (3) Juubun (sufficient, sufficiently), (4) Tekido (adequate, adequately, appropriate, reasonable), (5) Kouritsuteki (efficient, efficiently), (6) Juuyou (important), (7) Shunji (immediate, immediately), (8) Sugu (im-mediate, immediately), (9) Sokuji (immediate, immediately) and (10) Tadachi (immediate, immediately). As a result of the analysis, we found that among ten words, juubunnna (sufficient) was most frequently appeared in SRSs, and 43% of cases required correction when this word appeared. In addition, we also found that the number of ambiguous words varied greatly among the SRSs, and that larger SRSs did not necessarily contain more ambiguous words.