Excerpt from change request document:
An SIL-PNG survey (Kassell, MacKenzie and Potter 2005) found the three proposed languages were distinct from each other, using both lexicostatistical and intelligibility testing. Average lexical similarity of the three speech varieties is between 39% and 58%, as measured with a 170-item standard word list. The accepted threshold for regarding speech varieties as dialects of a single language is 70% lexical similarity (SIL 1991); these scores are well below that threshold. Testing of intelligibility found that speakers of each variety had 13 - 56% comprehension of recorded texts in the other varieties. SIL guidelines give a recorded text test score of 75% as the lowest acceptable indicator of comprehension; again these scores are well below that threshold. The survey team concluded that Andai, Nanubae and Tapei should be considered three distinct languages.