varieties: Central GC, Southern SY, Pandong PD and Yang’an LW. Our results visualised in section 8.6, figure 8.6 below show that, as expected, Central Sui was by far the most widely understood variety,
with intelligibility levels of over 90 in most areas. Speakers of Southern Sui in Libo county, however, generally understood less than 75 of the Central Sui text. Pandong dialect speakers did even worse, on
average understanding less than 50.
Comprehension of the Southern Sui test was mixed. Speakers living in SD Central and Southern Sui areas understood it well. Sui speakers from Pandong, Western and Eastern dialect areas did not
understand much more than 60. Pandong dialect showed low levels of intelligibility in most areas. Only two places understood more than 70: Jiaoli JL, also Pandong dialect area and Dujiang DJ,
Eastern. Finally, the Yang’an dialect test only showed high intelligibility over 80 in geographical regions close to Yang’an, presumably due to acquired intelligibility see section 8.2 below. Speakers of
Pandong, Eastern and Southern dialects mostly only achieved scores of around 50 or lower on the Yang’an test.
These results confirm that inherent intelligibility among the Sui dialects is mixed and generally not as high as Sui scholars had previously thought. Central Sui is the most widely understood variety and is
thus an excellent lect on which to base a standard. However, Sui speakers living in Duyun municipality Pandong dialect area and Libo county Southern Sui area appear to struggle with the standard lect and
may need materials in their own dialects.
Our results come with the caveat that they only estimate levels of “initial contact intelligibility”. The fact that Sui dialects are very closely related genetically with the exception, perhaps, of Yang’an
dialect suggests that cross-dialectal intelligibility could be acquired fairly quickly. The authors’ own observations of Southern Sui speakers learning to communicate with Central and Western Sui speakers
confirms this hypothesis. An interesting avenue for further research would be to test rates of acquisition of some dialects compared to others. Such a measure might give a more accurate picture of inter-dialect
relatedness than a simple measure of initial contact intelligibility.
8.2 Measuring intelligibility
Intelligibility is a tricky concept and measuring it poses huge challenges. Mutual intelligibility between two different speech varieties is mainly influenced by two factors: 1 inherent linguistic similarity i.e.,
speakers of two dialects can understand each other because the two dialects share many linguistic features such as lexicon, pronunciation, grammatical structures and so on; 2 inter-dialect contact i.e.,
mutual intelligibility is acquired through high levels of exposure to the other dialect. For example, if someone from Yunnan travels to Sichuan, he may find that he can immediately understand most of the
local dialect of Chinese. This is because Yunnanese and Sichuanese are both varieties of Southwestern Mandarin and share many linguistic features such as tone contour, pronunciation and lexicon. This type
of intelligibility could be described as “inherent intelligibility”. On the other hand, if someone from Yunnan travels to Guangdong, she may find that she cannot understand the local dialect of Chinese in
this case, Cantonese at all. After living in Guangdong for a year or two, however, she may be able to understand Cantonese to a high degree. This type of intelligibility could be described as “acquired
intelligibility”. Regular exposure to Cantonese over a long period of time has allowed her to “learn” it. This type of intelligibility is not particularly due to any inherent linguistic similarity between Yunnanese
and Cantonese.
In reality, of course, such a clear line cannot be drawn between these two “types” of intelligibility. To some extent, comprehension of other dialects must always be acquired. Indeed, even two people
speaking the same dialect with the same accent sometimes falter in initial communication because of the peculiarities of their respective idiolects. Greater levels of comprehension are achieved viz. “acquired”
with effort over time. Furthermore, even if two dialects are closely related genetically, they may show low levels of intelligibility upon initial contact due to wildly differing phonetic features i.e., the “heavy
accent” of one dialect hinders speakers of another from understanding it. But the rate of acquisition will probably be much higher for two closely related dialects than for two dialects which are genetically
more distant.
Extra-linguistic factors such as attitudes towards speakers of another dialect can also play an important role in intelligibility Wolff 1959, Schüppert and Gooskens 2010. If people are motivated to
understand another dialect, they may understand a great deal; if they are not motivated at all, they may understand very little.
Levels of inter-dialect contact are very difficult to measure because of the complex social networks involved. Speaker attitudes and motivations are even more unquantifiable. Therefore most dialect
intelligibility studies have sought to isolate and measure inherent intelligibility. The same is true for this study.
8.3 The history of intelligibility testing
