Can the pinyin for 边 be either "biān" or "bian" in general?

Question

It looks like authors choose "biān" or "bian" as the pinyin for 边 haphazardly at dict.cn:

东边 = dōng biān
上边 = shàng biān
右边 = yòu bian
左边 = zuǒ biān
旁边 = páng biān
外边 = wài bian
一边 = yī biān
两边 = liǎng biān
那边 = nà biān
这边 = zhè biān
里边 = lǐ biān
天边 = tiān biān

(There's also 海边, 身边, 内边, and 谁边.) It likewise seems haphazard at xiaoma.info.

Question: Can the pinyin for 边 be either "biān" or "bian" in general?

This question basically generalizes How come the first tone in the character of 边 in the word 东边 is not written?. Maybe there's cases where "biān" xor "bian" is the only strictly correct pinyin (or pronunciation).

Answer 1

As I answered in another question you are referring to, those 边s should be pronounced as the first tone biān in standard mandarin except when 边 connotes 'positions' and 'directions', such as 里边 前边 东边 左边 这边 and 那边 in your list. Other than that, the rest are all first tone biān.

However, in spoken or daily usage, lots of people often pronounced it as neutral tone even for those that should be pronounced as first tone as dictionaries indicate.

The best way to get it correct all the time is to look up any authoritative dictionaries, such as 新华字典, 现代汉语词典 and etc. Some on-line dictionaries might not be right all the time because they are not well proofread. Usually, they just copy here and there.

Updates:

After I looked up in the latest dictionary 现代汉语词典， I have some updates on this answer above accordingly.

Answer 2

In 《现代汉语词典》, the 边 with possible neutral tone has only the following meaning: "方位词后缀" (suffix to location word).

Examples include 里边 前边 东边 左边.

In the words you listed, 旁边 一边 两边 天边 would not use the neutral tone. Not quite sure with 这边 and 那边, but I won't use neutral tone for them.

Answer 3

It's a dirty secret, but even with 'Standard Mandarin', there is no universal consensus on this. I checked two standard reference grammars (e.g. Modern Mandarin Chinese Grammar: A Practical Guide and Chinese: An Essential Grammar, both from Routledge), and examples use both tone diacritics and none.

It's a fact that northern Mandarin dialects tend to use more toneless elements in disyllabic compounds (e.g. 北边儿 běibianr) and southern Mandarin varieties tend use pronounce almost all syllables with tone (e.g. 北边 běibiān).

When I was living in Beijing, I mostly encountered toneless locative suffixes: 海滩上面 hǎitān shàngmian "on the beach," and, in Shanghai or Taipei, I encountered locatives suffixes with full tones: 海滩上面 hǎitān shàngmiàn "on the beach." Textbooks used at universities in Beijing, Shanghai, and Taipei are all inconsistent in usage.

Personally, I prefer the cadence of northern Mandarin.

Note: {r}-suffixation, or 儿化, doesn't seem to affect this.