Measuring rhythm in PRAAT (%V) - what's a vowel interval?

[tom1san1]

The short version of my question is: what constitutes a vowel interval?

I know that to get %V I need to identify all the vowel intervals, sum them, then divide by total time of audio. But how do I know when a vowel interval starts and ends?

[tom1san1]

to answer my own question i just found this:
"C-interval = series of consonants between two vowels, V-interval = series of vowels between two consonants; across syllable and word boundaries, not across pause"

Here:Dellwo, V. O. L. K. E. R., FRANCISCO GUTIÉRREZ DÍEZ, and NURIA GAVALDÀ. "The development of measurable speech rhythm in Spanish Speakers of English." Actas del XI Simposio internacional de comunicación social, Santiago de Cuba. 2009.

Next question is...what constitutes a pause?

[MalFet]

I can't say that I've ever seen (or needed) a more phonetics-driven account of pauses than a simply intuitive one. Is there a reason "period of silence" doesn't work for you?

[tom1san1]

Yes, I'm measuring L2 speech which is full of periods of silence. The ref I found refers to word boundaries but broken L2 speech can sometimes stop mid-word (e.g. "accommo...dation" etc.).

I suppose I thought there might be a convention for this type of analysis, e.g. >0.2 seconds of silence is treated as a pause anything less is ignored. 

[MalFet]

If you're measuring as something as idiosyncratic as broken L2 speech, the conventions aren't going to work for you. If you're trying to describe some sort of prosody phenomenon, you'll have to be very clear about what you're trying to measure and them custom tailor your methodology to suit. Good luck!