Tsahi Levent-Levi at the TMC Talking Video blog refers to my recent post on video in which he says:
Andrew MacDonald tried to see what’s his perceived audio quality threshold. He shows that improving audio quality improves the medium and the cues it provides.
Ok, no problem. Many years of research bear this out. Audio quality has a direct impact on the effectiveness of interactions. But then Tsahi takes a leap:
Video adds visual cues which are not available in voice calls. And high definition video gives more visual cues than its SD counterpart.
This is where the research does not support Tsahi’s assertion. Video can add visual cues, but not the ones people expect and assume. Further, audio provides more non-verbal cues than is usually assumed.
Ten years ago, Steve Whittaker at ATT research looked at research going back many years prior to that, and found:
We first evaluate evidence for the utility of providing non-verbal communication information using video. We conclude that previous work has overestimated the importance of supplying non-verbal information at the expense of speech.
And nothing has changed today. There is still way too much assumed about the value of non-verbal communication potential in video. People put way too much focus on this and, therefore, neglect other, much more effective, uses of video, such as for presence, shared context, and its role in facilitating opportunistic interactions.
Furthermore, while we often overestimate the value of video providing non-verbal cues, we also tend to under-estimate the degree to which audio provides non-verbal cues. Other research cited in the above paper has shown this to be true as well:
The research (Chapanis) compared two media conditions: audio only communication, and high quality video/audio. If video does indeed provide useful cognitive cues, then there should be benefits for providing visual information in these types of collaborative problem solving tasks, where it is important to track the understanding and attention of remote participants. However, the studies showed that adding visual information did not increase the efficiency of problem solving, or produce higher quality problem solving.
We humans tend to assume that video must provided these non-verbal cues. It’s so intuitive and obvious. But when one looks at it objectively, again and again, the data proves otherwise.
It’s easy to say video does provide such cues, casually. No one would question it, unless they’ve looked at the years and years of research.
We should note that Mr. Levent-Levi works at RADVISION, a company that makes video-conferencing products. They need to go where the money is – and that’s in people beating the 20-year long dead horse of “talking heads” video as a substitute for face to face meetings – not in far more effective, but less sexy, uses of video.
Mr Blog,
Thanks for the thoughtful post.
I first want to state that video without good audio isn’t worth a thing – video is supplementary on top of audio.
I also would like to state that I have never hidden the fact that I am a RADVISION employee (for the last 10 years).
That said, I can only state things out of my own personal experience:
* I tend to find video calling useful
* I wouldn’t replace ALL of my voice calls with video calls, but I will replace some of them, depending on the situation.
* I wouldn’t replace all face-to-face meetings with video – I have made that clear already in the same post you quote me from.
I agree with you on most accounts, but I do believe that video will gain a lot of ground in the next 2 years – a lot more than in the previous 10.
Tsahi Levent-Levi
RADVISION
Thanks Tsahi.
More people will agree with you than me, so you’re in the majority. 🙂
To your one comment, that “video without good audio isn’t worth a thing” I agree in the context of a “video call” but I will also say that there are some very interesting uses of video alone (with no audio at all), such as always-on streams for presence awareness, shared context, to support opportunistic collaboration and spontaneous (unplanned) interaction etc. These uses of video without any audio have proven to be of more benefit than “video calls” but are rarely used because it isn’t as “sexy” – conventional wisdom says “video calls” are the “proper” use of video.
I’m happy that you find “video calls” useful – I don’t – and neither does objective research – but as I state, that’s okay, as your view is much more accepted than mine. 🙂