Accuracy of social judgements of observers watching business meetings
You may be interested in the research on "thin slices" of behavior, defined as a very short video clip of behavior, often without audio.

Abstract from Ambady &amp; Rosenthal (1992):


  A meta-analysis was conducted on the accuracy of predictions of
  various objective outcomes in the areas of clinical and social
  psychology from short observations of expressive behavior (under 5
  min). The overall effect size for the accuracy of predictions for 38
  different results was .39. Studies using longer periods of behavioral
  observation did not yield greater predictive accuracy; predictions
  based on observations under 0.5 min in length did not differ
  significantly from predictions based on 4- and 5-min observations. The
  type of behavioral channel (such as the face, speech, the body, tone
  of voice) on which the ratings were based was not related to the
  accuracy of predictions. Accuracy did not vary significantly between
  behaviors manipulated in a laboratory and more naturally occurring
  behavior. Last, effect sizes did not differ significantly for
  predictions in the areas of clinical psychology, social psychology,
  and the accuracy of detecting deception.


This methodology has been used frequently since this publication. I do not know the literature well enough to cite specifics, but perhaps this will point you in the right direction.


  Ambady, N., &amp; Rosenthal, R. (1992). Thin slices of expressive behavior
  as predictors of interpersonal consequences: A meta-analysis.
  Psychological Bulletin; Psychological Bulletin, 111(2), 256. PDF