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The meanings of various lengths of elapsed time do not vary widely from one person to another: Less than 1/3 sec is ‘instantaneous’, Less than l sec is ‘fast’ Less than 5 sec is a ‘pause’ and Greater than 10 sec is a ‘wait’. Time sharing interactions should be ‘instantaneous.’ Transaction interactions should be without ‘wait.’
in For Principles of Main Computer Dialog Computer Aided Design, Vol. 10, No. 3, pg 197, May 1978
