EXHIBIT 11(A) VIALOG Corporation Calculation of Shares Used in Determining Loss Per Share For the Three Months Ended March 31, 1998 and 1999 Three Months Ended March 31, ---------------------------- 1998 1999 --------- --------- Basic Loss Per Share - -------------------- Weighted average number of common shares outstanding 3,542,668 6,032,774 ========= ========= Three Months Ended March 31, ---------------------------- 1998 1999 --------- --------- Diluted Loss Per Share - ---------------------- Weighted average number of common shares outstanding 3,542,668 6,032,774 Common stock equivalents -- -- --------- --------- Total 3,542,668 6,032,774 ========= =========