In S. Lee, J. Badler, and N. Badler. "Eyes alive," ACM Transactions on Graphics - Special Issue, Proceedings of SIGGRAPH 2002, San Antonio, TX, pp. 637-644, there were some formulas that unfortunately suffered from round-off error in the published version. Here are the equations as published and as corrected:

Eq. (4):

As published:
Y = 0.13X^6-3.16X^5+31.5X^4-155.87X^3+ 394X^2-465.95X+200.36,

Correction:
Y = 0.1251X^6-3.1619X^5+31.5032X^4-155.8713X^3+394.0271X^2-465.9513X+200.3621

Eq. (5) and (6):

As published:
The polynomial fitting function for mutual gaze duration is
Y = 0.0003X^2-0.18X+32,
and for gaze away duration is
Y=-0.0034X^3+0.23X^2-6.7X+79

Correction:
The polynomial fitting function for mutual gaze duration is
Y = c1*X^2 + c2*X + c3,
where c1=2.5524e-4, c2=-0.1763, and c3=32.2815,
and for gaze away duration is
Y = d1*X^4 + d2*X^3 + d3*X^2 + d4*X + d5,
where d1=1.8798e-5, d2=-0.0034, d3=0.2262, d4=-6.7021, and d5=78.831.