Mammalian cell death after exposure to radiation after a dose D of radiation often follows the linear-quadratic model.
Create an XY table. Enter radiation doses into X and fraction survival into Y. After entering data, click Analyze, choose nonlinear regression, choose the panel of linear-quadratic equations, and choose Linear quadratic: Y is fraction surviving.
X: Dose of radiation
Y: Fraction of cells surviving
A: Coefficient for linear killing
B: Coefficient for quadratic killing