Kinetic nonlinear mixed-effects model fit by SAEM
Structural model:
d_parent/dt = - ((k1 * g * exp(-k1 * time) + k2 * (1 - g) * exp(-k2 *
           time)) / (g * exp(-k1 * time) + (1 - g) * exp(-k2 * time)))
           * parent
d_m1/dt = + f_parent_to_m1 * ((k1 * g * exp(-k1 * time) + k2 * (1 - g)
           * exp(-k2 * time)) / (g * exp(-k1 * time) + (1 - g) *
           exp(-k2 * time))) * parent - k_m1 * m1

Data:
509 observations of 2 variable(s) grouped in 15 datasets

Likelihood computed by importance sampling
   AIC  BIC logLik
  2692 2702  -1333

Fitted parameters:
                   estimate  lower upper
parent_0              1e+02 99.303 1e+02
k_m1                  2e-03  0.002 3e-03
f_parent_to_m1        5e-01  0.448 5e-01
k1                    4e-02  0.024 6e-02
k2                    2e-02  0.009 2e-02
g                     5e-01  0.381 6e-01
Var.parent_0          2e+00 -0.551 4e+00
Var.k_m1              2e-02 -0.151 2e-01
Var.f_parent_to_m1    8e-02  0.018 1e-01
Var.k1                5e-01  0.095 9e-01
Var.k2                6e-01  0.125 1e+00
Var.g                 7e-02 -0.245 4e-01
a.1                   3e+00  2.569 3e+00
SD.parent_0           1e+00  0.390 2e+00
SD.k_m1               1e-01 -0.478 8e-01
SD.f_parent_to_m1     3e-01  0.175 4e-01
SD.k1                 7e-01  0.422 1e+00
SD.k2                 8e-01  0.471 1e+00
SD.g                  3e-01 -0.326 9e-01