[COVARIATE]
input={p_F}

DEFINITION:
gender = { type=categorical, 
           categories={F,M},
           P(gender=F)=p_F }

;---------------------------------------
[INDIVIDUAL]
input={k_pop, omega_k, gender, beta_F}
gender={type=categorical,categories={F,M}}

DEFINITION:
k = { distribution=lognormal,
      reference=k_pop,
      covariate=gender,
      coefficient={beta_F,0},
      sd=omega_k }

;---------------------------------------
[LONGITUDINAL]
input =  {k}

EQUATION:
f = exp(-k*t)
