class_docstr: asymmetric mixed model of Tawn 1988
  
  special case:  k=0, theta in [0,1] : symmetric mixed model of
      Tiago de Oliveira 1980
  
  restrictions:
   - theta > 0
   - theta + 3*k > 0
   - theta + k <= 1
   - theta + 2*k <= 1
code: def _check_args(self, theta, k):
      condth = theta >= 0
      cond1 = (
          (theta + 3 * k > 0)
          and (theta + k <= 1)
          and (theta + 2 * k <= 1)
      )
      return condth & cond1
  
imports: import numpy
  from scipy import stats
  from statsmodels.tools.numdiff import _approx_fprime_cs_scalar, approx_hess
label_desc: Use image node_id 1 for calling the AsymMixed obj's underlying member method code with example usage: obj._check_args(theta, k) and returns: unknown