/** @return 1/lamda, which is the expected value of the exponential distribution. */
 public jprime.variable.FloatingPointNumberVariable getOffTime() {
   jprime.variable.FloatingPointNumberVariable temp =
       (jprime.variable.FloatingPointNumberVariable)
           getAttributeByName(ModelNodeVariable.off_time());
   if (null != temp) return temp;
   return (jprime.variable.FloatingPointNumberVariable)
       this.getReplicatedNode().getAttributeByName(ModelNodeVariable.off_time());
 }