code: public boolean estimate() {
          final PersonVisitor visitor = new PersonVisitor();
          person.accept(visitor);
          if (visitor.hasDeathAttribute()) {
              // Death attribute found, we're out of here.
              return false;
          } else {
              final BirthDateEstimator bde = new BirthDateEstimator(person);
              final LocalDate date = bde.estimateBirthDate();
              if (date == null) {
                  // No death date and no birth date estimate, assume living.
                  return true;
              }
              final LocalDate today = provider.nowDate();
              final Period p = new Period(date, today);
              return p.getYears() < VERY_OLD_AGE;
          }
      }
docs: Tries to guess whether someone is living. If there is a death
  record, then no. If age (exact or estimated) is over 100, then
  no. Otherwise, yes.
  
  @return estimated living or dead