code: @Nullable
      public static Boolean sampledToBoolean(@Nullable String sampled) {
          return sampled == null ? null : DO_SAMPLE_VALUE.equals(sampled);
      }
docs: Converts a sampled (String) value to its Boolean representation.
  <p/>
  Note: If this method is invoked with a null value, the returned value will also be null.
  
  @param sampled The original value
  @return The converted sampled value