Using a new technique, Hb was estimated in a blood sample. The test was repeated for 10 times. The reports were : 9.5, 9.2, 9.4, 9.6, 9.7, 9.9, 10.2, 10.3, 10.5, 12.1. Accurate value of Hb was estimated by standard tests to be 10.2. The new technique has -