A statistical study of quantifying magnetic complexity of solar active regions

Using more than 10 years of the synoptic charts constructed from the maps nearest central meridian, we collect a sample of 848 active regions. With the large sample of active regions, we analyze the distribution of the value of effective distance (dE) as a function of Mount Wilson Magnetic Classification (MWMC) and confirm the basic agreement between the value of dE and MWMC.