Units of Entropy Hh measures the number of b-ary units of information Example 1. S=X1, 2, X33, p =1/3, gives H2(,=,)=log23+log23+log23 33 =log23≈1.585bits EXample 2. p1-p2=1/4, p3=1/2 gives )==log, 4+=log, 4+log, 2 4424 1. 5 bits 復大软件学院9 Units of Entropy • Hb measures the number of b-ary units of information. • Example 1. S={x1 ,x2 ,x3 }, pi=1/3, gives • Example 2. p1=p2=1/4, p3=1/2 gives log 3 1.585 bits log 3 3 1 log 3 3 1 log 3 3 1 ) 3 1 , 3 1 , 3 1 ( 2 2 2 2 2   H    1.5 bits log 2 2 1 log 4 4 1 log 4 4 1 ) 2 1 , 4 1 , 4 1 (2 2 2 2  H   