Let us consider an information source that generates binary
sequences of length T.
A sequence is generated with (actual)
probability .
Example:For a memoryless source with . The
parameter , i.e. the probability of generating a 1, has a
value in the range [0,1]. If the sequence contains a
zeroes and b ones then .
is generated with (actual)
probability 
.
with 
. The
parameter 
, i.e. the probability of generating a 1, has a
value in the range [0,1]. If the sequence 
contains a
zeroes and b ones then 
.