© 2000 Todd Neller.  A.I.M.A. text figures © 1995 Prentice Hall.  Used by permission.
Normalization
•Write Bayes' Rule for P(M|S)
•Now write Bayes' Rule for P(ØM|S)
•We know P(M|S) + P(ØM|S) = 1
•Use these to write a new expression for P(S)
•Substitute this expression in Bayes' Rule for P(M|S)
•One does not need P(S) directly.