  The shifted Schur measure introduced by Tracy and Widom is a measure on the
set of all strict partitions, which is defined by Schur $Q$-functions. The main
aim of this paper is to calculate the correlation function of this measure,
which is given by a pfaffian. As an application, we prove that a limit
distribution of $\lambda_j$'s with respect to a shifted version of the
Plancherel measure for symmetric groups is identical with the corresponding
distribution of the original Plancherel measure. Further we give expressions of
the mean value and the variance of the size of a partition with respect to the
measure defined by Hall-Littlewood functions.
