We compute the limiting distributions of the lengths of the longest monoton
e subsequences of random (signed) involutions with or without conditions on
the number of fixed points (and negated points) as the sizes of the involu
tions tend to infinity. The resulting distributions are, depending on the n
umber of fixed points, (1) the Tracy-Widom distributions for the largest ei
genvalues of random GOE, GUE, GSE matrices, (2) the normal distribution, or
(3) new classes of distributions which interpolate between pairs of the Tr
acy-Widom distributions. We also consider the second rows of the correspond
ing Young diagrams. In each case the convergence of moments is also shown.
The proof is based on the algebraic work of J. Baik and E. Rains in [7] whi
ch establishes a connection between the statistics of random involutions an
d a family of orthogonal polynomials, and an asymptotic analysis of the ort
hogonal polynomials which is obtained by extending the Riemann-Hilbert anal
ysis for the orthogonal polynomials by P Deift, K. Johansson, and Baik in [
3].