A random process differs from the deterministic processes dealt with in thepreceding chapters in that it cannot be accurately predicted mathematically even ifthe past time history is known. Such a process is most meaningfully described in
preceding chapters in that it cannot be accurately predicted mathematically even if
the past time history is known. Such a process is most meaningfully described in
statistical terms. The basic statistical characteristics are reviewed first, presuming
that the random process x(t) may represent loading of the structure or its response
