12.07.2015 Views

Course in Probability Theory

Course in Probability Theory

Course in Probability Theory

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

5 2 1 RANDOM VARIABLE . EXPECTATION. INDEPENDENCEwe have alsoCompare the <strong>in</strong>equalities .15 . If p > 0, (`(iXi ) < oc, then xp?7-1{iXI > x} = o(l) as x -± oo .Conversely, if xPJ' J I X I > x) = o(1), then ((IX I P - E) < oc for 0 < E < p .* 16 . For any d .f. and any a > 0, we have0 0f[F(x + a) - F(x)] dx = a .0017 . If F is a d .f. such that F(0-) = 0, thenThus if X is a positive r .v .,{1 - F(x)} dx =J ~x dF(x) < +oo .f/ 0 0then we havec` (X)_ I~ 3A{X > x} dx =fo000GJ'{X > x} dx .18 . Prove that f "0,,, l x i d F(x) < oc if and only if0F(x) dx < ocand000[1 - F(x)] dx < oo .*19 . If {X,} is a sequence of identically distributed r .v .'s with f<strong>in</strong>ite mean,then1lim - c`'{ max iX j I } = 0 .n fl I x) dx = °l'(X llr > v)rvr -1 dv,0 0fsubstitute and <strong>in</strong>vert the order of the repeated <strong>in</strong>tegrations .]

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!