It is shown that the uniform distance between the distribution function
FnK(h)F_n^K(h) of the usual kernel density estimator (based on an i.i.d. sample from an absolutely continuous law on
\mathbbR{\mathbb{R}}) with bandwidth
h and the empirical distribution function
F
n
satisfies an exponential inequality. This inequality is used to obtain sharp almost sure rates of convergence of
||FnK(hn)-Fn||¥\|F_n^K(h_n)-F_n\|_\infty under mild conditions on the range of bandwidths
h
n
, including the usual MISE-optimal choices. Another application is a Dvoretzky–Kiefer–Wolfowitz-type inequality for
||FnK(h)-F||¥\|F_n^{K}(h)-F\|_\infty , where
F is the true distribution function. The exponential bound is also applied to show that an adaptive estimator can be constructed
that efficiently estimates the true distribution function
F in sup-norm loss, and, at the same time, estimates the density of
F—if it exists (but without assuming it does)—at the best possible rate of convergence over Hölder-balls, again in sup-norm
loss.
Keywords Kernel density estimator - Exponential inequalities - Adaptive estimation - Sup-norm - Plug-in property
Mathematics Subject Classification (2000) Primary: 62G07 - Secondary: 60F05