Write and for the expectation and empirical measure. A sufficient bracketing of a function class condition is that, for every , finitely many brackets cover , with measurable integrable endpoints and . The uniform strong law from finite L1 bracketing then gives
Here the observations are independent and identically distributed. For an uncountable class, one either assumes a measurable supremum, for example through a pointwise separable function class, or formulates the conclusion as a pathwise bound on a common probability-one event.
For the parameterized class, the Heine-Borel theorem makes compact. Put . A countable dense subset of gives the same supremum because of continuity, so is measurable. Define the modulus
The supremum is measurable by taking a countable dense subset of the compact set of admissible pairs. For each , uniform continuity on gives . Also , and . Thus the dominated convergence theorem gives .
Choose a finite net of radius in . The lower and upper envelopes of over each closed ball are measurable integrable function brackets; the same countable-dense-set argument applies within each such compact ball. Their widths are at most . They cover the whole class, so its bracketing of a function class condition follows. Moreover, dominated convergence shows that is continuous. Both empirical and population functions therefore have a supremum over a common countable dense parameter set. Applying the uniform strong law from finite L1 bracketing proves uniform almost-sure convergence over the entire compact parameter set, rather than merely convergence at each fixed parameter.
For the exponential family,
where and . Thus a weak sufficient condition is bounded on , almost surely, and integrability of under the sampling law. No positive lower bound on over the whole real line is required. Zeros off the sampling support are harmless: choose arbitrary finite versions of the log-densities on that common null set when applying the function-class theorem.
If the sampling law is , one convenient assumption is that is a compact subset of the interior of the finite domain of the cumulant function of an exponential family, and
On that interior, is continuous, hence bounded on . Finiteness of at for some implies , hence . The displayed integral gives the remaining integrability. If the observations come from an arbitrary unrelated law, assumptions on and alone cannot control that law's tails; the sampling-law integrability must then be stated explicitly.