Abstract
The main purpose of the present work is to establish the functional asymptotic normality of a class of kernel conditional mode estimates when functional stationary ergodic data are considered. More precisely, consider a random variable (X,Z) taking values in some semi-metric abstract space E × F. For a real function φ defined on F and for each x ∈ E, we consider the conditional mode, say ⊝φ(x), of the real random variable φ(Z) given the event “X = x”. While estimating the conditional mode function by Θ̂φ,n(x), using the kernel-type estimator, we establish the limiting law of the family of processes {Θ̂φ(x) - Θφ(x)} (suitably normalized) over Vapnik–Chervonenkis class C of functions φ. Beyond ergodicity, no other assumption is imposed on the data. This paper extends the scope of some previous results established under mixing condition for a fixed function φ. From this result, the asymptotic normality of a class of predictors is derived and confidence bands are constructed. Finally, a general notion of bootstrapped conditional mode constructed by exchangeably weighting samples is presented. The usefulness of this result will be illustrated in the construction of confidence bands.
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Bouzebda, S., Chaouch, M. & Laïb, N. Limiting law results for a class of conditional mode estimates for functional stationary ergodic data. Math. Meth. Stat. 25, 168–195 (2016). https://doi.org/10.3103/S1066530716030029
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DOI: https://doi.org/10.3103/S1066530716030029
Keywords
- conditional mode estimation
- uniform entropy integral
- ergodic processes
- functional data
- martingale difference array
- strong consistency
- VC-class
- uniform CLT
- resampling