On Fri, 4 Nov 2011, bonda wrote:

The 2006 CSDA paper is really very informative, perhaps, I'm trying to understand the things lying beyond. If we have e.g. k=3, then taking nproc=3 for the functional maxBB we get a critical value (boundary)

maxBB$computeCritval(0.05,nproc=3)
[1] 1.544421,

and this for nproc=NULL (Bonferroni approximation) will be

maxBB$computeCritval(0.05)
[1] 1.358099.

No. In the latter case no Bonferroni approximation is applied. If you want to use it, you can do so via the rule of thumb

R> maxBB$computeCritval(0.05/3, nproc = 1)
[1] 1.547175

which essentially matches the critical value computed for nproc = 3. If you use the more precise value 1 - (1 - 0.05)^(1/3) instead of 0.05/3, you get a match (up to some small numerical differences).

Setting nproc=NULL is only possible in efpFunctional():
efpFunctional() sets up the computeCritval() and computePval() functions via simulation methods (unless closed form solutions are supplied). For the simulation two strategies are available: Simulate nproc = 1, 2, 3, ... explicitly. Simulate only nproc = 1 and apply a Bonferroni correction. The last option is chosen if you set nproc=NULL -- it makes only sense if you aggregate via the maximum across the components.

The resulting computeCritval() and computePval() function always need to have the correct nproc supplied (i.e., nproc=NULL makes no sense).

Aggregating 3 Brownian bridges first over components, we obtain time series
process. Now, we wonder if maximum value of the process (aggregation over
time) lies over boundary. Which boundary - 1.544421 or 1.358099 - should one
take? They look too different and, for instance, lead to "unfair computing"
of empirical size (as rejection rate of null hypothesis) or empirical power
(as acception rate of alternative).




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