www.gusucode.com > wavelet 源码程序 matlab案例代码 > wavelet/BiasedvsUnbiasedEstimatorsWaveletVarianceExample.m

    %% Compare Number of Coefficients for Unbiased and Biased Variance Estimates
% Compare the number of coefficients for unbiased and biased wavelet 
% variance estimates. For the unbiased (default) estimates, the number of 
% nonboundary coefficients decreases by scale. For biased estimates, the 
% number of coefficients matches the number of input rows and is constant 
% for every scale.
%%
% Obtain the MODWT of the Southern Oscillation Index data using the
% Fejer-Korovkin wavelet with eight coefficients. Compute the unbiased and
% biased estimates of the wavelet variance down to level ten. The number of
% coefficients used in the unbiased estimates decrease by scale.

% Copyright 2015 The MathWorks, Inc.

load soi
wsoi = modwt(soi,'fk8');
[wvar_unb,wvarci_unb,nj_unb] = modwtvar(wsoi,'fk8');
[wvar_b,wvarci_b,nj_b] = modwtvar(wsoi,'fk8',[],'EstimatorType','biased');
[nj_unb(1:10),nj_b(1:10)]