Returns the value of the sum function
y = nisp_sum ( x , a )
a (nx+1)-by-1 or 1-by-(nx+1) matrix of doubles, where nx is the number of parameters
a np-by-nx matrix of doubles, where np is the number of experiments.
a np-by-1 matrix of doubles
This function returns the value of the Sum function.
This function is defined by
where X(i) are random variables with mean mu(i) and standard variation sigma(i), for i=1,2,...,nx.
"Sensitivity analysis in practice", Saltelli, Tarantolla, Compolongo, Ratto, Wiley, 2004
"An importance quantification technique in uncertainty analysis for computer models", Ishigami, Homma, 1990, Proceedings of the ISUMA'90. First international symposium on uncertainty modelling and Analysis, University of Maryland, USA, pp. 398-403.