get_M0_and_M1_matrices

pyapprox.optimal_experimental_design.get_M0_and_M1_matrices(homog_outer_prods, design_prob_measure, noise_multiplier, regression_type)[source]

Compute the matrices \(M_0\) and \(M_1\) used to compute the asymptotic covariance matrix \(C(\mu) = M_1^{-1} M_0 M^{-1}\) of the linear model

\[y(x) = F(x)\theta+\eta(x)\epsilon.\]

For least squares

\[M_0 = \sum_{i=1}^M\eta(x_i)^2f(x_i)f(x_i)^Tr_i\]
\[M_1 = \sum_{i=1}^Mf(x_i)f(x_i)^Tr_i\]

and for quantile regression

\[M_0 = \sum_{i=1}^M\frac{1}{\eta(x_i)}f(x_i)f(x_i)^Tr_i\]
\[M_1 = \sum_{i=1}^Mf(x_i)f(x_i)^Tr_i\]
Parameters
homog_outer_prodsnp.ndarray(num_factors,num_factors,num_design_pts)

The outer products \(f(x_i)f(x_i)^T\) for each design point \(x_i\)

design_prob_measurenp.ndarray (num_design_pts)

The weights \(r_i\) for each design point

noise_multipliernp.ndarray (num_design_pts)

The design dependent noise function \(\eta(x)\)

regression_typestring

The method used to compute the coefficients of the linear model. Currently supported options are lstsq and quantile.

Returns
M0np.ndarray (num_factors,num_factors)

The matrix \(M_0\)

M1np.ndarray (num_factors,num_factors)

The matrix \(M_1\)