nispace.nulls.nulls_moran

nispace.nulls.nulls_moran(data_1d, dist_mat, n_nulls=1000, seed=None, **kwargs)

Moran Spectral Randomization (MSR) surrogate maps (Wagner & Dray 2015).

Generates surrogates via BrainSpace’s MoranRandomization, using a spatial weight matrix W built from dist_mat (standard 1/d weights by default, or a variogram-fitted covariance kernel if fit_variogram=True, falling back to 1/d if the map’s own Moran’s I is below variogram_threshold). Notable **kwargs: procedure (default "singleton"), joint, n_components (default 15), fit_variogram, variogram_n_bins/variogram_kernel/variogram_nugget/variogram_threshold. [8] (original MSR method); [9] (BrainSpace implementation).

Intended to be called through generate_null_maps(), which handles NaN masking, hemisphere splitting, and parallelization across maps — not meant to be called directly.