e ensemble statistics.
% 
% In this context, we use "ensemble" to refer to any set of vector
% datasets using the same independent-variable coordinates.
% Ensemble data is common in climate science; model studies 
% often use intra-model ensembles to encompass uncertainty in initial
% conditions or parameters, and intermodel ensembles to further encompass
% structural uncertainties in model processes.  Timeseries data is also a
% prime candidate for this type of analysis, since we often want to look at
% in