Classes of correlation structures available in the brms package.
cor_brms is not a correlation structure itself,
but the class common to all correlation structures implemented in brms.
autoregressive-moving average (ARMA) structure, with arbitrary orders for the autoregressive and moving average components
autoregressive (AR) structure of arbitrary order
moving average (MA) structure of arbitrary order
response autoregressive (ARR) structure
Spatial conditional autoregressive (CAR) structure
Spatial simultaneous autoregressive (SAR) structure
Bayesian structural time series (BSTS) structure
fixed user-defined covariance structure