A number between 0 and 1 indicating the esr value.
Details
By default
$$\frac{1}{1 + 2 \sum_{k = 1}^\infty\rho_k(\theta)}$$
from Brooks et al. (2011) where the infinite sum is truncated at
lag \(k\) when \(\rho_{k+1}(\theta) < 0\).
References
Brooks, S., Gelman, A., Jones, G.L., and Meng, X.-L. (Editors). 2011.
Handbook for Markov Chain Monte Carlo. Taylor & Francis, Boca Raton.