Effron pseudo r-squared.
References
Efron, B. (1978). Regression and ANOVA with zero-one data: Measures of residual variation. Journal of the American Statistical Association, 73, 113-121.
See also
Other model fit statistics:
blr_model_fit_stats()
,
blr_multi_model_fit_stats()
,
blr_pairs()
,
blr_rsq_adj_count()
,
blr_rsq_cox_snell()
,
blr_rsq_mcfadden_adj()
,
blr_rsq_mckelvey_zavoina()
,
blr_rsq_nagelkerke()
,
blr_test_lr()