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Beta response family

Source: R/family.R
beta.Rd

beta() defines a one-response distribution for continuous proportions strictly inside (0, 1), with formulas for mean mu and scale sigma.

Usage

beta()

Value

A drm_family object.

Details

The implemented contract is logit(mu) = eta_mu, log(sigma) = eta_sigma, and internal precision phi = 1 / sigma^2. Larger sigma therefore means more variation around the mean, not more precision. Ordinary unlabelled random intercepts and independent numeric slopes such as (1 | id) and (0 + x | id) may enter the logit-mu predictor; sigma remains fixed-effect in this first slice.

This helper masks base::beta() when drmTMB is attached. Use base::beta() for the mathematical beta function.

Examples

beta()
#> $name
#> [1] "beta"
#> 
#> $family
#> [1] "beta"
#> 
#> $n_response
#> [1] 1
#> 
#> $dpars
#> [1] "mu"    "sigma"
#> 
#> $links
#>      mu   sigma 
#> "logit"   "log" 
#> 
#> attr(,"class")
#> [1] "drm_family"