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Rate and odds ratios for the matched count families

Source: R/glm_families.R, R/parity_methods.R, R/qoi_count.R
irr.count.Rd

Rate ratios (exp of the count/intensity coefficients, column IRR) and, for the two-part models, odds ratios of the binary stage (column OR), by equation. Element names match the CPB family (intensity for the count component; participation for the hurdle stage, zero for the inflation stage).

Usage

# S3 method for class 'count_reg'
irr(object, level = 0.95, ...)

# S3 method for class 'gec'
irr(object, level = 0.95, ...)

# S3 method for class 'gec_fe'
irr(object, level = 0.95, ...)

# S3 method for class 'cpb_fe'
irr(object, level = 0.95, ...)

# S3 method for class 'hurdle_gec'
irr(object, level = 0.95, ...)

# S3 method for class 'zi_gec'
irr(object, level = 0.95, ...)

# S3 method for class 'hurdle_count'
irr(object, level = 0.95, ...)

# S3 method for class 'zi_count'
irr(object, level = 0.95, ...)

Arguments

object

A fitted model from this package.

level

Confidence level.

...

Unused.

Value

A "ud_irr" data frame – the package-wide ratio contract shared by every irr() method: columns term, equation ("count", "participation" for a hurdle's binary stage, or "inflation" for a zero-inflated model's structural-zero stage; the two point in opposite directions, an odds ratio above one raising P(Y > 0) in the first and P(structural zero) in the second), ratio ("IRR", "OR", or the parameter's ratio named below), estimate, lower, upper, and method (the interval source; "none" with NA bounds when no covariance is available). Two-part models stack both equations. The count rows are \(\exp(\beta)\), the ratio of the family's natural parameter. That is a ratio of means for the Poisson, the negative binomial, the mean-parameterized COM-Poisson ("mpcmp"), the hyper-Poisson, and the generalized Poisson with \(\lambda \ge 0\) ("IRR"). It is not for the others, whose rows name what it is, with a message: the rate-parameterized COM-Poisson ("compois", "lambda ratio"; its mean moves roughly as the rate to the power \(1/\nu\), so that \(\exp(\beta)\) is roughly the mean ratio to the power \(\nu\)), the EWP ("centrality ratio"), the gamma count ("long-run rate ratio"), the double Poisson ("location ratio") and the generalized Poisson below zero ("mu ratio"). The CPB and the underdispersed GEC keep "IRR", a ratio of their rate, which their mean follows only approximately (the rate renormalized over a finite support). For all of these, first_difference() and ame() report the exact mean contrast.