1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194
|
# generic function for CI calculation
.ci_generic <- function(model,
ci = 0.95,
method = "wald",
dof = NULL,
effects = "fixed",
component = "all",
vcov = NULL,
vcov_args = NULL,
verbose = TRUE,
...) {
# check method
if (is.null(method)) {
method <- "wald"
}
method <- tolower(method)
method <- insight::validate_argument(
method,
c(
"wald", "ml1", "betwithin", "kr", "satterthwaite", "kenward", "boot",
"profile", "residual", "normal"
)
)
effects <- insight::validate_argument(effects, c("fixed", "random", "all"))
component <- insight::validate_argument(
component,
c(
"all", "conditional", "zi", "zero_inflated", "dispersion", "precision",
"scale", "smooth_terms", "full", "marginal"
)
)
if (method == "ml1") { # nolint
return(ci_ml1(model, ci = ci))
} else if (method == "betwithin") {
return(ci_betwithin(model, ci = ci))
} else if (method == "satterthwaite") {
return(ci_satterthwaite(model, ci = ci))
} else if (method %in% c("kenward", "kr")) {
return(ci_kenward(model, ci = ci))
}
# default CIs follow here (methods wald, boot, profile, residual, normal)
out <- lapply(ci, function(i) {
.ci_dof(
model = model,
ci = i,
dof = dof,
effects = effects,
component = component,
method = method,
vcov = vcov,
vcov_args = vcov_args,
verbose = verbose,
...
)
})
out <- do.call(rbind, out)
row.names(out) <- NULL
out
}
#' @keywords internal
.ci_dof <- function(model,
ci,
dof,
effects,
component,
method = "wald",
se = NULL,
vcov = NULL,
vcov_args = NULL,
verbose = TRUE,
...) {
# need parameters to calculate the CIs
if (inherits(model, "emmGrid")) {
params <- insight::get_parameters(
model,
effects = effects,
component = component,
merge_parameters = TRUE
)
} else {
params <- insight::get_parameters(model,
effects = effects,
component = component,
verbose = FALSE
)
}
# check if all estimates are non-NA
params <- .check_rank_deficiency(model, params, verbose = FALSE)
# for polr, we need to fix parameter names
params$Parameter <- gsub("Intercept: ", "", params$Parameter, fixed = TRUE)
# validation check...
if (is.null(method)) {
method <- "wald"
}
method <- tolower(method)
# Fist, we want standard errors for parameters
# --------------------------------------------
# if we have adjusted SE, e.g. from kenward-roger, don't recompute
# standard errors to save time...
if (is.null(se)) {
if (!is.null(vcov) || isTRUE(list(...)[["robust"]])) {
# robust (HC) standard errors?
stderror <- standard_error(model,
component = component,
vcov = vcov,
vcov_args = vcov_args,
verbose = verbose,
...
)
} else {
# normal standard errors, including small-sample approximations
stderror <- switch(method,
kenward = se_kenward(model),
kr = se_kenward(model),
satterthwaite = se_satterthwaite(model),
standard_error(model, component = component)
)
}
# if we have a non-empty stderror, use it
if (insight::is_empty_object(stderror)) {
return(NULL)
}
# filter non-matching parameters, resp. sort stderror and parameters,
# so both have the identical order of values
if (nrow(stderror) != nrow(params) ||
!all(stderror$Parameter %in% params$Parameter) ||
!all(order(stderror$Parameter) == order(params$Parameter))) {
params <- stderror <- merge(stderror, params, sort = FALSE)
}
se <- stderror$SE
}
# Next, we need degrees of freedom
# --------------------------------
# check if we have a valid dof vector
if (is.null(dof)) {
# residual df
dof <- insight::get_df(x = model, type = method, verbose = FALSE)
# make sure we have a value for degrees of freedom
if (is.null(dof) || length(dof) == 0 || .is_chi2_model(model, dof)) {
dof <- Inf
} else if (length(dof) > nrow(params)) {
# filter non-matching parameters
dof <- dof[seq_len(nrow(params))]
}
}
# Now we can calculate CIs
# ------------------------
alpha <- (1 + ci) / 2
fac <- suppressWarnings(stats::qt(alpha, df = dof))
out <- cbind(
CI_low = params$Estimate - se * fac,
CI_high = params$Estimate + se * fac
)
out <- as.data.frame(out)
out$CI <- ci
out$Parameter <- params$Parameter
out <- out[c("Parameter", "CI", "CI_low", "CI_high")]
if ("Component" %in% names(params)) out$Component <- params$Component
if ("Effects" %in% names(params) && effects != "fixed") out$Effects <- params$Effects
if ("Response" %in% names(params)) out$Response <- params$Response
# for cox-panel models, we have non-linear parameters with NA coefficient,
# but test statistic and p-value - don't check for NA estimates in this case
if (anyNA(params$Estimate) && !inherits(model, "coxph.penal")) {
out[stats::complete.cases(out), ]
} else {
out
}
}
.is_chi2_model <- function(model, dof) {
statistic <- insight::find_statistic(model)
(all(dof == 1) && identical(statistic, "chi-squared statistic"))
}
|