
Continuation Ratio Regression Inference for Ordinal Responses
Source:R/inference_ordinal_stereotype_logit.R
InferenceOrdinalContRatioRegr.RdFits a conditional (stratified) continuation-ratio logit model for ordinal
responses: for cut \(j = 1, \dots, K-1\), among subjects who have
reached at least category \(j\), $$\log\frac{\Pr(Y_i > j \mid Y_i
\ge j)}{\Pr(Y_i = j \mid Y_i \ge j)} = \alpha_j + \beta_T W_i + X_i^\top
\gamma,$$ a discrete-time-hazard-model analog for ordinal data, with a
treatment coefficient \(\beta_T\) constrained equal across all cuts.
\(\exp(\hat\beta_T)\) is the common "continue vs. stop here" odds ratio:
a positive \(\beta_T\) means treatment pushes subjects toward higher
categories of \(Y\), matching the sign convention of every other ordinal
estimator in the package.
Fitting proceeds by expand_continuation_ratio_data_cpp's
stacked-binary expansion followed by conditional logistic regression on
the expanded data. likelihood_tier = "full": likelihood-ratio,
score, gradient, and Wald tests are all available when the model
converges, plus parametric-likelihood-bootstrap calibration of the
likelihood-ratio test. Validity requires the continuation-ratio
proportionality assumption (a common \(\beta_T\) across all \(K-1\)
cuts).
Computes the randomization distribution of the treatment effect estimate under the sharp null.
Whether compute_rand_two_sided_pval() is actually
usable on this instance right now – FALSE exactly when it
would stop(): an incidence-response instance with no
custom randomization statistic and a design not eligible for
design-randomization-based incidence inference (see
private$should_use_design_randomization_for_incidence()).
TRUE for every other case, including every non-incidence
response type. Public, self-contained (only reads already-set
instance state, no side effects), so InferenceSuite can
check this before attempting the sentinel instead of relying on
the stop() being silently swallowed into a pval = NA
"ok" row – the single source of truth for both this check and
compute_rand_two_sided_pval()'s own guard, so the two can
never drift apart.
Computes a randomization-based p-value.
Value
When debug = FALSE (default), a numeric vector of length r. When
debug = TRUE, a list with: values, errors (list of character
vectors, one per iteration), warnings (list of character vectors, one per
iteration), num_errors, num_warnings,
prop_iterations_with_errors, prop_iterations_with_warnings, and
prop_illegal_values.
A single logical.
Randomization p-value.
References
Agresti, A. (2010). Analysis of Ordinal Categorical Data (2nd ed.). Wiley, for the continuation-ratio model family.
See also
InferenceOrdinalStereotypeLogitRegr
and
InferenceOrdinalKKCondAdjCatLogitRegr
for related ordinal-logit expansions. See also:
Ordinal
regression (Wikipedia).
Super class
Inference -> InferenceOrdinalContRatioRegr
Methods
+ inherited public methods from Inference
Inference$capabilities()Inference$compute_asymp_confidence_interval()Inference$compute_asymp_two_sided_pval()Inference$compute_estimate()Inference$compute_exact_confidence_interval()Inference$compute_exact_two_sided_pval_for_treatment_effect()Inference$duplicate()Inference$get_analysis_data()Inference$get_covariates()Inference$get_design_object()Inference$get_model_formula()Inference$get_nonestimable_reason()Inference$get_nonestimable_stage()Inference$get_optimization_alg()Inference$get_response()Inference$get_response_type()Inference$get_treatment()Inference$initialize()Inference$is_nonestimable()Inference$set_optimization_alg()Inference$set_seed()Inference$supports()
InferenceOrdinalContRatioRegr$approximate_randomization_distribution_beta_hat_T()
Usage
InferenceOrdinalContRatioRegr$approximate_randomization_distribution_beta_hat_T(
r = 501,
delta = 0,
transform_responses = "none",
show_progress = TRUE,
permutations = NULL,
debug = FALSE,
zero_one_logit_clamp = .Machine$double.eps
)Arguments
rNumber of randomization vectors. Default 501.
rNumber of randomization vectors.
deltaThe null difference. Default 0.
deltaNull difference.
transform_responsesType of transformation. Default "none".
transform_responsesTransformation.
show_progressShow progress bar. Default TRUE.
show_progressShow progress.
permutationsPre-computed permutations. Default NULL.
permutationsPre-computed permutations.
debugIf
TRUE, return a list with the distribution values and per-iteration diagnostics including error messages, warning messages, counts of each, and summary proportions for iterations with errors, warnings, and illegal (non-finite) values. Runs serially. DefaultFALSE.zero_one_logit_clampThe clamping amount for exact 0 and 1 values when logging
zero_one_logit_clampThe clamping amount for exact 0 and 1 values when logging
InferenceOrdinalContRatioRegr$compute_rand_two_sided_pval()
Usage
InferenceOrdinalContRatioRegr$compute_rand_two_sided_pval(
r = 501,
delta = 0,
transform_responses = "none",
na.rm = TRUE,
show_progress = TRUE,
permutations = NULL,
zero_one_logit_clamp = .Machine$double.eps
)Arguments
rNumber of randomization vectors. Default 501.
rNumber of randomization vectors.
deltaThe null difference. Default 0.
deltaNull difference.
transform_responsesType of transformation. Default "none".
transform_responsesTransformation.
na.rmRemove NAs.
show_progressShow progress bar. Default TRUE.
show_progressShow progress.
permutationsPre-computed permutations. Default NULL.
permutationsPre-computed permutations.
zero_one_logit_clampThe clamping amount for exact 0 and 1 values when logging
zero_one_logit_clampThe clamping amount for exact 0 and 1 values when logging
Examples
# \donttest{
seq_des = DesignSeqOneByOneBernoulli$new(n = 10, response_type = 'ordinal')
for (i in 1:10) {
seq_des$add_one_subject_to_experiment_and_assign(data.frame(x1 = rnorm(1)))
}
seq_des$add_all_subject_responses(sample(1:4, 10, replace = TRUE))
inf = InferenceOrdinalContRatioRegr$new(seq_des)
inf$compute_estimate()
#> [1] -6.94967
# }