Delta method for consumption uncertainty propagation
Source:R/15.4-analysis-uncertainty.R
predict_consumption_delta.RdPropagates p-value uncertainty to consumption predictions using the delta method. Computes numerical derivatives and applies first-order approximation for uncertainty propagation. Suitable when the relationship between p and consumption is approximately linear.
Usage
predict_consumption_delta(
p_est,
p_se,
bio_obj,
delta_size = 0.001,
first_day = 1,
last_day = 365,
verbose = FALSE
)Arguments
- p_est
Estimated p-value (feeding level parameter)
- p_se
Standard error of p-value estimate
- bio_obj
Bioenergetic object with simulation settings and environmental data
- delta_size
Small increment for numerical derivative computation, default 0.001
- first_day
First simulation day, default 1
- last_day
Last simulation day, default 365
- verbose
Show progress messages, default FALSE
Details
The delta method uses first-order Taylor series approximation: Var(f(X)) ≈ [f'(μ)]² × Var(X)
The linearity check verifies that the derivative times delta_size is small relative to the consumption estimate, indicating local linearity.
Examples
if (FALSE) { # \dontrun{
# Propagate uncertainty from MLE estimate
mle_result <- run_fb4(bio_obj, strategy = "mle", observed_weights = weights)
p_est <- mle_result$summary$p_estimate
p_se <- mle_result$method_data$confidence_intervals$p_se
uncertainty_result <- predict_consumption_delta(
p_est = p_est,
p_se = p_se,
bio_obj = bio_obj
)
} # }