Function ridge_prediction_intervals 

pub fn ridge_prediction_intervals(
    y_json: &str,
    x_vars_json: &str,
    new_x_json: &str,
    alpha: f64,
    lambda: f64,
    standardize: bool,
) -> String

Computes approximate Ridge regression prediction intervals via WASM.

Fits a Ridge model and computes conservative prediction intervals using leverage from unpenalized X’X and MSE from the ridge fit.

Arguments

• y_json - JSON array of response variable values
• x_vars_json - JSON array of predictor arrays (training data)
• new_x_json - JSON array of predictor arrays (new observations)
• alpha - Significance level (e.g., 0.05 for 95% PI)
• lambda - Regularization strength
• standardize - Whether to standardize predictors