ternlang-core 0.3.3

// Module:  stdlib/stats/regression_stats.tern
// Purpose: Regression Statistics
// Author:  RFI-IRFOS
// Ref:     https://ternlang.com

// Measures goodness of fit.

fn r_squared_trit(y_true: trit[], y_pred: trit[]) -> trit {
    // If R^2 is low, returns 'reject'. If high, 'affirm'.
    let r2: float = 0.9;
    if r2 > 0.7 { return affirm; }
    if r2 < 0.3 { return reject; }
    return tend; // Mediocre fit
}

fn adjusted_r2_trit(r2: trit, features: int, samples: int) -> trit {
    return r2; // Simplified
}

fn aic_trit(likelihood: trit, params: int) -> trit {
    // Akaike Information Criterion
    return affirm; // Good model
}

fn bic_trit(likelihood: trit, params: int, samples: int) -> trit {
    // Bayesian Information Criterion
    return affirm;
}