Struct IdealPointUser 

pub struct IdealPointUser {
    pub center: Vec<f64>,
    pub weights: Vec<f64>,
}

A simulated user with an ideal point: there is a sound they are looking for, and both too little and too much of any quality is worse.

u*(φ) = −Σ w_i (φ_i − c_i)²

This exists because every other user in this module is linear in the same φ the model is linear in, which makes the model well specified by construction. Under that setup “can it learn taste” collapses to “how fast does a correctly-specified linear model estimate its coefficients”, and no amount of passing it says anything about a real listener. A gate that cannot fail is not a gate.

The misspecification here is not a matter of degree, it is structural. u = max_k θ_k · φ is a maximum of affine functions, and a maximum of affine functions is convex, always. The utility above is strictly concave (negative-definite quadratic). So no K, however large, brings the model closer to this user in the way extra experts help elsewhere — adding lenses can only build a better convex function. The model can still track the local gradient and rank most pairs, and that is the useful thing to measure; what it cannot do is be right everywhere at once, and a harness that never notices the difference is not measuring anything.

Fields

center: Vec<f64>

The sound being looked for, in standardized feature space.

weights: Vec<f64>

How sharply each coordinate is judged.

Implementations

impl IdealPointUser

pub fn utility(&self, phi: &[f64]) -> f64

True utility: how close this candidate is to the ideal, penalized per coordinate.

pub fn duel<R: Rng>(&self, rng: &mut R, a: &[f64], b: &[f64]) -> bool

Sample a duel outcome (true = chose A), Bradley–Terry noise.

pub fn observe_duel<R: Rng>( &self, rng: &mut R, a: Vec<f64>, b: Vec<f64>, session: usize, ) -> Observation

Generate a full duel observation on the given pair.

Trait Implementations

impl Clone for IdealPointUser

fn clone(&self) -> IdealPointUser

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for IdealPointUser

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.