Function learn_record 

pub fn learn_record(
    ballots: &[(String, String)],
    outcome: &str,
    records: &BTreeMap<String, Standing>,
    about: &[String],
) -> Result<(Vec<Trust>, BTreeMap<String, Standing>)>

Learn from an outcome by the record: each voter’s hits and misses so far, this outcome added, give its accuracy shrunk toward the panel’s (shrunk_accuracy), and the rows are the log odds of that scaled to the best voter at one (calibration_weights). Measured against Hedge’s multiplicative update on voters of known accuracy, the record reaches the batch calibration and Hedge does not: a voter is weighed by what it got right, not by how many times it has been punished. One outcome cannot tell voters apart, so the first leaves them equal. Rows are complete over the voters and scoped to about.

Errors

No outcome, or fewer than two voters.