/**
 * balance.ts — find the database entries that are out of line with their peers.
 *
 * Balance is relative: a skill dealing 400 damage is fine in a game where
 * everything does, and broken in one where nothing else breaks 60. So rather
 * than checking numbers against thresholds invented here, each entry is scored
 * on a power metric and compared against the OTHER entries in its category.
 *
 * The comparison is leave-one-out: the mean and standard deviation an entry is
 * judged against exclude that entry. Without it a single extreme value inflates
 * the very statistics meant to catch it — the more broken the outlier, the
 * further it drags the mean toward itself, and past a point it hides
 * completely. Same reason one bad measurement should never help decide whether
 * it is bad.
 *
 * A formula the evaluator cannot read statically is reported separately, never
 * scored as zero. Counting unreadable formulas as no damage would pull every
 * average down and quietly break the whole analysis.
 */
export interface BalanceOutlier {
    id: number;
    name: string;
    value: number;
    /** How many standard deviations from the leave-one-out mean. */
    deviations: number;
    direction: 'high' | 'low';
    message: string;
}
export interface BalanceCategory {
    category: string;
    /** What was measured, in words, so the numbers can be argued with. */
    metric: string;
    sampled: number;
    /** Entries with no meaningful value for this metric (free skills, etc.). */
    skipped: number;
    stats: {
        mean: number;
        sd: number;
        min: number;
        max: number;
        median: number;
    } | null;
    outliers: BalanceOutlier[];
    /** The extremes, for context, whether or not they were flagged. */
    highest: {
        id: number;
        name: string;
        value: number;
    }[];
    lowest: {
        id: number;
        name: string;
        value: number;
    }[];
}
export interface UnreadableFormula {
    id: number;
    name: string;
    formula: string;
    reason: string;
}
export interface BalanceReport {
    thresholdSd: number;
    outlierCount: number;
    categories: BalanceCategory[];
    /**
     * Damage formulas that could not be evaluated without executing them. These
     * are excluded from the statistics rather than counted as zero.
     */
    unreadableFormulas: UnreadableFormula[];
}
/**
 * Analyse a project's database for balance outliers.
 *
 * Read-only. `thresholdSd` is how far from its peers an entry has to sit before
 * it is worth mentioning; 2 standard deviations is the usual convention and
 * flags roughly the most extreme 5% of a normal distribution.
 */
export declare function analyseBalance(projectPath: string, opts?: {
    thresholdSd?: number;
    category?: string;
}): Promise<BalanceReport>;