export interface RareTerms {
    compoundTokens: string[];
    conceptPhrase: string[] | null;
}
export interface RareScorable {
    title: string;
    url: string;
    snippet: string;
}
export declare function detectRareTerms(query: string): RareTerms;
export declare function isRareTermMiss(result: RareScorable, rare: RareTerms): boolean;
export declare function rareTermFactor(result: RareScorable, rare: RareTerms): number;
//# sourceMappingURL=rare-terms.d.ts.map