import { InformationRatioOptions } from '../schemas/InformationRatioOptionsSchema';
import { InformationRatioResult } from '../schemas/InformationRatioResultSchema';
/**
 * Calculate Information Ratio
 *
 * Information Ratio measures the efficiency of a portfolio manager's ability to generate
 * excess returns relative to a benchmark. It's the ratio of mean excess return to tracking error.
 *
 * Formula:
 * - Excess Returns: r_excess = r_portfolio - r_benchmark
 * - Mean Excess Return: μ_excess = Σ(r_excess) / n
 * - Tracking Error: TE = √(Σ(r_excess - μ_excess)² / (n-1)) * √(annualization_factor)
 * - Information Ratio: IR = μ_excess / TE
 *
 * Where:
 * - n = number of periods
 * - μ_excess = mean of excess returns
 *
 * @param options - Portfolio returns, benchmark returns, and calculation parameters
 * @returns Information ratio result with period and annualized values
 *
 * @example
 * ```typescript
 * const informationRatio = calculateInformationRatio({
 *   portfolioReturns: [0.05, 0.03, 0.07, 0.02],
 *   benchmarkReturns: [0.04, 0.03, 0.06, 0.02],
 *   annualizationFactor: 252
 * });
 * ```
 */
export declare function calculateInformationRatio(options: InformationRatioOptions): InformationRatioResult;