不確実性下の意思決定¶

// 不確実性を考慮した意思決定支援システムの概念コード
class UncertaintyAwareDSS {
  private decisionContext: DecisionContext;
  private uncertaintyModel: UncertaintyModel;
  private preferenceModel: PreferenceModel;
  private alternativeGenerator: AlternativeGenerator;

  constructor(context: DecisionContext) {
    this.decisionContext = context;
    this.uncertaintyModel = new UncertaintyModel(context);
    this.preferenceModel = new PreferenceModel(context);
    this.alternativeGenerator = new AlternativeGenerator(context);
  }

  // 意思決定分析の実行
  analyzeDecision(): DecisionAnalysis {
    // 不確実性の特性化
    const uncertaintyProfile = this.uncertaintyModel.characterizeUncertainty();

    // 決定問題の種類に基づいたアプローチ選択
    if (uncertaintyProfile.type === 'quantifiable_risk') {
      return this.performExpectedUtilityAnalysis();
    } else if (uncertaintyProfile.type === 'deep_uncertainty') {
      return this.performRobustnessAnalysis();
    } else {
      return this.performAdaptiveAnalysis();
    }
  }

  // 期待効用分析（リスクが定量化可能な場合）
  private performExpectedUtilityAnalysis(): DecisionAnalysis {
    const alternatives = this.alternativeGenerator.generateAlternatives();
    const utilityFunction = this.preferenceModel.getUtilityFunction();
    const probabilities = this.uncertaintyModel.getProbabilityDistributions();

    // 各選択肢の期待効用を計算
    const analyzedAlternatives = alternatives.map(alt => {
      const expectedUtility = this.calculateExpectedUtility(
        alt, utilityFunction, probabilities
      );

      return {
        alternative: alt,
        expectedUtility,
        riskProfile: this.calculateRiskProfile(alt, probabilities),
        sensitivityAnalysis: this.performSensitivityAnalysis(alt, probabilities)
      };
    });

    // 結果をランク付け
    const rankedAlternatives = this.rankAlternatives(analyzedAlternatives, 'expectedUtility');

    return {
      type: 'expected_utility_analysis',
      rankedAlternatives,
      uncertaintyProfile,
      recommendations: this.generateRecommendations(rankedAlternatives)
    };
  }

  // 頑健性分析（深い不確実性の場合）
  private performRobustnessAnalysis(): DecisionAnalysis {
    const alternatives = this.alternativeGenerator.generateAlternatives();
    const scenarios = this.uncertaintyModel.generateScenarios();

    // 各選択肢の各シナリオでの結果を評価
    const performanceMatrix = this.evaluatePerformanceAcrossScenarios(alternatives, scenarios);

    // 様々な頑健性指標を計算
    const robustnessMetrics = {
      minMax: this.calculateMinMaxMetric(performanceMatrix),
      minRegret: this.calculateMinRegretMetric(performanceMatrix),
      satisficing: this.calculateSatisficingMetric(performanceMatrix)
    };

    // 結果のランク付け（複数の頑健性指標に基づく）
    const rankedAlternatives = this.rankAlternativesByRobustness(
      alternatives, robustnessMetrics
    );

    return {
      type: 'robustness_analysis',
      rankedAlternatives,
      performanceMatrix,
      robustnessMetrics,
      recommendations: this.generateRobustnessRecommendations(rankedAlternatives)
    };
  }

  // 適応的分析（変化する不確実性の場合）
  private performAdaptiveAnalysis(): DecisionAnalysis {
    const initialAlternatives = this.alternativeGenerator.generateInitialActions();
    const futureOptions = this.alternativeGenerator.generateFutureOptions();
    const signposts = this.uncertaintyModel.identifySignposts();

    // 適応的戦略のパスウェイを構築
    const adaptivePathways = this.buildAdaptivePathways(
      initialAlternatives, futureOptions, signposts
    );

    // 初期アクションの評価
    const evaluatedInitialActions = this.evaluateInitialActions(
      initialAlternatives, adaptivePathways
    );

    return {
      type: 'adaptive_analysis',
      evaluatedInitialActions,
      adaptivePathways,
      signposts,
      recommendations: this.generateAdaptiveRecommendations(evaluatedInitialActions)
    };
  }

  // 補助メソッド
  private calculateExpectedUtility(
    alternative: Alternative, 
    utilityFunction: UtilityFunction, 
    probabilities: ProbabilityDistribution[]
  ): number { /* 実装 */ }

  private calculateRiskProfile(
    alternative: Alternative, 
    probabilities: ProbabilityDistribution[]
  ): RiskProfile { /* 実装 */ }

  private performSensitivityAnalysis(
    alternative: Alternative, 
    probabilities: ProbabilityDistribution[]
  ): SensitivityAnalysis { /* 実装 */ }

  private evaluatePerformanceAcrossScenarios(
    alternatives: Alternative[], 
    scenarios: Scenario[]
  ): PerformanceMatrix { /* 実装 */ }

  // その他のヘルパーメソッド...
}