{
  "disclosure": "The article preserves the advertising-platform revenue-analysis scenario and methods. Customer, app and internal metric names use generic aliases. Platform ad revenue is distinct from advertiser-side return. All amounts and concrete example events are independently fictional, not renamed or scaled production data. The validator is an independent teaching implementation, not a production run.",
  "metric": "广告收入（通用代称）",
  "unit": "万元",
  "period": "同口径、同长度的两个完整演示周期",
  "before_total": 800,
  "after_total": 740,
  "groups": [
    {"name": "客户甲", "before": 300, "after": 210},
    {"name": "客户乙", "before": 200, "after": 250},
    {"name": "其他", "before": 300, "after": 280}
  ],
  "hierarchy_example": {
    "parent": "客户甲",
    "children": [
      {"name": "应用 A", "before": 180, "after": 100},
      {"name": "其余应用", "before": 120, "after": 110}
    ]
  },
  "ratio_example": {
    "metric": "投放回报（通用代称）",
    "definition": "广告带来的用户在约定观察期内产生的回报金额，除以对应广告花费；衡量客户的广告投放效果，不是平台广告收入。",
    "unit": "金额均为万元；比值以百分比表示",
    "numerators": [4, 12],
    "denominators": [10, 60]
  }
}