该对象以指标（metrics）数组的形式与展示关联。这些指标可提供关于展示的洞察以辅助决策（decisioning），如近期平均可见性（viewability）、点击率等。每条指标由其类型标识、上报指标取值，并可选地标明测量该取值的来源或供应商。译稿校对中ENThis object is associated with an impression as an array of metrics. These metrics can offer insight into the impression to assist with decisioning such as average recent viewability, click-through rate, etc. Each metric is identified by its type, reports the value of the metric, and optionally identifies the source or vendor measuring the value.
| Attribute | Type | Description |
|---|---|---|
| type required | string | 所呈现指标的类型，使用交易平台（exchange）预先整理（curated）的字符串名称，该名称应事先（a priori）向竞价方公布。译稿校对中ENType of metric being presented using exchange curated string names which should be published to bidders a priori. |
| value required | float | 表示指标取值的数值。概率类指标必须落在 0.0 – 1.0 区间内。译稿校对中ENNumber representing the value of the metric. Probabilities must be in the range 0.0 – 1.0. |
| vendor | string | 取值的来源，使用交易平台预先整理（curated）的字符串名称，该名称应事先（a priori）向竞价方公布。若来源为交易平台自身而非第三方，建议使用 “EXCHANGE”。译稿校对中ENSource of the value using exchange curated string names which should be published to bidders a priori. If the exchange itself is the source versus a third party, “EXCHANGE” is recommended. |
| ext | object | 供交易平台对 OpenRTB 进行专属扩展（exchange-specific extensions）的占位对象。译稿校对中ENPlaceholder for exchange-specific extensions to OpenRTB. |
译注
译者注Metric：以数组形式与 Imp 关联，为展示提供洞察以辅助决策（decisioning），如近期平均可见性（viewability）、点击率等；业内文档一般保留英文对象名 Metric。译稿校对中
供给侧质量信号的实践用法：可见性预估、历史 CTR 等指标可作为出价策略的输入，但均为供给侧单方声明，买方应结合自身数据校验后再用于调价，避免单凭预估指标激进出价。译稿校对中
type / vendor 的受控词表：二者均为交易平台整理的字符串名称，须事先向竞价方公布，否则无法解析语义；解析时应对未知取值做容错（忽略而非拒绝整条请求）。译稿校对中
字段描述收录自 IAB Tech Lab OpenRTB 2.6 官方规范（CC-BY 3.0）· 枚举值来源 AdCOM 1.0 · 初稿校对中