# Public attention

Sampled hot-list observations, with source-specific ranks and heat.

## Unit and identity
Each row is one list appearance. id identifies that retained row; item_key groups source plus normalized topic wording across observations. Rank prefixes are removed before that key is computed. Translation changes do not define a new topic when the original title is retained.

## Coverage limits
The retained hot lists include Baidu, Weibo and Tencent WeChat. Collection gaps and changing source coverage affect comparisons. Source URLs may point to platform search results. Heat is publisher-specific and WeChat heat is unavailable.

## Fields
| Field | Meaning |
| --- | --- |
| id | Record ID |
| title | Title |
| title_lang | Title language |
| is_translated | Machine translation flag |
| source | Publisher |
| source_url | Original source |
| original_title | Original title |
| observed_at | Observed at |
| rank | Observed rank |
| heat | Publisher heat score |
| platform | Platform |
| board | Board |
| collected_at | Collected at |
| original_topic | Original topic |
| translated_topic | Translated topic |
| item_key | Stable source and normalized topic key |