The mobile phone has been at home, but it has received SMS big data.

It is normal to receive text messages and big data. When you buy this card, your information will be sold. So it is easy for people who monitor the epidemic to find you.

One is the source location method, that is, the location information is determined by the mobile data transmission mode of the mobile phone. This is different from the GPS we often hear. When the mobile phone sends and receives signals, it will automatically connect to the nearest signal transmission tower. Through the signaling data signal transmission tower containing base station information, all activities of mobile phones can be identified and traced, so as to track the location and path of mobile phone users. This is the most commonly used method and the most efficient big data screening method for this new epidemic. Second, through the analysis of social communication information, such as the contact between people in nearby communities and markets. This does not mean judging by social software information, but combining existing data, through telephone surveys, interviews and so on. After the outbreak of the epidemic in Beijing, nearly 65,438+10,000 community (village) workers in Beijing invested 7 120 communities (villages), and more than 300,000 people were investigated. Third, it can be confirmed by the information in the article. At the beginning of the epidemic in Beijing, after the analysis of the confirmed personnel, the Xinfadi market was determined as the birthplace, and then the seafood market was further determined. Found that the salmon chopping board carried the virus, and quickly investigated the close contacts related to the items. This is also an important means of investigation.