To ensure the diversity of samples, the recovery efficiency is often difficult to guarantee. Like the Yale graduates mentioned above, the cost of reaching is Special Database extremely high; and if we want to ensure high recovery efficiency, it is necessary to maintain a large sample library for a long time, which will inevitably lead to The sample quality is affected, such as patterns such as mutual answering communities. Another example can be explained from the side, the huge impact of high efficiency on quality. After the publication of "Jiangcun Economy Special Database " by Fei Xiaotong, the founder of Chinese sociology, Kaixiangong Village has become a holy place for field research. Under the influence of attracting a large number of Chinese and foreign sociologists, media, institutional teams, and student organizations to make pilgrimages over the Special Database years, the local people have long been skilled in coping. "Jiangcun" has never produced influential sociological works. For the data-oriented second half, it is bound to solve the shackles of reaching efficiency and cost. Questionnaire Star and Questionnaire Special Database Net take the traditional route. Both have developed apps, but the focus is on the creation and management of questionnaires. The respondents who reach the sample database still use SMS, email, etc., which are relatively inefficient. The Tencent questionnaire takes a social-based high stickiness route. The sample database of Tencent questionnaires simplifies the path of delivery and recycling, and forms Special Database a more efficient connection between givers and respondents by setting up the public account of “Uncle Juan and Filling the Circle” as a channel for receiving questionnaire tasks and rewards. After submitting the detailed personal information and registering successfully, whenever there is a questionnaire that meets the standard, the respondents Special Database of the sample database will receive the WeChat push of the service number of "Uncle Juan" as soon as possible.