1 前言 现行收视率调查通常是通过请观众填写问卷的方式来获取资料。显然,这种方式有许多敝端,资料误差很大。近来,出现了一些结合有线电视频道变换器的用户收视资料收集仪。基本原理见图1。每当用户选择收看电视节目时,其收看的频道、时间等信息被记录在IC卡上。定期取回IC卡,将数据录 1 Introduction The prevailing ratings survey is usually obtained by asking the audience to fill in the questionnaire. Obviously, there are many ways to deal with this method, and the data error is very large. Recently, there have been some user ratings data collectors incorporating cable channel changers. The basic principle is shown in Figure 1. Whenever the user chooses to watch the television program, the channel, time and other information watched on the IC card is recorded. Regularly retrieve the IC card, the data recorded