The ratings survey of Chinese mainland is mainly conducted by CCTV Sophomore Media Research Co., Ltd. (CSM). Briefly introduce its work flow and related knowledge: CCTV- Sophomore Media Research Co., Ltd. (CSM) is the largest and most authoritative ratings survey major in China.
The company has the largest TV audience survey network in China. By February 2000, the center had established nine provincial-level networks throughout the country.
There are 67 independent city survey stations with a total sample size of 1.85 million, and the ratings of nearly 700 major TV channels in China.
All-weather uninterrupted monitoring.
In order to better meet the demand of TV media and advertising industry for viewing survey services, CSM will continue according to market demand.
We will steadily expand the survey network and gradually introduce the latest international audience survey technology-personnel measuring instrument. Starting from 1999,
The company has opened the data service of personnel measuring instruments in Beijing, Guangzhou and Shanghai, and will establish the national personnel measuring instruments system one after another.
And the data network of personnel measuring instruments in 20 important cities.
investigation method
At present, CSM uses two methods to collect ratings data, namely diary method and personal measurement tool method.
Diary method refers to the method that all family members aged 4 and above in the sample family fill in diary cards to collect viewing information.
Law.
Each family member in the sample family has his own diary card, which requires them to record their daily TV watching (including
Record the channel and time period you watch on your diary card at any time. The time interval listed on the diary card is 15 minutes.
. Each diary card can record the viewing situation for a week. Interviewers regularly collect completed diary cards at home every week.
Keep a diary card for next week. In order to help interviewees identify the channels they are watching more intuitively, the interviewer will give
The sample family left an identification card including all channels.
Personnel measuring instrument method refers to the method of collecting TV viewing information by using "personnel measuring instrument", which is a common method in the world at present.
The latest survey of viewing styles.
Personnel measuring instrument consists of three parts: display instrument, storage box and hand controller. On the hand controller, each of the sample series
Each member has his own button, and there are also buttons for guests. When family members start watching TV, they should first press.
Click the button on the hand controller to represent yourself. Click this button again when you are not watching TV. Connect the TV and the handheld controller.
The connected monitor will remind you of the task of pressing the button and show the TV you are watching. The storage box can hold things to watch TV.
All information is stored in minutes (even accurate to the second) and then transmitted to the general manager through the telephone line.
The central computer of the department (or access data through PDA).
In the next few years, CSM plans to gradually replace diary method with personnel measurement method in some important fields.
Investigation process
The investigation process of CSM rating data can be roughly divided into the following four steps:
Basic research-extraction and maintenance of fixed samples-data acquisition-data processing
Step 1: Basic research
The audience rating survey is a sampling survey, so how to design it scientifically and reasonably according to the overall characteristics of the TV crowd?
The sampling scheme for obtaining representative samples becomes the decisive factor for checking the accuracy of data. And the foundation
The purpose of the study is to obtain the influencing factors of viewing behavior, such as the ownership of TV sets and related equipment, electricity
The coverage of video channels, the age, gender, family size and income of TV viewers are the survey samples.
The excerpts from this book provide a basis. At the same time, the results of basic research also provide decision-making basis for sample adjustment and rotation.
According to. CSM should not only conduct basic research when new stations are built, but also conduct basic research on existing stations once a year.
In order to grasp the changes of the overall structural characteristics of the survey and ensure the representativeness of the survey samples.
Step 2: Extraction and maintenance of fixed samples.
In the large sample of basic research, several families were randomly selected as fixed samples to participate in the rating.
Investigation. When CSM conducts fixed sampling on the spot, it insists on the important characteristics of sampled families (such as family size and number of TV sets).
, income level, the age of daily necessities buyers, the proportion of families with children and the proportion of wired families) and the conclusions of basic research
The results are as consistent as possible to ensure the representativeness of fixed samples.
The fixed sample size of CSM ratings survey takes into account the distribution characteristics of TV population in the survey area and the survey accuracy requirements.
In the case of investigating the cost, it is calculated by scientific methods.
Sample maintenance is very important for maintaining the representativeness of fixed samples, thus ensuring the accuracy and reliability of rating data.
Important significance. CSM attaches great importance to the maintenance of fixed samples and takes the following measures to maintain fixed samples.
：
A, sample rotation CSM rotates 2% of the sample families every week on average, so as to avoid the families being investigated from filling out diary cards for a long time.
Fatigue leads to unstable or declining filling quality;
B. Monitoring and adjustment of sample structure CSM monitors the control objectives of the sample every week to see the structural characteristics of the sample.
Whether the mark is consistent with the overall structural characteristics, and if the sample structure deviates from the overall structure, it will be repaired immediately.
Adjust the sample;
C. Large-scale basic research CSM conducts basic research once a year to provide the best sample rotation and adjustment.
New overall structural features.
Step 3: Data collection.
At present, CSM collects ratings data through two methods: diary method and personal measurement tool.
Step 4: Data processing
After the original data of viewing survey is input into the computer, the data should be purified first to ensure the original data.
Complete and reasonable. The purified data is merged with the sample background database and program database to form a more comprehensive ".
Rating database. On the basis of this "ratings database", the original data of ratings survey are analyzed.
Weighting calculation will produce various rating results and provide them to customers in the form of rating products.
sampling method
In ratings surveys, we usually adopt multi-stage sampling methods, such as two-stage sampling methods in cities.
First, select a certain number of homes (homes and villages) from the whole population.