Вот только опросы проводятся по доступной базе ... стационарных телефонов.
Об этом, и подобных нарушениях репрезентативности, в той статье упоминалось. Я перечислю моменты
1) Ipsos опрос перед выборами, который, в отличие от стандартной Ipsos методологии, проводился онлайн. Проводился среди резидентов, а не среди тех, кто скорее всего проголосует (у нас при т/ф опросах спрашивают: вы точно проголосуете, вероятно проголосуете, вероятно не проголосуете, не проголосуете)
Цитата:
Internet-based polls are very likely to be a part of polling’s future, and my view is not necessarily that they should be dismissed out of hand. However, they need to be approached with caution.
The central challenge that Internet polls face is in collecting a random sample, which is the sine qua non of a scientific survey. There is no centralized database of e-mail addresses, nor any other method to “ping” someone at random to invite them to participate in an online poll. Many people have several e-mail addresses, while about 20 percent of Americans still do not go online at all.
2) Стационарные т/ф опросы тоже проблематичны по аналогичным причинам:
Цитата:
Some telephone polls, especially those that are conducted through automated scripts, do not call cellphone numbers, even though more than a quarter of American households do not have landline telephones at all, with the fraction increasing by several percentage points every year. Meanwhile, households often share a single number between a family, or they have multiple telephone lines; careful pollsters take steps to ensure that their samples are not biased by these problems, but others apply a blitzkrieg approach to polling and do not.
3) Суперсерьезное отношение:
Цитата:
At the favorable extreme is the company Knowledge Networks, which goes so far as to provide Internet service to people who do not already have it.
Тоже неплохо:
Цитата:
The company YouGov, meanwhile, which has produced reasonably accurate results with online polls, recruits participants by advertising at nonpolitical websites, and relies on databases of e-mail addresses that they purchase from marketers. While not strictly random, this method has some promise of developing a relatively unbiased sample, as it is not correlated with political ideology in any obvious way.
4) А вот эта компания просто халтурщики (я бы сказал, продают гнилой товар)
Цитата:
At the other end of the spectrum are online polls that are blatantly unscientific. The worst example is the company IBOPE Zogby, which has had extremely inaccurate results in past elections. Rather than making any effort to recruit a random sample, the company instead relies on people who sign up for the survey voluntarily. What’s worse, Zogby encourages people who are in their database to invite their friends to join the panel as well.