The charts above are from a Datapraxis / YouGov Poll -- done in November and December of 2020 in 11 European countries. Here is the methodology:
A public opinion poll in eleven EU countries carried out for ECFR by Datapraxis and YouGov in late November and early December 2020.
This was an online survey conducted in Denmark (n = 1,037), France (n = 2,013), Germany (n = 2,060), Hungary (n=1,001), Italy (n=2,017), Netherlands (n = 1,005), Poland (n = 1,002), Portugal (n=1,004), Spain (n=1,017), Sweden (n = 1,010), and the GB (n=2,031). The results are politically and nationally representative samples.
The general margin of error is ±3% for 1,000 sample, and ±2% for 2,000. YouGov used purposive active sampling for this poll.
The exact dates of polling were: Denmark (20-25 November), France (25-26 November), Germany (25-27 November), Hungary (24 November – 2 December), Italy (24 November – 3 December), Netherlands (24 November – 2 December), Poland (24 November – 7 December), Portugal (24 November – 7 December), Spain (20-25 November), Sweden (24-27 November), and the GB (24-25 November).
