In conducting this survey, ViewDNS.info took the top 100 sites in each category as listed in Alexa's 'Top Sites' directory and tested access to these sites from an Internet connection in the Islamic Republic of Iran (as per our Iran Firewall Test).
That is not 1 in 4 websites, it is not a representative sample at all.
100 websites from EACH of Alexa's 15 categories = 1500 sites. Sure the sample could have been bigger, but with millions, if not billions of websites in existance, what number would you class as a representative sample?
In conducting this survey, ViewDNS.info took the top 100 sites in each category as listed in Alexa's 'Top Sites' directory and tested access to these sites from an Internet connection in the Islamic Republic of Iran (as per our Iran Firewall Test).
That is not 1 in 4 websites, it is not a representative sample at all.