Hi all, I need everyone's instant attention on my query that usually which methodology specifically sampling method is used in web based survey method? My problem is that if I conduct a survey by Facebook then probably the data will biased because only limited types of friends circle I would have on my Facebook page so this will affect the data, therefore how to start a web based survey without baisness?? If I supposed to conduct the same survey on WhatsApp then also how I will get the mobile number of my representative populations?