RE: Quantcast people vs uniques3 Feb 2016 14:19
It doesn't make people a precise metric, does it if it's only estimated? Lots of people will have just one device they use in a day, I've got up to seven and probably use five every day. I appreciate that's a bit of an outlier, but so is just one device, it has to be somewhere in between which leaves a massive margin of error.
That's why I prefer page views, because that is what the site actually experiences and every page view is an earning opportunity.
Apart from choosing which metric is preferable as reliable, there's the issue of bots and pay per clicks being counted as people. Having looked in the past at third party websites estimating my traffic I'm inclined to treat them as not much more than an informed stab in the dark and nothing to get too excited about.