How is Google PageRank different from Quantcast Measure?

The  difference between these two is Google’s PageRank is the calculation of a page importance based on number and quality of incoming links to a website while Quantcast Measure is computed based on traffic recorded to a website as calculated through the Quantcast tag which is put on a website.

Mathematically, PageRank is an exponential scale between 0 and 10 while Quantcast ranks websites in order, by traffic- from 1 to 100,000 (typically).