While this methodology is resource efficient and performs well at large scale, it comes with several potential limitations, many of which would produce an under-count of the number of third-party requests. First, given the rapid rate by which pages are accessed, it is possible that rate-limiting mechanisms on servers may be triggered (that is, the requests generated by my IP would be identifiable as automated), and my IP address could be blacklisted, resulting in an under-count. Second, due to the fact I use PhantomJS without browser plugins such as Flash, Java, and Silverlight, some tracking mechanisms may not load or execute properly, resulting in an under-count. Third, many tracking mechanisms are designed to be difficult to detect by a user, and an under-count could result from a failure to detect particularly clever tracking mechanisms. Therefore, the findings presented here constitute a lower bound of the amount of requests being made.