1. A computer-implemented method for sampling distributed streams of data, the method comprising computer-implemented operations for: receiving a data element at a coordinator device executing a sampling application, the data element comprising a binary string generated by a site server of a plurality of site servers in communication with the coordinator device, wherein the binary string comprises a first bit, a second bit, and a third bit, and wherein the binary string is transmitted by the site server in accordance with a probability established by the coordinator device; examining, by the coordinator device, the second bit of the binary string to determine whether to assign the data element to a lower sample or to assign the data element to a higher sample; determining, by the coordinator device, if the lower sample comprises a predetermined number of data elements; and taking an action, by the coordinator device, in response to determining that the lower sample comprises the predetermined number of data elements.