1. A method comprising: receiving, at a coordinator device executing a sampling application, a data element comprising a binary string, the 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 first sample or to assign the data element to a second sample; determining, by the coordinator device, if the first sample comprises a predetermined number of data elements; and taking an action, by the coordinator device, in response to determining that the first sample comprises the predetermined number of data elements.