1. A computer-implemented method for analyzing a first web site or mobile device app interaction, the method comprising acts of: identifying an anchor value X from the first web site or mobile device app interaction, wherein the anchor value X is of an anchor type selected from a group consisting of: account identifier, email address, phone number, credit card number, device identifier, device characteristic, network address, and location; identifying a first plurality of past digital interactions from which the anchor value X was observed, wherein each past digital interaction of the first plurality of past digital interactions has associated therewith a respective sameness score; filtering the first plurality of past digital interactions based at least in part on the respective sameness scores, to thereby obtain a second plurality of past digital interactions, wherein the second plurality of past digital interactions comprise fewer digital interactions than the first plurality of past digital interactions; generating a dynamic profile for the anchor value X based on the second plurality of past digital interactions, wherein: the dynamic profile comprises historical information regarding each attribute of a plurality of attributes; and the plurality of attributes are selected based on measurements taken from the second plurality of past digital interactions; for at least one attribute A 1 of the plurality of attributes, determining a value V 1 based on one or more measurements taken from the first web site or mobile device app interaction, wherein the one or more measurements relate to a physical interaction between a user and a device; determining a biometric score for the first web site or mobile device app interaction at least in part by comparing the value V 1 of the at least one attribute A 1 against the historical information regarding the at least one attribute A 1 ; and displaying, via a backend user interface, a risk assessment report to an operator of a web site or mobile device app via which the first web site or mobile device app interaction is conducted, wherein the risk assessment report is based on the biometric score for the first web site or mobile device app interaction.