8. A method comprising: interfacing with one or more end users via a server that includes a processor device and a memory; managing information related to one or more of the end users; determining, using one or more processing devices, a personality type for one or more end users from a particular set of personality types; and matching, using one or more processing devices, end users based on at least one end-user designated preference and on relationship rules of the personality types in the particular set of personality types, whereby the rules are based on statistically validated compatibilities between the personality types in the particular set of personality types, wherein the personality type of a user is determined from the particular set of personality types, and the determination of personality type from the particular set of personality types is based, at least in part, on: answers from the end users to questions provided by a central website including questions prompting end users for responses to pictures of human smiles, each response to a picture of a human smile including an end user assessment of whether the pictured smile is one of genuine or artificial, wherein the responses to questions prompting end users for responses to pictures of human smiles are used to infer hormonal levels of the respective end user and the determination of personality type from the particular set of personality types is further based on the inferred hormonal levels of the respective end user; word choices from the end users as found in the answers; and a frequency of word usage from the end users in the answers.
10. The method of claim 8 , wherein the determination of personality type from the particular set of personality types is further based on inferred levels of testosterone, serotonin, or estrogen.