SELECT T1.name FROM useracct AS T1 JOIN trust AS T2 ON T1.u_id = T2.source_u_id GROUP BY T2.source_u_id ORDER BY AVG(trust) DESC LIMIT 1
Find the name of the source user with the highest average trust score.
CREATE TABLE review (
    a_id number,
    u_id number,
    i_id number,
    rating number,
    rank number
)

CREATE TABLE useracct (
    u_id number,
    name text
)

CREATE TABLE item (
    i_id number,
    title text
)

CREATE TABLE trust (
    source_u_id number,
    target_u_id number,
    trust number
)