A fact checker is the person who checks factual assertions in non-fictional text, usually intended for publication in a periodical, to determine their veracity and correctness. The job requires general knowledge and the ability to conduct quick and accurate research. The resources and time needed for fact-checking means that this work is not done at most newspapers, where reporters’ timely ability to correct and verify their own data and information is chief among their qualifications. Publications issued on weekly, monthly, or infrequent bases are more likely to employ fact-checkers. Fact-checking, known as “research” at many publications, is most critical for those publishing material written by authors who are not trained reporters such writers being more likely to make professional, ethical, or mere factual mistakes. Fact-checking methods vary; some publications have neither the staff nor the budget needed for verifying every claim in a given article. Others will attempt just that, going so far as communicating with the authors’ sources to review the content of quotations. According to the Columbia Journalism Review, German weekly Der Spiegel runs “most likely the world’s largest fact checking operation”, employing the equivalent of eighty full-time fact checkers as of 2010. Typically, fact-checking is an entry-level publishing job at major magazines; fact-checker jobs at The New Yorker are considered prestigious and can lead to higher-level positions, usually at other magazines. Among the benefits of printing only checked copy is that it averts serious, sometimes costly, problems, e.g. lawsuits and discreditation. Fact checkers are primarily useful in catching accidental mistakes; they are not guaranteed safeguards against those who wish to commit journalistic frauds, such as Stephen Glass (who began his journalism career as a fact-checker). The fact checkers at The New Republic and other weeklies never flagged the numerous fictions in Glass’s reportage. Michael Kelly, who edited some of Glass’s concocted stories, blamed himself, rather than the fact-checkers: “Any fact-checking system is built on trust. . . . If a reporter is willing to fake notes, it defeats the system. Anyway, the real vetting system is not fact-checking but the editor.”