Possibly from 18th and 19th century slang term to pull yorkshire on a person meaning "to trick or deceive" them
Yorker Sentence Examples
On the 2nd of March 1834, Greeley and Winchester issued the first number of The New Yorker, a weekly literary and news paper, the firm then supposing itself to be worth about $3000.
By the end of the third year The New Yorker had reached a circulation of 9500 copies, and had sustained a total loss of $7000.
During the publication of The New Yorker he added to the scanty income which the job printing brought him by supplying editorials to the short-lived Daily Whig and various other publications.
He continued The New Yorker, and travelled between Albany and New York each week to edit the two papers.
In September 1841 Greeley merged his weekly papers, The Log Cabin and The New Yorker, into The Weekly Tribune, which soon attained as wide circulation as its predecessors, and was much more profitable.