STAMFORD, Conn.--(BUSINESS WIRE)--Gartner, Inc. (NYSE: IT), the leading provider of research and analysis on the global information technology industry, will hold its annual Investor Day for institutional investors and sell-side analysts in New York City beginning at 9:00 a.m. eastern time on Thursday, February 12, 2015. At the Investor Day, members of the Company's senior leadership team will review Gartner's business portfolio, strategy for growth and financial performance. The Investor Day i