real strength than meets the eye." Views on technology In 1998 during the dot-com bubble, Krugman wrote a commentary for Red Herring that urged skepticism of optimistic predictions for technology-driven progress. He followed it with several pessimistic predictions of his own, including that "[b]y 2005 or so, it will become clear that the Internet's impact on the economy has been no greater than the fax machine's" and that the number of jobs for IT specialists would decelerate and turn down. In a 2013 interview, Krugman stated that the predictions were meant to be "fun and provocative, not to engage in careful forecasting". Krugman is a vocal critic of Bitcoin, arguing against its economic soundness since 2011. In 2017, he predicted that Bitcoin is a more obvious bubble than housing, and stated that "[t]here's been no demonstration yet that it actually is helpful in conducting economic transactions". Personal life Krugman has been married twice. His first wife, Robin L. Bergman, is a designer. He is currently married to Robin Wells, an academic economist who received her BA from the University of Chicago and her PhD from the University of California, Berkeley. She, as did Krugman, taught at MIT. Together, Krugman and his wife have collaborated on several economics textbooks. Although rumors began to circulate in early 2007 that Krugman's "son" was working for Hillary Clinton's campaign, Krugman reiterated in his New York Times op-ed column that he and his wife are childless. Krugman currently lives in New York City. Upon retiring from Princeton after fifteen years of teaching in June 2015, he addressed the issue in his column, stating that while he retains the utmost praise and respect for Princeton, he wishes to reside in New York City and hopes to focus more on public policy issues. He subsequently became a professor at the Graduate Center of the City University of New York and a distinguished scholar at the Graduate Center's Luxembourg Income Study Center. Krugman reports that he is a distant relative of conservative journalist David Frum. He has described himself as a "Loner. Ordinarily shy. Shy with individuals." Published works Academic books (authored or coauthored) The Spatial Economy – Cities, Regions and International Trade (July 1999), with Masahisa Fujita and Anthony Venables. MIT Press, The Self Organizing Economy (February 1996), EMU and the Regions (December 1995), with Guillermo de la Dehesa. Development, Geography, and Economic Theory (Ohlin Lectures) (September