A new study from the University of Chicago suggests city residents aren't getting enough play, to the detriment of their communities and cultural institutions. Between later marriage, the prevalence of divorce, and domestic violence, Chicagoans spend about half their lives single and half of their single lives alone. Researchers also found neighborhood, ethnicity, sexual preference and friends could significantly limit people's sexual behavior. Research leader Edward O. Laumann -- hailed as "the new Kinsey" for his studies of modern sexual health -- will release a book on his findings in the spring. [Trib login: gapers/gapers]