This study, cosponsored by Irvine, the William and Flora Hewlett Foundation, and Leveraging Investments in Creativity, shows how California artists move more fluidly between the commercial, nonprofit and community sectors than is commonly believed. Their ability to do so, the study concludes, is a major stimulant to regional economic activity and the quality of life. The study, by the University of Minnesota’s Humphrey Institute of Public Affairs, is based on a Web survey of Los Angeles and San Francisco Bay area musicians, writers, and performing and visual artists. With New York, these two regions support more artists per capita than the nation’s other large metropolitan areas.