Women-led private technology companies are more capital-efficient, achieve 35 percent higher return on investment, and, when venture-backed, bring in 12 percent higher revenue than male-owned tech companies. That’s according to new research presented at a recent conference in San Francisco organized by Women 2.0, a media company devoted to women founders in the tech industry. It indicates female entrepreneurs, who have traditionally lagged behind their male counterparts, are catching up, at least by some measures.Led by Vivek Wadhwa, who holds titles at Stanford and Duke universities, and Lesa Mitchell, a vice president at the Kauffman Foundation,