From the UCD web site
Economics:
The study of economics is the study of choices. How should a society choose to allocate and distribute its resources? Which needs should have the highest priority, and which are less important? Economists study how people use their limited resources in an attempt to satisfy their unlimited wants. They create scientific models to explain why people behave the way they do, and use these models along with observations of the world to analyze and explain why things happen the way they do. Based on this knowledge, they propose solutions to problems that may at first seem surprising, but that prove to work well in practice. Economists work in all areas of government and industry, in positions ranging from stock market analysis to sports marketing and banking regulation.
Economics
Managerial Economics:
The managerial economics major at UC Davis goes beyond the limits of traditional economics and business majors, blending a thorough grounding in economic theory with business knowledge and applications. You will specialize in at least one of three options: managerial economics, which focuses on evaluating, financing and managing business activities; environmental and resource economics, which focuses on issues related to use of resources and environmental quality; or agricultural economics, which focuses on the business aspects of producing and marketing foods and fibers. The real-world focus of this major provides ideal preparation for transition into the business world or to postgraduate business administration programs.
Managerial Economics