Wooldridge, Jeffrey M., 1960- Introductory econometrics : a modern approach / Jeffrey M. Wooldridge - 3rd ed. - Mason, OH : Thomson/South-Western, 2006 - xxii, 890 p. : ill. ; 24 cm. Includes bibliographical references (p. 854-858) and index ISBN: 0324289782 RM472.14 Subjects--Topical Terms: Econometrics