另外，请教这三份期刊的论文来源情况，美国的大概占多少比例？

都是吧

Journal of Accounting and Economics
The Journal of Accounting and Economics encourages the application of economic theory to the explanation of accounting phenomena. It provides a forum for the publication of the highest quality manuscripts which employ economic analyses of accounting problems. A wide range of methodologies and topics are encouraged and covered:
* The role of accounting within the firm;
* The information content and role of accounting numbers in capital markets;
* The role of accounting in financial contracts and in monitoring agency relationships;
* The determination of accounting standards;
* Government regulation of corporate disclosure and/or the Accounting profession;
* The theory of the accounting firm.

Journal of Accounting and Economics Editorial Board
Editors
R.L. Watts
Sloan School of Management, Massachusetts Institute of Technology (MIT), 50 Memorial Drive, Cambridge, MA 02142, USA

J. L. Zimmerman
William E. Simon Graduate School of Business Administration, University of Rochester, Rochester, New York, NY 14627, USA

R.W. Holthausen
University of Pennsylvania Wharton School, 3730 Walnut Street Philadelphia, PA 19104, USA

S.P. Kothari
Sloan School of Management, Massachusetts Institute of Technology (MIT), 50 Memorial Drive, Cambridge, MA 02142, USA

J. Core
School of Management, Massachusetts Institute of Technology (MIT), 100 Main Street, E62-670, Cambridge, 02142, USA

M. Hanlon
Sloan School of Management, Massachusetts Institute of Technology (MIT), 50 Memorial Drive, Cambridge, MA 02142, USA

W.R. Guay
University of Pennsylvania Wharton School, 2400 Steinberg-Dietrich Hall, Philadelphia, 19104-6365, USA

Editorial Assistant
G.L. Pratt
University of Rochester, New York, NY, USA

Associate Editors
C. Armstrong
University of Pennsylvania Wharton School, Philadelphia, PA, USA

M. Barth
Stanford University, Stanford, CA, USA

S. Basu
Temple University, Philadelphia, PA, USA

A. Beatty
Ohio State University, Columbus, OH, USA

A. Beyer
Stanford University, Stanford, CA, USA

M. Bradshaw
Boston College, Chestnut Hill, MA, USA

B.J. Bushee
University of Pennsylvania Wharton School, Philadelphia, PA, USA

D. Cohen
University of Texas at Dallas, Richardson, USA

M. DeFond
University of Southern California (USC), Los Angeles, CA, USA

R.A. Dye
Northwestern University, Evanston, IL, USA

P. Fischer
Pennsylvania State University, University Park, PA, USA

R. Frankel
Washington University in St. Louis, St Louis, MO, USA

R. Hayes
University of Utah, Salt Lake City, UT, USA

S. Heitzman
University of Rochester, New York, NY, USA

S. Huddart
Pennsylvania State University, University Park, PA, USA

M. Khan
University of Minnesota, Minneapolis, MN, USA

M. Lang
University of North Carolina at Chapel Hill, Chapel Hill, NC, USA

D. Larcker
Stanford University, Stanford, CA, USA

E.L. Maydew
University of North Carolina School of Medicine, Chapel Hill, NC, USA

G. Miller
University of Michigan, Ann Arbor, MI, USA

S. Rajgopal
Emory University, Atlanta, GA, USA

K. Ramanna
Harvard University, Boston, MA, USA

S. Roychowdhury
Boston College, Chestnut Hill, MA, USA

T. Rusticus
Northwestern University, Evanston, IL, USA

C.M. Schrand
University of Pennsylvania Wharton School, Philadelphia, PA, USA

R. Verdi
Massachusetts Institute of Technology (MIT), Cambridge, MA, USA

R.E. Verrecchia
University of Pennsylvania Wharton School, Philadelphia, PA, USA

C. Wasley
University of Rochester, New York, NY, USA

J.P. Weber
Massachusetts Institute of Technology (MIT), Cambridge, MA, USA

J. Wu
University of Rochester, New York, NY, USA

P. Wysocki
University of Miami, Coral Gables, FL, USA