you can follow the New Economic Geography model developed in

Fujita, M., P. R. Krugman, and A. J. Venables (1999), “The Spatial Economy: Cities, Regions and International Trade”, MIT Press.

Thank you for your advice

Some good papers that may help you and worth take a look at:

JAMES E. RAUCH - Productivty gains from geographic concentration of human capital: evidence from the cities. (1991)

CHRISTOPHER H. WHEELER - Evidence on agglomeration economies, diseconomies and growth (2003)

GLENN ELLISON; EDWARD L. GLAESER - The geographic concentrarion of industry: does natural advantage explain agglomeration. (1999)

GLAESER, KALLAL, SCHEINKMAN, SHLEIFER - Growth in cities (1992)

WILLIAM C. WHEATON; MARK J. LEWIS - Urban wages and labor market agglomeration (2002)

You can think on agglomeration as positive externalities that may come with specialization/localization (Marshall) or diversification/urbanization (Jacobs).

An entire awesome section on this issue - Oxford Handbook of Economic Geography. Helped me a lot.

Look at Zipf's law-We did it for Karnataka, India - have a look at this conference proceedings.

http://sinfras.com/conferences/nginfra2011/files/2011/12/An-approach-to-regional-planning-in-India.pdf

I want to examine regional development from a sectoral perspective using New economic geography theory. I am alsointerseted in inter-regional mogration. does NEG apply to agricultural sector or if it doesnot apply, then should I restrict to manufacturing and services only? Likewise, for migration , should I consider only industrial migration?

I am offering you this: European Spatial Planning Observatory Network

(http://www.espon.eu/main/Menu_Publications/Menu_ESPON2006Publications/)

This is an organization comes from an Interreg project, and measures territorial disparities. It has quite good methodolgy.

Accompanying journal is this: European Journal of Spatial Development (http://www.nordregio.se/EJSD/)

Thank you Mr Cassiano Dalberto for your advice

Thanks Mr Lengyel

The work on Paul Romer in his advancement of the idea of Charter Cities, he cites the disparities that are obvious even from satellite images of regions

http://www.ted.com/talks/paul_romer?language=en

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