Thanks for the good answers and start a good discussion.

Would love clarify the issue.

As mathematically possible to write the term "cluster" in the economy.

Are there any relevant publications.

We can start from the Porter definition: “geographic concentrations of interconnected companies, specialized suppliers, services providers, firms in related industries, training institutions and support organizations linked around technologies or end product within a local area or region” (Porter, 1990). There is also a "formal definition" of the Eu commission really similar to the Porter definition (regulation on state aid on research): "'innovation clusters means structures ororganisedgroups of independentundertakings (such as innovative start-ups, small, medium and large undertakings, as well as research and knowledge dissemination organisations,non-for-

profit organisations and other related economic actors) designed to stimulate innovative activity by promoting sharing of facilities and exchange of knowledge and expertise and by contributing effectively to knowledge transfer, networking information dissemination and collaboration among the undertakings and other organisations in the cluster ". A different approach could be to intepret clusters as Value network activities (C. PArolini): is a "new way" to intepret value chains across borders ....To be honest I prefers territorial sectorial ecosystems instead clusters......

@Fabrizio Conicella, very well introduced the concept. I have a question, "geographic concentrations of interconnected companies" is it still a valid definition. I think (may be wrong) that the term "interconnected" overrides the concept "geographic concentrations or saturation"

god point........first of all more and more territorial clusters are covering only part of the "global value chains"this is particularly happening in high tech sectors...so the concept of concentration has to be probably revised..........but returning to Your point...it is not enough to have a huge amount of companies working in a specific sector but such companies have to be networked (such as in a community). from such point of view probably is more important to have a System then a simple number related to companies present in a specific territory..Having a systems means that there are relations between system members.....

I fully agree with Fabrizio. In fact, Michael Porter published THE COMPETITIVE ADVANTAGE OF NATIONS in 1990. It examines as how national policies of countries, states, regions and cities can get competitive advantage in a strained global economy. Clustering is a strategy to turn a sluggishly growing economy into a competitive one. Clustering is not only limited to clustering of interrelated firms and business, but also clustering of interrelated industries, that is, geographic concentrations of interconnected industries and supporting organizations. For that reason, the governments should establish an industry cluster program that stimulates the collaborative interactions of firms and supporting organizations in regional economies to produce more commercial innovation and higher wage employment. In recent years, “cluster strategies” have become a popular economic development approach among state and local policymakers and economic development practitioners. Cluster analysis can help diagnose a region’s economic strengths and challenges and identify realistic ways to shape the region’s economic future. Since, a cluster of firms, business and other interactive and supporting organisation, therefore, a regional cluster is characterised with diversity of human resources, therefore each cluster is capable of absorbing economic shocks. It can be compared, in a way, with cropping diversity and crop specialisation in agricultural sector. An outbreak of pests or disease or bad crop season may destroy an entire crop in a region of specialised cropping, while in the diversified cropping, some will be there to harvest and eat.

Thank You Mhammad...i will add to your comment that clusters are increasing the resilience of a territory on extenal shocks..in such perspective they are an interesting tool in the hands of public policies......the real problem is the evaluation of outcomes of such policied and impact..it takes time..in europe is exosting a pan european initiative 8European Secretariat for cluster analisys) that is standardising the bencjmarking and evaluation of cluster initiative.......

Some definitions:

http://en.wikipedia.org/wiki/Business_cluster

http://www.isc.hbs.edu/competitiveness-economic-development/frameworks-and-key-concepts/Pages/clusters.aspx

An example is Eurozone.

Thanks for the good answers and start a good discussion.

Would love clarify the issue.

As mathematically possible to write the term "cluster" in the economy.

Are there any relevant publications.

@Fabrizio Conicella, thanks for your kind and quick reply. Let us continue learning from each other.

A cluster is a group of companies sharing local resources, using similar technologies, and forming linkages and alliances. These linkages can take the form of buyer-supplier relationships, turnover and "pirating" of employees, joint marketing, training, or research initiatives, associations, and lobbying. One of the unique features of cluster analysis is the focus on linkages between firms, and on implications for shared strategies – often called "Co-opetition" – in which companies selectively compete in some respects (say, in output markets) yet cooperate in other respects (say joint training programs).

See more details at the link:

http://www.ecgroup.com/methodology/cluster.htm

http://www.ecgroup.com/images/regional_goals.gif

Clusters are a powerful tool for policy action and framework for economic development. The concept of cluster in the economy is different from the concept of cluster in biology and health sciences, in engineering, or in Art.

The concept of cluster in the economy can be defined, according to Harvard Business School, as follows: A cluster is a geographic concentration of related companies, organizations, and institutions in a particular field that can be present in a region, state, or nation. Clusters arise because they raise a company's productivity, which is influenced by local assets and the presence of like firms, institutions, and infrastructure that surround it. This means critical masses in one place of linked industries and institutions--from suppliers to universities to government agencies--that enjoy unusual competitive success in a particular field.

Cluster increase productivity and operational efficiency, stimulate and enable innovation and facilitate commercialization and new business formation.

Clusters foster high levels of productivity and innovation and lays out the implications for competitive strategy and economic policy:

Clusters affect competition in three broad ways: first, by increasing the productivity of companies based in the area; second, by driving the direction and pace of innovation; and third, by stimulating the formation of new businesses within the cluster:

Dear Vyacheslav Lyashenko

I am not an expert in economy. But clusters are geographic concentrations of interconnected companies and institutions in a particular domain. Clusters help to utilize synergy by having collaboration among the participants.

Here is a document about Cluster Based Economic Development: A Comprehensive Strategy to Secure NW Ohio’s Economic Future

http://uac.utoledo.edu/nwoerc/NWOH-Cluster-Overview.pdf

Here is a Harvard Business Review paper on clusters.

http://www.rimisp.org/wp-content/uploads/2012/07/31_rimisp_Cardumen.pdf

Dear Nageswara Rao Posinasetti thanks for the answer.

http://www.ecgroup.com/methodology/cluster.htm

https://www.hbs.edu/faculty/Publication%20Files/DTI_London_2004.03.16_6d889060-4a92-4e60-9dab-8febde62e3a8.pdf

https://www.clustermapping.us/sites/default/files/files/resource/From_clusters_to_cluster-based_economic_development.pdf

http://www.value-chains.org/dyn/bds/docs/712/The_Cluster_Approach_to_Economic_Growth.pdf

https://www.clustercollaboration.eu/sites/default/files/eu_initiatives/cluster-based_local_economic_development_in_the_context_of_ris3_mrivas.pdf

https://gwipp.gwu.edu/sites/g/files/zaxdzs2181/f/downloads/Working_Paper_042_Clusters.pdf

Dear Hamit, Thanks for your reply.