MARKET POWER AND THE ADJUSTED CONCENTRATION INDEX

Bu çalışma, piyasa gücü ve konsantrasyon oranını ölçmek amacıyla, Herfindahl ve Dominans Endekslerine benzer fakat hem basit ve ölçeklenebilir hem de böyle bir endeksten beklenen tüm istenen özellikleri üzerinde taşıyan bir endeks tanımlamayı amaçlamaktadır. Endeksin, firma sayısı ile negatif, firmaların piyasa paylarının varyansıyla pozitif orantılı olması gerekmektedir. Amerikan endüstrisinden alınan örneklere ek olarak, alternatif endeksimizden yola çıkarak, piyasa paylarının servet üzerindeki etkilerini formülize etmekteyiz. Diğer yandan, teknolojik gelişmeler ve talep esnekliği, bu çalışmanın kapsamının dışında kalmaktadır.

Anahtar Kelimeler:

Piyasa Gücü, Konsantrasyon Oranı, Hirschman-Herfindahl Endeksi

MARKET POWER AND THE ADJUSTED CONCENTRATION INDEX

This study aims to define an alternative index to measure market power and concentration ratio, similar to the Herfindahl Index and the Dominance Index in terms of ease, as a simple and scalable but more consistent scalar number carrying all the desired properties from such an index, which should be negatively correlated with the number of firms and positively correlated with the variance of firm market shares. In addition to examples from the US industries, based on the alternative index, we also formulate the impact of market concentration on welfare. The impact of technological progress and demand elasticity on market power however is not addressed in this study.

Keywords:

Market Power, Concentration Ratio, Hirschman-Herfindahl Index,

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