HHI-Methods: Methods For Calculating the Herfindahl-Hirschman Index

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Methods For Calculating the Herfindahl-Hirschman Index

Description

Computes the Herfindahl-Hirschman Index (HHI) using simulated market shares and either pre- or post-merger ownership information. Outside shares are excluded from the calculation.

Usage

## S4 method for signature 'Bertrand'
hhi(object, preMerger = TRUE, revenue = FALSE, insideonly = TRUE)

## S4 method for signature 'Cournot'
hhi(object, preMerger = TRUE, revenue = FALSE)

## S4 method for signature 'VertBargBertLogit'
hhi(object, preMerger = TRUE, revenue = FALSE, insideonly = TRUE)

Arguments

object	An instance of one of the classes listed above.
preMerger	If TRUE, returns pre-merger outcome. If FALSE, returns post-merger outcome. Default is TRUE.
revenue	If TRUE, returns revenues. If FALSE, returns quantities. Default is TRUE.
insideonly	If TRUE, excludes the share of the outside good from the calculation. Default is TRUE.

antitrust documentation built on Aug. 24, 2022, 9:05 a.m.