# Getting started

## What is concstats?

concstats is a small package that helps you to calculate the structure, concentration or diversity measures of a given market. You can reach that goal in different ways:
a) calculating an individual measure, e.g. the Herfindahl Hirschmann Index (HHI) or its dual.
b) calculating a group of measures, e.g. structural measures, or
c) a selected set of measures in a one-step procedure.

## How can you install it?

To install the latest development version of concstats directly from GitHub or use:

library(devtools)
devtools::install_github("schneiderpy/concstats")

# Why did I build it?

Measures of concentration and competition are important and give a first insight of a given market structure in a particular market. They are important to determine public policies and strategic corporate decisions. However, in research and in practice the most commonly used measure is the Herfindahl Hirschman Index. The concstats package offers a set of alternative measures.

concstats allows you to calculate quickly a particular measure or a group of measures to give you a better overview of a given market situation and therefore reducing uncertainty. It can be used by practitioners and academics alike.

## How can it be used?

concstats should be used by practitioners and academics who are concerned about a given market situation regarding its structure, concentration, diversity or inequality. A single standard measure like the Herfindahl Hirschmann Index (HHI) may lead to erroneous conclusions. The concstats package offers a straightforward way to calculate standard and alternative measures given a data set of market participants and their participation (in absolute or relative values) in a particular market at a given point of time or over time. concstats provides currently the following basic functions:

• concstats calculates eight pre-selected measures in a one-step procedure to provide a first insight of the market.
• mstruct is a wrapper for the following measures: firm, nrs_eq (Numbers equivalent), top, top 3 and top 5 market share, and all calculates all measures as a group.
• comp is a group wrapper for the following concentration measures: hhi, the dual of the hhi, the min. of the hhi, the dominance index, the stenbacka index, and finally all which calculates all measures as a group.
• inequ is a wrapper for inequality and diversity measures and contains: entropy, gini coefficient, simpson index, the palma ratio and the alternative grs measure, all calculates the group measures.