Impact Index is a term used across several distinct fields, each referring to a different quantitative or statistical measure. The most prominent and widely documented use of the term is in the context of cricket analytics, but it also appears in environmental science, impact investing, and health research.
Cricket Analytics
The most notable and best-documented use of "Impact Index" is an alternative statistical system in cricket. It was conceived by Indian filmmaker and writer Jaideep Varma in March 2009 and unveiled in July of that year at the ICC Centenary Conference at Oxford.
The system measures each player's contribution in the context of the impact he has on a match, as opposed to traditional cricket statistics such as batting average, bowling average, or strike rate. It compares each player's performance relative to the other 21 players in the match. For career assessments, it places higher value on performances that affect the series or tournament result for the player's team.
Key milestones in the system's history include:
- In 2010, the T20 version of Impact Index served as the "Official Stats Partner" for the Radiant Twenty20 USA tournament in the United States, and the system was used to award all individual tournament honors.
- In January 2011, when applied over the history of One Day International (ODI) cricket, it determined that Viv Richards was the greatest ODI player of all time—a conclusion ESPNCricinfo independently reached through its own studies six years later.
- It became the first (and, as of the time of reporting, only) analytics system to be mentioned in the Wisden Almanack (in 2012).
- In June 2014, Impact Index became part of Fidelis World and a sister company of Wisden India, operating from Bangalore.
- In February 2017, Impact Index released its first book, Numbers Do Lie: 61 Hidden Cricket Stories, co-written with Aakash Chopra and published by HarperCollins.
The system has been covered by The Times of India, BBC World Service, NDTV, ESPNCricinfo, Star Sports, Forbes, CNBC, and other publications.
Environmental Science
In environmental engineering and process design, an "impact index" is defined as a quantitative measure representing the potential environmental impact of mass and energy emissions on the ecosystem. It is evaluated in units of Potential Environmental Impact Index (PEI) per kilogram of product. This metric allows for the comparison of different process alternatives based on their environmental impact.
Impact Investing
The term is also used in the field of impact investing:
- SVX Impact Index: A directory of impact investment offerings available to Canadian accredited investors, asset owners, and portfolio managers. It features over 200 impact investment opportunities and includes a curated subset called "Impact Index+," which contains offerings vetted for strict impact, governance, and financial standards.
- SerenityShares Impact Index: A public equity benchmark (ticker: ICANNDX, NYSE) that employs a passive methodology to measure the performance of a diversified portfolio of U.S.-listed companies operating in areas that address societal, social, and environmental challenges. It uses a solutions-first approach aligned with the UN Sustainable Development Goals, organized around six pillars and twenty themes.
Health Sciences
In health research, an "impact index" can be used to measure the effect of specific factors on quality of life or health outcomes. For example, in some studies it has been used to measure the effect of urinary incontinence on women's quality of life.
Summary
Because "Impact Index" is used across multiple disciplines with different meanings, its precise definition depends on the context in which it appears. The cricket analytics system is the most extensively documented and widely recognized use of the term, with dedicated encyclopedic coverage.
