In social marketing, the Boomerang Effect occurs as a result of attempted attitude change. If someone makes a strong attempt to change a prospect's attitude toward a subject, the prospect will counter with an equally strong response, even if prior to the confrontation, the prospect held a weak attitude toward the subject.

In sports marketing the boomerang effect refers to the methodology for the measurement of sponsorship return on investment. This article or section does not adequately cite its references or sources. ... Sponsorship can refer to several concepts: A sponsors support of an event, activity, person, or organization. ... In finance, the return on investment (ROI) or just return is a calculation used to determine whether a proposed investment is wise, and how well it will repay the investor. ...

The Boomerang Effect has three distinct parts:

Investment

refers to a client’s initial investment in a sponsorship or promotion of a sports property

Activation

is the work that is done to execute the investment and make the sponsorship or promotion known and draw public interest

Returns

are the increase in either traffic or income, or both, to the client due to their investment

The quality of the investment and activation are the variables that drive the returns. Ultimately, return on investment is calculated as the net profit attributable to the investment less the cost of the investment and activation, divided by the cost of the investment and activation.

The following equation is the basic mathematic explanation of the Boomerang Effect: