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In general, return on investment (ROI) is a widely used financial metric that measures the efficiency of an investment by calculating the ratio of the investment's net gains or losses to its total cost. A positive ROI indicates that the investment has generated more revenue or profit than its cost, while a negative ROI indicates that the investment has generated less revenue or profit than its cost.Empirical studies on ROI seek to analyze the factors that influence the ROI of different types of investments in various contexts, as well as the effectiveness of different methods for measuring ROI. Such studies can provide valuable insights for investors, policymakers, and business leaders seeking to make informed decisions about investment strategies.
Haleblian, Devers, McNamara, Carpenter, and Davison (2009) conducted a meta-analysis of 101 studies on human resource management (HRM) practices and their impact on firm performance. They found that there was a significant positive relationship between HRM practices and firm performance.Liu and Wei (2010) examined the relationship between investment in research and development (R&D) and ROI in the pharmaceutical industry using the ex-post facto research design the study. The researchers found that R&D investment had a significant positive effect on ROI. Meanwhile, Winkler and Marxt (2015) analyzed the ROI of social media marketing for small and medium-sized enterprises (SMEs). The authors found that social media marketing had a positive effect on ROI, with a return of $2.56 for every $1 invested.
Rostami, Lashgari, and Rezaei (2017) studied the relationship between brand equity and return on investment (ROI)in the automotive industry. The authors reported that brand equity had a significant positive effect on ROI, with higher brand equity leading to higher ROI. In the same vein, Hockerts and Wüstenhagen (2010) conducted a meta-analysis of 66 studies on the financial performance of sustainable investing. The authors found that there was a positive relationship between sustainability and financial performance with sustainable investments outperforming traditional investments in the long term. Also, Cascio (1991) analyzed the return on investment (ROI) of different human resource (HR) programmes, such as selection and training, in organizations. The researcher found that HR programmes that were designed and implemented effectively could yield return on investments of up to 1000%.
These are just a few examples of empirical studies on return on investment (ROI) across different fields and industries. Overall, the literature suggests that ROI can be influenced by a variety of factors, including human resource management practices, research and development (R&D) investment, social media marketing, brand equity, and sustainability. Fundamentally, financial and marketing investment could be attributed to business performance. Ebrahim and Rangan (2010) conducted a study on the return on investment (ROI) of social investments, including microfinance, fair trade, and social entrepreneurship. They found that social investments had a positive ROI, with a return of up to 13% per year for some types of investments.
Similarly, Jorion and Goetzmann (1999) conducted a study on the return on investment (ROI) of different investment strategies in the stock market over a 70-year period. The researchers found that certain strategies, such as momentum investing and contrarian investing, yielded higher returns than others. On the other hands, Kumar, Petersen, and Leone (2007) examined the return on investment (ROI) of different marketing channels, including TV, print, and online advertising, for a consumer goods company. The authors found that online advertising had the highest ROI, followed by TV advertising and print advertising. Meanwhile, some researchers had argued on social and training investments as correlates of business performance. Schmidt, Hunter, and Outerbridge (1986) conducted a meta-analysis of 85 studies on the return on investment (ROI) based on training programmes in organizations. The researchers found that the average ROI for training programs was 14%, meaning that for every dollar invested in training, the organization gained an additional 14 cents in profit.