3.1. Sample Selection and Data Sources
This study employs a firm-level unbalanced panel dataset of 200 non-financial companies listed in Gulf Cooperation Council (GCC) countries, including Saudi Arabia, the United Arab Emirates, Qatar, Kuwait, Oman, and Bahrain. The sample period spans from 2015 to 2024, a decade characterized by rapid digital transformation in the region.
Table 1 presents the distribution of the sample across GCC countries, including the number of firms and firm-year observations.
The final sample consists of 1820 firm-year observations, corresponding to an average of 9.1 observations per firm.
The panel is unbalanced because not all firms are observed continuously throughout the sample period. This situation arises primarily from differences in listing dates across firms, occasional gaps in financial reporting, and the limited availability of information required to construct the digitalization and e-commerce capability indices, particularly for intangible assets and research and development expenditures. Rather than restricting the analysis to a balanced sample, all available firm-year observations meeting the data requirements were retained. This approach preserves a larger cross-sectional dimension and is consistent with common practice in firm-level panel studies.
The sample includes firms from a broad range of non-financial industries across GCC economies. Manufacturing firms represent the largest group (42 firms), followed by consumer goods and services (38 firms), industrial firms (34 firms), and real estate and construction companies (26 firms). The sample also includes firms operating in energy and utilities (18 firms), telecommunications (14 firms), healthcare (10 firms), technology (8 firms), and other non-financial sectors (10 firms). This sectoral diversity enhances the representativeness of the sample and allows the analysis to capture digitalization and e-commerce dynamics across different business environments. Because the empirical models include firm-fixed effects, time-invariant sectoral characteristics are absorbed by the estimation framework, thereby mitigating potential bias arising from industry-specific heterogeneity.
Firm-level financial data are obtained from Datastream, complemented by information from firms’ annual financial reports where necessary, particularly for variables related to intangible assets and research and development (R&D) expenditures. Financial institutions are excluded due to their specific regulatory environment and distinct financial structure. To operationalize the empirical analysis, the following subsection defines the variables used in this study.
3.2. Variable Definition and Measurement
The dependent variable is firm value, proxied by Tobin’s Q, defined as the ratio of the market value of equity plus total debt to total assets. As a robustness check, firm performance is alternatively measured using return on assets (ROA).
The key explanatory variable is firm-level digitalization (DIG), an index constructed to capture firms’ digital transformation efforts. Digitalization refers to the extent to which firms develop, adopt, and integrate digital technologies into their organizational processes, innovation activities, and value creation mechanisms. Consistent with the resource-based view, digitalization can be viewed as a strategic capability that enables firms to improve information processing, operational efficiency, innovation, and market responsiveness. Because direct firm-level measures of digital transformation are generally unavailable for large samples of listed GCC firms over long periods, this study adopts an accounting-based approach frequently used in the literature to capture firms’ digital investment intensity. Specifically, digitalization is proxied through indicators reflecting firms’ investments in intangible technological resources and innovation activities. Intangible assets capture investments in software, digital platforms, databases, and other technology-related assets, while research and development expenditures reflect firms’ efforts to develop new technological capabilities and digital innovations. Together, these variables provide a reasonable approximation of firms’ underlying level of digital transformation and technological readiness. The second main explanatory variable is E-commerce capability (ECC), an index which reflects firms’ operational ability to leverage digital technologies in commercial activities.
Control variables include firm size (natural logarithm of total assets), leverage (total debt to total assets), profitability (ROA), and growth opportunities (market-to-book ratio). Industry and year dummy variables are included to control for sector-specific effects and macroeconomic shocks.
Table 2 summarizes all the variables used in this research.
3.3. Construction of Digitalization (DIG) and E-Commerce Capability (ECC) Indices
To capture the multidimensional nature of digital transformation and operational digital capability, this study constructs composite indices for digitalization (DIG) and e-commerce capability (ECC) using principal component analysis (PCA).
Digitalization (DIG) is measured based on firm-level indicators reflecting investments in digital and technological resources, including intangible asset intensity and research and development (R&D) intensity. These variables capture firms’ engagement in digital infrastructure, innovation activities, and technology adoption.
The selection of intangible asset intensity and R&D intensity is motivated by both theoretical and empirical considerations. From a theoretical perspective, digital transformation requires investments in knowledge-based assets, software systems, technological infrastructure, and innovation capabilities that facilitate the integration of digital technologies into business operations. Empirically, prior studies frequently employ intangible assets and innovation-related expenditures as proxies for firms’ technological capability and digital development when direct measures of digitalization are unavailable. These indicators are particularly suitable in the GCC context, where standardized firm-level disclosures on digital adoption remain limited. Consequently, the constructed index is intended to capture firms’ relative degree of digital readiness and digital investment intensity rather than specific digital technologies or platforms.
E-commerce capability (ECC) is constructed using indicators reflecting firms’ ability to leverage digital technologies in commercial activities, including sales growth and asset turnover. These variables represent firms’ operational performance in digitally mediated environments and their ability to scale and efficiently utilize resources.
The selection of sales growth and asset turnover is motivated by both theoretical and empirical considerations. From a theoretical perspective, firms with stronger e-commerce capabilities are expected to expand market reach, improve customer acquisition, and utilize digital channels to increase sales. At the same time, effective integration of digital technologies may enhance operational efficiency and resource utilization, which are reflected in higher asset turnover. Empirically, direct firm-level measures of e-commerce capability are rarely available for large cross-country samples, particularly in emerging markets and GCC economies. Consequently, prior research frequently relies on observable performance indicators associated with firms’ ability to exploit digital commercial opportunities. Accordingly, the constructed index captures realized e-commerce capability and digital commercial effectiveness rather than direct technological adoption itself.
Prior to applying PCA, all variables are standardized to ensure comparability and to eliminate scale effects. PCA is then employed to extract the common variation among the selected indicators. The first principal component is retained as the composite index, as it captures the largest proportion of variance in the data.
These composite indices are subsequently used in the empirical analysis as key explanatory variables, with digitalization (DIG) also serving as the threshold variable in the nonlinear regression models.
Table 3 reports the results of the principal component analysis used to construct the digitalization and e-commerce capability indices.
To further evaluate the adequacy of the selected variables for principal component analysis, additional diagnostic tests were performed.
Table 4 reports the Kaiser–Meyer–Olkin (KMO) measure and Bartlett’s test of sphericity for the constructed indices.
To assess the suitability of the selected variables for principal component analysis, Kaiser–Meyer–Olkin (KMO) measures and Bartlett’s tests of sphericity were performed. The KMO statistics exceeded the commonly accepted threshold of 0.50, while Bartlett’s tests rejected the null hypothesis of an identity correlation matrix, supporting the application of PCA. Because each index is constructed from only two underlying indicators, the first principal component is expected to capture a substantial share of the total variance. Accordingly, the relatively high explained variance reported for the digitalization and e-commerce capability indices reflects the strong common variation between the selected indicators rather than overfitting. Furthermore, factor rotation was not applied because only a single principal component was retained for each index.
The results of the principal component analysis confirm the validity of the constructed indices for digitalization and e-commerce capability. For the digitalization index (DIG), both intangible asset intensity and R&D intensity load positively on the first principal component, with loadings of 0.68 and 0.62, respectively. This indicates that these variables capture a common underlying dimension of firm-level digital transformation. The first component explains 92% of the total variance, suggesting that it provides a strong and representative measure of digitalization.
Similarly, the e-commerce capability index (ECC) exhibits positive loadings for sales growth and asset turnover, with values of 0.64 and 0.59, respectively. These results indicate that both variables jointly reflect firms’ operational ability to leverage digital technologies in commercial activities. The first principal component explains 83% of the total variance, confirming that the index captures a substantial share of variation in e-commerce capability.
In sum, the PCA results support the use of DIG and ECC as reliable composite indicators, as they summarize the common variation among their respective components and reduce potential multicollinearity in subsequent regressions. Although these proxies do not capture all dimensions of digitalization, they provide a consistent and widely used approximation of firms’ digital investment intensity.