## 4 Results
### Nonlinear and Interaction Effects  
Partial Dependence Plots (PDPs) were created for broadband access, ICT specialists, and GDP per capita in addition to a 2D interaction plot for broadband and ICT specialists in order to better understand how key variables affect cloud adoption. Nonlinear linkages and interaction effects that are not immediately visible from normal variable significance measures are revealed by these visualizations. Figure 5 illustrates the substantial positive correlation between cloud use and broadband access. The PDP reveals a nonlinear trend: cloud adoption is still muted at very low broadband connection levels (standardized values below \(-1\)). The anticipated cloud adoption rate, however, rises dramatically as internet availability gets closer to average (about 0), plateauing at higher broadband levels. This implies that increasing broadband infrastructure above a particular point accelerates the adoption of cloud computing. Figure 6 illustrates the relationship between ICT specialists and cloud adoption. The PDP reveals a strong, consistently positive relationship: as the share of ICT specialists increases, the predicted cloud adoption rate rises steadily, with no evident plateau. This trend underscores the critical role of digital workforce skills in facilitating cloud transformation across EU countries. There is a complicated, nonlinear link between GDP per capita and PDP (Figure 7). Initially, cloud adoption decreases significantly as GDP per capita rises from low levels (below 0); this seems contradictory and may indicate that cloud adoption is initially influenced more by digital readiness than by economic circumstance alone. Cloud use, however, starts to rise quickly as GDP per capita surpasses average levels (about 1), indicating that  
Figure 4: SHAP summary plot for the tuned Random Forest model (without country dummies), showing the relative impact of features on predicted cloud adoption. (Panel A: 2014–2021). Source: Authors’ estimations in R software. wealthier economies undergo a stronger push toward digital transformation provided specific baseline criteria are satisfied. The interaction between broadband access and ICT specialists is visualized in Figure 8. The contour plot reveals that cloud adoption is highest when both broadband access and ICT specialist density are high (top-right corner of the plot). On the other hand, the lowest anticipated cloud adoption is seen in regions with low internet and ICT levels (bottom-left). It is interesting to  
Figure 5: Partial Dependence Plot of Broadband Access \(\rightarrow\) Cloud Adoption. Source: Authors’ estimations in R software. Figure 6: Partial Dependence Plot of ICT Specialists \(\rightarrow\) Cloud Adoption. Source: Authors’ estimations in R software. Figure 7: Partial Dependence Plot of GDP per Capita \(\rightarrow\) Cloud Adoption. Source: Authors’ estimations in R software. note that the relationship is nonlinear and synergistic: while increases in either component result in modest gains, increasing both broadband access and ICT capacity has a far greater overall impact, indicating that digital infrastructure and digital skills complement each other. To further support the presence of nonlinear dependencies and conditional effects, we computed global feature interaction strengths using [PERSON]'s \(H\)-statistic, implemented via the Interaction$new() method in the iml package. This diagnostic quantifies how strongly each variable's effect on the outcome depends on interactions with other features. As shown in Figure 9, ICT specialists and broadband access exhibit the highest interaction strengths, indicating their predictive effects are not purely additive but conditional on other structural features. Other predictors such as GDP per capita and higher education also demonstrate notable interaction behavior. These findings reinforce earlier SHAP and PDP visualizations, emphasizing that cloud adoption in the EU arises from nonlinear, complementary relationships between human capital and digital infrastructure.