# The Impact of Information Systems Implementation in the Greek Manufacturing Enterprises
## 4 Results and Discussion
### Level of Profitability--Impact and Contribution of IS Adoption  
In the current section, the Mann-Whitney two-sample U-test is used to assess differences between two distinct groups that are described accordingly, regarding the impact of IS adoption and the contribution of IS adoption that were measured on the five-point Likert scale. The nonparametric test, which was mentioned above, is considered as particularly powerful for analyzing data collected in a mail survey [37]. When the \(p\)-value is lower than 0.05, the U-tests indicate a significant differences between the respective two groups in each case. Otherwise, the U-tests indicate that the respective null hypothesis of no difference cannot be rejected at significance lower than 0.05 percent.  
Based on the H4 hypothesis that the profitability of a company is positively affected by the use of IS, two prominent different groups of companies were initially identified regarding the level of profitability they were lead: those which consider that their companies manage to obtain high level of profitability due to IS adoption (IS1 = \(n_{1}\) = 36) and those that obtained a medium level of profitability due to IS adoption (IS2 = \(n_{2}\)= 40) [34]. According to authors in [27], if the management chooses to implement SCM, the performance of Indian SMEs can be improved on several issues including financial issues. Through this research, there is an effort to assess whether there are statistically significant differences between the two groups posing the hypotheses H5a and H5b.  
According to the results that are shown in Figure 5, the hypothesis (H5a) of significant differences between the two groups (IS1 and IS2) according to the Mann-Whitney \(U-\)tests that were conducted is verified in: \"Production management\" (\(p\)-value = 0.021), Distribution network management (\(p\)-value = 0.015), Warehouse management (\(p\)-value = 0.018), and Customer service (\(p\)-value = 0.029). That means that there is a reason that IS1 companies have better average ratings compared to IS2 companies in these variables. It seems that better management in those areas led to higher profitability. There is no difference between the two groups in regards of the rest variables--Supply management and Inventory management--since the \(p\)-value for both is higher than 0.05, which means that the two groups were affected in a similar way by the IS implementation regarding these two variables.  
Figure 4: Contribution of IS adoption.  
At first glance by looking at Figure 6, it is notable that high profitability is followed by a better average rating in every respective row of the table. Although with a closer look at the table and specifically the \(p\)-value, it is understandable that the hypothesis is not valid for every single one of the questionable elements. Production process, Returned product reduction, Relationship with the suppliers, Cost reduction and faster Customer service all have a \(p\)-value that is higher than 0.05. That means that although ISI companies have better average ratings than IS2 on those 5 elements, yet there is no significant statistical difference between these two groups, which means that they are not making such a difference that would lead in significantly higher profitability. On the other hand, there is statistically significant difference between ISI and IS2 companies in Competitive advantage (\(p\)-value = 0.007) and Maintain clientele (\(p\)-value = 0.023), which means that the higher profitability might be a result of those companies do better in these two areas.