## 5 Discussion
We can reject the null hypothesis for the normal distribution at the 5% significance level. Because of that, we used non-parametric Kruskal-Wallis tests in Matlab for different testing scenarios because they are statistically independent. The results for p-value are given in Table 7.  
We can state that the testing scenario has no statistically significant impact on the gathered data because all \(p\)-values are higher than 0.05. Therefore, we can say that the route direction does not influence the gathered data as well as vehicle combinations and countries. Because the ax1000 \(p\)-value of 0.0634 is close to the decision limit, we provide the boxplots of the maximal values of the ay1000 of acceleration events for individual countries in Figure 7, where we can see very similar results between countries. Highways and other roads account for 93.4% and 6.6% of the routes tested, respectively. Given that there is not an even representation of highways and roads, we chose to compare acceleration events relative to distance travelled. Here, we have chosen the calculation of the number of acceleration events per 1000 km as a suitable value for a comparison of acceleration events in the longitudinal and lateral direction, as well as for highways \begin{table}
\begin{tabular}{l c c} \hline \hline
**Testing Scenario** & \multicolumn{2}{c}{\(p\)**-Value**} \\ \hline  & **ax1000** & **ay1000** \\ \hline
2 directions (SK-DE and back) & 0.1400 & 0.1057 \\
2 vehicle combinations & 0.9021 & 0.1951 \\
3 countries (SK, AT, DE) & 0.0634 & 0.9713 \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Kruskal–Wallis test results for maximum ax1000 and ay1000 values of acceleration events and different testing scenarios. Figure 7: Box-plots of maximum values of acceleration events of ay1000 for individual countries from Kruskal–Wallis test from Matlab. and other roads (see Tables 8 and 9). Although we anticipated that the relative number of acceleration events on the roads would be higher, we did not anticipate that the difference would be so large. There are 498.8 events/1000 km on roads and 39.1 events/1000 km on highways when considering x-axis acceleration events in the interval between 0.1 g and 0.2 g, and 30.7 events/1000 km on roads, but only 1.4 events/1000 km on highways above 0.2 g. Longitudinal acceleration events higher than 0.3 g occur rarely at 1.5 event/1000 km. There are 649.3 events/1000 km on roads and 31.2 events/1000 km on highways when considering y-axis acceleration events in the interval between 0.1 g and 0.2 g, and 69.7 events/1000 km on roads, but only 3.2 events/1000 km on highways above 0.2 g. Lateral acceleration events higher than 0.3 g occur rarely at 1.5 event/1000 km. The absolute number of acceleration events in the lateral direction is higher than in the longitudinal direction but there are more longitudinal events/1000 km on highways and more lateral events/1000 km on roads. An acceleration of 0.2 g is considered as the minimum stability of the load unit that should withstand transport. A load unit with a stability from 0.2 g to 0.3 g could be considered as the weakest load unit. The test results show that even the weakest load units such as these can be damaged in transports, as semi-trailer vehicle combinations still reach longitudinal ax1000 and lateral ay1000 accelerations between 0.2 g and 0.3 g relatively \begin{table}
\begin{tabular}{c c c c} \hline Total distance [km] & 10,109 & 718 & 10,827 \\ \hline \multicolumn{4}{c}{Acceleration events} & Total \\ ax1000 & Highways & Roads & \\
[0.1; 0.2) & 395 & 358 & 753 \\
[0.2; 0.3) & 13 & 21 & 34 \\
[0.3; 0.4) & & 1 & 1 \\
[0.4; 0.5) & 1 & & 1 \\ \hline Total & 409 & 380 & 789 \\ \hline \multicolumn{4}{c}{Acceleration events per 1000 km} & Total \\ ax1000 & Highways & Roads & \\
[0.1; 0.2) & 39.1 & 498.8 & 537.9 \\
[0.2; 0.3) & 1.3 & 29.3 & 30.5 \\
[0.3; 0.4) & 0.0 & 1.4 & 1.4 \\
[0.4; 0.5) & 0.1 & 0.0 & 0.1 \\ \hline Total & 40.5 & 529.5 & 569.9 \\ \hline \end{tabular}
\end{table} 
Table 8: Acceleration events for highways and roads for ax1000.