## 3 Results
### Results of Statistical Analysis for the NiTi-2 Alloy
Table 15 summarises the results of this testing procedure in the case of the NiTi-1 alloy. The Steel-Dwass-Critchlow-Figner testing procedure confirmed the assumption from Section 3. that the NiTi-1 alloy behaved statistically very similarly in the air and tide environment, and that there was no significant difference between these two datasets, while in the sea environment the corrosion processes deviated from the values created under the influence of air and tide. Different results were found based on the application of the Steel-Dwass-Critchlow-Figner test procedure to the NiTi-2 empirical data relating to the three seawater environments. These results are presented in Table 16.  
Based on the Steel-Dwass-Critchlow-Figner test it can be concluded that all three datasets related to the NiTi-2 corrosion rates in air, tide and sea environments, are significantly different. This means that there is not enough evidence that the NiTi-2 alloy behaves similarly in some of the three observed seawater environments. \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline  & \multicolumn{2}{c}{\(W_{ij}\)} & \multicolumn{2}{c}{\(p\)**-Value**} & \multicolumn{3}{c}{**Significant Differences**} \\ \hline  & **Air** & **Tide** & **Sea** & **Air** & **Tide** & **Sea** & **Air** & **Tide** & **Sea** \\ \hline air & & 0.414 & \(-\)13.284 & & 0.954 & \(<\)0.0001 & & No & Yes \\ \hline tide & \(-\)0.414 & & \(-\)13.645 & 0.954 & & \(<\)0.0001 & No & & Yes \\ \hline sea & 13.284 & 13.645 & & \(<\)0.0001 & \(<\)0.0001 & & Yes & Yes & \\ \hline \hline \end{tabular}
\end{table} 
Table 15: Two-tailed Steel-Dwass-Critchlow-Figner test details for the NiTi-1 alloy. It is well known that a two-tailed KS test can be performed to compare two empirical distributions (Kosos and Kos, 2018). Thus, a comparative pairwise analysis of the behaviour of the alloy influenced by the specified seawater environment was performed using the KS test. Namely, the idea was to gain insight into the similarities or differences in the behaviour of different NiTi alloys in each observed seawater environment. Therefore, three KS tests were performed: The first KS test compared the empirical CDF of alloy NiTi-1 and empirical CDF of alloy NiTi-2 in the air environment; the second test compared the empirical CDF of alloy NiTi-1 and empirical CDF of alloy NiTi-2 in the tidal environment, and, finally, the empirical CDF of the NiTi-1 alloy and empirical CDF of the NiTi-2 alloy in the sea environment were compared in the third KS test. If the empirical CDFs for the two observed samples are denoted by F1 and F2, then the hypothesis of the two-tailed Kolmogorov-Smirnov tests are defined by:  
**H0.**\(F_{1}(x)=F_{2}(x)\). **Ha. **\(F_{1}(x)\
eq F_{2}(x)\). In these tests, test statistics denoted as D were calculated as the maximum absolute difference between the two empirical distributions. Appropriate \(p\)-values were determined, and they were compared with the chosen significance level \(\alpha=0.05\). Test results for all three seawater environments are summarised in Table 17.  
The computed \(p\)-values for air and tide environments were lower than the significance level \(\alpha=0.05\), so the null hypothesis H0 cannot be accepted. This means that the empirical distributions of the two NiTi samples are statistically significantly different regarding the corrosion rate in both air and tide environments. The risk to reject the null hypothesis H0, while it is true, was lower than 2.9% when the air environment was observed, while it was lower than 0.01% when the tide environment was observed. It can be noted that the computed \(p\)-value was greater than the significance level \(\alpha=0.05\) when the sea environment was observed. Thus, null hypothesis H0 cannot be rejected in the case of sea influence on NiTi-1 and NiTi-2 alloys. This indicates that there is not enough evidence that, statistically, these two alloys were behaving differently in the sea environment. The risk to reject the null hypothesis H0, while it is true, is 18.9%.