## 4 Results and Discussion
### Measurement Results in Statistical Analysis
\begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline \multicolumn{2}{c}{**Gear**} & \multicolumn{3}{c}{**Drawing Information**} & \multicolumn{6}{c}{**Calculated Errors in 5 to 10 IT Grades according to DIN**} \\  & & & & & & & & 3961 & & & **Qualified for** \\ \hline
**No. ** & **Mark** & \begin{tabular}{c} **IT Grade** \\ **Information** \\ \end{tabular}  & \ \begin{tabular}{c} **According to** \\ **the Standard** \\ \end{tabular}  & \begin{tabular}{c} **Permissible** \\ **Errors [mm]** \\ \end{tabular}  & **5** & **6** & **7** & **8** & **9** & **10** & **17** & **Grade** \\ \hline
1 & 16 & 7 & DIN 3967 & \begin{tabular}{c} \(\Delta M=0.028\) \\ \(\Delta g=0.030\) \\ \(\Delta g=0.005\) \\ \end{tabular}  & 0.010 & 0.014 & 0.020 & 0.027 & 0.038 & 0.054 & \\  & & & & & & \(\Delta g=0.005\) \\ \hline
2 & 13 & – & – & – & \begin{tabular}{c} \(\Delta M=0.022\) \\ \(\Delta g=0.025\) \\ \(\Delta g=7\) \\ \end{tabular}  & 0.013 & 0.018 & 0.025 & 0.034 & 0.048 & 0.067 & \\  & & & & & \(\Delta g=0.037\) & 0.013 & 0.019 & 0.026 & 0.037 & 0.051 & 0.072 & \\
4 & 2 & – & – & – & \begin{tabular}{c} \(\Delta M=0.007\) \\ \(\Delta g=0.007\) \\ \end{tabular}  & 0.007 & 0.010 & 0.013 & 0.019 & 0.026 & 0.042 & \\ \hline
5 & 3 & – & – & – & \begin{tabular}{c} \(\Delta t_{p}=0.010\) \\ \(\Delta g=0.030\) \\ \(\Delta t_{p}=7\) \\ \end{tabular}  & 0.007 & 0.009 & 0.013 & 0.018 & 0.025 & 0.040 & 6 \\ \hline
6 & 5 & 7 & DIN 3962 & \begin{tabular}{c} \(\Delta g=0.030\) \\ \(\Delta t_{p}=7\) \\ \end{tabular}  & 0.008 & 0.012 & 0.016 & 0.023 & 0.032 & 0.045 & \\  & & & & & \(\Delta t_{p}=7\) & 0.004 & 0.006 & 0.009 & 0.012 & 0.017 & 0.027 & \\ \hline
7 & 11 & 9 & DIN & \begin{tabular}{c} \(\Delta M=0.024\) \\ \(\Delta t_{p}=7\) \\ \end{tabular}  & 0.012 & 0.017 & 0.024 & 0.033 & 0.046 & 0.065 & \\  & & & & & \(\Delta t_{p}=7\) & 0.006 & 0.009 & 0.012 & 0.017 & 0.024 & 0.039 & \\ \hline
8 & 6 & 1 & \ \begin{tabular}{c} industry \\ standard \\ \end{tabular}  & \begin{tabular}{c} \(\Delta M=0.054\) \\ \(\Delta g=0.060\) \\ \(\Delta t_{p}=7\) \\ \end{tabular}  & 0.012 & 0.017 & 0.024 & 0.033 & 0.047 & 0.089 & \\  & & & & \(\Delta g=0.060\) & 0.013 & 0.018 & 0.025 & 0.036 & 0.050 & 0.070 & 9 \\  & & & & & \(\Delta t_{p}=7\) & 0.006 & 0.009 & 0.013 & 0.018 & 0.025 & 0.039 & \\ \hline \hline \end{Figure 8: Graphs for Gear No. 3 Mark 2: (**a**) Estimated Tolerance Areas and (**b**) Estimator Ratio for Models I to XI. Figure 10: Graphs for Gear No. 5 Mark 3: (**a**) Estimated Tolerance Areas and (**b**) Estimator Ratio for Models I to XI. Figure 7: Graphs for Gear No. 2 Mark 13: (**a**) Estimated Tolerance Areas and (**b**) Estimator Ratio for Models I to XI. Figure 9: Graphs for Gear No. 4 Mark 2: (**a**) Estimated Tolerance Areas and (**b**) Estimator Ratio for Models I to XI. So, there is one gear in grade 6, two gears in grade 7, three gears in grade 8, and two gears in grade 9. The direction and degree of shift of the graphs relative to the nominal zone were determined. The degree of shift was determined relative to the _Average_ and _Median_ (two parameters that were used as the center of the measurement data distribution). The results are presented in Table 8. Each parameter that better approximates the nominal dimension is marked in green. The following formulas were used:  
\[\delta_{1}=\frac{|NS-Average|}{NS}.1000\ \% \tag{34}\]  
\[\delta_{2}=\frac{|NS-Median|}{NS}.1000\ \% \tag{35}\]  
In the case of Gear No. 7 Mark 11, the _Average_ and _Median_ had the same value. Overall, the _Average_ was three times more effective, while the _Median_ was four times more effective. Due to similar results and a relatively small number of tested wheels, it is not possible to select a better parameter that estimates the nominal value of the basic pitch. The shift to the right occurred five times. The shift to the left occurred three times. In subsequent tests, the nature and potential source of wear of the tested gears should be determined. Except in the case of Gear No. 4 Mark 2 (which, by the way, is the same wheel as Gear No.