# Improving Human Activity Monitoring by Imputation of Missing Sensory Data: Experimental Study
## 3 Results
### Data Classification  
#### 3.2.1 Non-Normalized Data  
Considering the accelerometer data, the results obtained with non-imputed and non-normalized data are reported in the confusion matrix presented in Table 6. The implemented method reported an accuracy of 22.9%, a precision of 19.65%, a recall value of 22.9%, and an F1 score of 21.15%. Considering the accelerometer and magnetometer sensors' data, the results obtained with non-imputed and non-normalized data are reported in the confusion matrix presented in Table 7. The implemented method reported an accuracy of 40.69%, a precision of 56.4%, a recall value of 40.69%, and an F1 score of 47.27%. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & \multicolumn{5}{c}{**Predicted Class**} \\ \hline  & \begin{tabular}{c} **Walking** \\ **Downstairs** \\ \end{tabular} & \begin{tabular}{c} **Walking** \\ **Upstairs** \\ \end{tabular} & \begin{tabular}{c} **Running** \\ **Ustairs** \\ \end{tabular} & \
\begin{tabular}{c} **Standing** \\ **Ustairs** \\ \end{tabular} &
\begin{tabular}{c} **Walking** \\ **Ustairs** \\ \end{tabular} \\ \hline \multirow{5}{*}{Actual Class} & Walking Downstairs & 290 & 0 & 0 & 1709 & 1 \\ \cline{2-6}  & Walking Upstairs & 210 & 0 & 0 & 1790 & 0 \\ \cline{1-1} \cline{2-6}  & Running & 3 & 1 & 0 & 1996 & 0 \\ \cline{1-1} \cline{2-6}  & Standing & 0 & 0 & 0 & 2000 & 0 \\ \cline{1-1} \cline{2-6}  & Walking & 1 & 0 & 0 & 1999 & 0 \\ \hline \hline \end{tabular}
\end{table} 
Table 6: Confusion matrix related to non-normalized and non-imputed data from the accelerometer sensor. Figure 4: Imputed data for the accelerometer sample related to moving downstairs. Considering the accelerometer, magnetometer, and gyroscope sensors' data, the results obtained with non-imputed and non-normalized data are reported in the confusion matrix presented in Table 8. The implemented method reported an accuracy of 74.46%, a precision of 78.24%, a recall value of 74.46%, and an F1 score of 76.3%. Considering the accelerometer data, the results obtained with imputed and non-normalized data are reported in the confusion matrix presented in Table 9. The implemented method reported an accuracy of 20%, a precision of 20%, a recall value of 20%, and an F1 score of 20%. Considering the accelerometer and magnetometer sensors' data, the results obtained with imputed and non-normalized data are reported in the confusion matrix presented in Table 10. The implemented method reported an accuracy of 20.1%, a precision of 73.34%, a recall value of 20.1%, and an F1 score of 31.55%. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline  & \multicolumn{6}{c}{**Predicted Class**} \\ \hline  & \multicolumn{2}{c}{**Walking Downstairs**} & \multicolumn{2}{c}{**Walking Upstairs**} & \multicolumn{2}{c}{**Running**} & \multicolumn{2}{c}{**Standing**} & \multicolumn{2}{c}{**Walking**} \\ \hline  & Walking Downstairs & 179 & 2 & 20 & 1791 & 8 \\ \cline{2-6} \multirow{3}{*}{Actual Class} & Walking Upstairs & 67 & 13 & 8 & 1912 & 0 \\ \cline{2-6}  & Running & 1 & 0 & 1877 & 121 & 1 \\ \cline{2-6}  & Standing & 0 & 0 & 0 & 2000 & 0 \\ \cline{2-6}  & Walking & 4 & 0 & 2 & 1994 & 0 \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Confusion matrix related to non-normalized and non-imputed data from the accelerometer and magnetometer sensors. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline  & \multicolumn{6}{c}{**Predicted Class**} \\ \hline  & \multicolumn{2}{c}{**Walking Downstairs**} & \multicolumn{2}{c}{**Walking Upstairs**} & \multicolumn{2}{c}{**Running**} & \multicolumn{2}{c}{**Standing**} & \multicolumn{2}{c}{**Walking**} \\ \hline  & Walking Downstairs & 99 & 1534 & 2 & 5 & 360 \\ \cline{2-6}  & Walking Upstairs & 31 & 1618 & 0 & 7 & 344 \\ \cline{2-6}  & Running & 0 & 38 & 1879 & 29 & 54 \\ \cline{2-6}  & Standing & 0 & 14 & 0 & 1986 & 0 \\ \cline{2-6}  & Walking & 1 & 80 & 0 & 55 & 1864 \\ \hline \hline \end{tabular}
\end{table} 
Table 8: Confusion matrix related to non-normalized and non-imputed data from the accelerometer, magnetometer, and gyroscope sensors.