# Road Infrastructure Investment Limits Based on Minimal Accidents Using Artificial Neural Network
## 2 Data and Methodology
### Description and Basic Statistics of Data  
The basic statistics of the variables, including the average, standard deviation, median, maximum, and minimum, are presented in Table 1. A detailed description of the dataset is given in the following paragraphs. Rows with missing data were excluded from the analysis, leaving about 435 rows. Annual Road Accidents (ARAs) (30): The ARAs are defined as the number of annual road accidents involving a road motor vehicle (excluding suicide using a road motor \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline
**Statistics** & **Mean** & \begin{tabular}{c} **Standard** \\ **Deviation** \\ \end{tabular} & **Median** & **Maximum** & **Minimum** & \begin{tabular}{c} **25 th** \\ **Percentage** \\ \end{tabular} & \
\begin{tabular}{c} **50 th** \\ **Percentage** \\ \end{tabular} &
\begin{tabular}{c} **75 th** \\ **Percentage** \\ \end{tabular} \\ \hline Total Accidents/yr. (1000) & 202 & 449 & 41 & 2275 & 1 & 9 & 41 & 157 \\ \hline Freight (million ton-km) & 269,976 & 776,473 & 37,199 & 4,018,805 & 1864 & 17,344 & 37,199 & 156,986 \\ \hline Passenger (million passenger-km) & 543,779 & 1,162,300 & 124,355 & 5,846,312 & 2143 & 67,088 & 124,355 & 680,863 \\ \hline Change in Number of New Vehicles Registered (\%) & 2.45 & 18.97 & 1.29 & 152.44 & \(-\)72.94 & \(-\)4.82 & 1.29 & 7.47 \\ \hline Existing Road Maintenance Investment \({}^{\ast}\)ERMI (EUR/yr) & 3,509,432,464 & 6,486,214,266 & 755,494,568 & 35,926,399,759 & 16,694,491 & 204,500,000 & 755,494,568 & 3,085,019,372 \\ \hline New Road Infrastructure Investment \({}^{\ast}\)NRMI (EUR/yr) & 8,118,209,606 & 16,109,624,922 & 1,893,299,904 & 79,312,039,934 & 46,000,000 & 653,000,000 & 1,893,299,904 & 6,034,830,090 \\ \hline ERMI Per capita (EUR/yr./Capita) & 84 & 71 & 73 & 387 & 0 & 29 & 73 & 117 \\ \hline NRII Per capita (EUR/yr./Capita) & 163 & 126 & 128 & 757 & 11 & 85 & 128 & 205 \\ \hline Population (Million) & 44.30 & 68.62 & 10.55 & 318.86 & 1.32 & 5.40 & 10.55 & 58.81 \\ \hline Proportion of Work Group (\%) & 67.12 & 2.13 & 66.81 & 73.10 & 62.41 & 65.60 & 66.81 & 68.07 \\ \hline Population of Work Group (Million) & 29.60 & 45.72 & 7.03 & 211.55 & 0.87 & 3.63 & 7.03 & 38.65 \\ \hline Gross Domestic Product (USD/Capita) & 30,005 & 10,974 & 28,707 & 67,051 & 8608 & 22,784 & 28,707 & 36,519 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Basic statistics of data. vehicle) recorded that might have resulted in death (s), injury, and or loss of property. Road motor vehicles include buses, tramways or streetcars, coaches, trolleys, and road vehicles used to transport goods and passengers. Freight Transport [31]: This is defined as the total movement of goods using road transport on a given network expressed in million ton-km. Passenger Transport [32] is defined as the total movement of passengers using road transport on a given network expressed in million passenger-km. Change in Amount of New Vehicle Registrations (CNRV) [33] is defined as the annual increase or decrease in the amount of newly registered vehicles (private and commercial) expressed as a percentage. Existing Road Maintenance Investment (ERMI) [34]: This is defined as the total annual monetary spending towards the preservation of the existing road infrastructure expressed in EUR (EUR). New Road Infrastructure Investment (NRII) [35]: This covers the total annual monetary spending on new road construction to improve the existing road network expressed in EUR (EUR). Population [36] is defined as all nationals present in, or temporarily absent from, a country, and aliens who have permanently settled in a country, and is expressed in millions. The proportion of Working Group [37] is the percentage of the population between 15 and 64 years of age who are employed. The Population of Work Group was estimated from the total population and the proportion of work group and is represented in millions. The Proportion of Work Group is the percentage of the working population with respect to the total population.