# Effective Bus Travel Time Prediction System of Multiple Routes: Introducing PMLNet Based on MDARNN
## 3 Materials and Methods
### Method
#### 3.2.2 Traffic Impact Factors  
To improve prediction accuracy, the impact of real-time traffic should also be considered [22]. Inspired by [3] traffic factors definition and real-time traffic impacts can be expressed in terms of multiple buses traveling and dwelling or passenger transfer status at the bus stop at the most recent period of time. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Travel Chain** & **Sub-Dataset** & **Start** & **End** & **Transfer** \\ \hline
805 to 248 & \(D_{805-248}\) & Jialing Garden & Xianfeng Street & Shuangbei \\
202 to 121 & \(D_{202-121}\) & Shapingba Station & South of TJZ & Golden Fort \\
805 to 202 & \(D_{805-202}\) & Jialing Garden & Golden Fort & Shapingba Station \\
121 to 202 & \(D_{121-202}\) & SM Square & Rongjing City & Golden Fort \\ \hline \hline \end{tabular}
\end{table} 
Table 4: The corresponding information for each travel chain. Based on this, corresponding to \(t_{CDSTT}\), \(t_{SSTT}\), \(t_{BSDT}\), and \(t_{TPWT}\), 4 traffic impact factors, \(\alpha_{CDSTT}\), \(\alpha_{SSTT}\), \(\alpha_{BSDT}\), and \(\alpha_{TPWT}\), are defined as Equation (9), while the Table 5 lists the corresponding explanations of variables. \(\alpha_{CDSTT}\) quantifies the impact of real-time traffic conditions on the travel time of the current driving segment. In contrast, \(\alpha_{BSDT}\) characterizes the influence of real-time traffic conditions on bus stay time at stops. Meanwhile, \(\alpha_{SSTT}\) represents the effect of real-time traffic conditions on the inter-stop travel time between stop \(k\) and stop \(k+1\). Finally, \(\alpha_{TPWT}\) reflects the impact of real-time traffic conditions on passenger waiting time at transfer points. \[\left\{ \begin{aligned} \alpha_{CDSTT}&=1+\frac{1}{n} \sum_{q=1}^{n}\frac{\overline{t_{CDSTT}^{q}}-t_{CDSTT}^{q}}{t_{CDSTT}^{q}}\\ \alpha_{SSTT(k+1)}&=1+\frac{1}{u}\sum_{q=1}^{u} \frac{\overline{t_{SSTT(k+1)}^{q}}-t_{SSTT(k+1)}^{q}}{t_{SSTT(k,k+1)}^{q}} \\ \alpha_{BSDT(k)}&=1+\frac{1}{v}\sum_{q=1}^{v} \frac{\overline{t_{BSDT(k)}^{q}}-t_{BSDT(k)}^{q}}{t_{BSDT(k)}^{q}}\\ \alpha_{TPWT}&=1+\frac{1}{w}\sum_{q=1}^{w}\frac{ \overline{t_{TPWT}^{q}}-t_{TPWT}^{q}}{t_{TPWT}^{q}}\end{aligned} \right. \tag{9}\] \begin{table}
\begin{tabular}{l l} \hline \hline
**Variable/Function** & **Explanation** \\ \hline \(\alpha_{CDSTT}\) & The Current Driving Segment Travel Time factor. \\ \(t_{CSDTT}^{q}\) & The predicted Current Driving Segment Travel Time of bus \(q\). \\ \(t_{CDSTT}^{q}\) & The real Current Driving Segment Travel Time of bus \(q\). \\ \(n^{c}\) & The number of buses passed through CDS during time period \([t_{0}-30\min,t_{0}]\), \(q\in n\), \(t_{0}\) is the current time. \\ \(\alpha_{SSTT(k,k+1)}\) & The stop-stop travel factor of the segment between \(Stop_{k}\) and \(Stop_{k+1}\). \\ \(u^{c}\) & The number of buses passed through the segment between \(Stop_{k}\) and \(Stop_{k+1}\) during time period \([t_{0}-30\min,t_{0}]\), \(q\in u\). \\ \(t_{SST(k,k+1)}^{q}\) & The predicted Stop-to-Stop Travel Time of bus \(q\) through the segment between \(Stop_{k}\) and \(Stop_{k+1}\). \\ \(t_{SST(k,k+1)}^{q}\) & The real Stop-to-Stop Travel Time of bus \(q\) through the segment between \(Stop_{k}\) and \(Stop_{k+1}\). \\ \(\alpha_{BSDT(k)}\) & The bus stopwelling factor of \(Stop_{k}\). \\ \(\upsilon^{c}\) & The number of buses dwelled at \(Stop_{k}\), during time period \([t_{0}-30\min,t_{0}]\), \(q\in v\). \\ \(t_{BSDT(k)}^{q}\) & The predicted Bus Stop Dwelling Time of bus \(q\) at \(Stop_{k}\). \\ \(t_{BSDT(k)}^{q}\) & The real Bus Stop Dwelling Time of bus \(q\) at \(Stop_{k}\). \\ \(\alpha_{TPWT}\) & The Transfer Point Waiting Time factor. \\ \(t_{TPWT}^{q}\) & The predicted waiting time for the \(q\)th same transfer at the transfer point. \\ \(t_{TPWT}^{q}\) & The real waiting time for the \(q\)th same transfer at the transfer point. \\ \(w^{c}\) & The number of transfer times at transfer point during time period \([t_{0}-30\min,t_{0}]\), \(q\in w\). \\ \hline \hline \end{tabular}
\end{table}