# Exploring and Visualizing Research Progress and Emerging Trends of Event Prediction: A Survey
## 4 Results and Discussion
### Document Co-Citation Network Analysis
The potential reason is that this milestone paper was frequently cited for analyzing and forecasting the meteorological events during 2019 and 2020. Another strongly cited document in the most recent years (i.e., from 2019 to 2022) is a review paper surveying the rainfall thresholds for landslide occurrence since threshold selection is usually a big concern among scholars and this paper provides highly persuasive reference. The other documents with strong citation bursts mainly aim at proposing specific equations and models for predicting meteorological events and natural hazards. Their citation bursts last for two or three years during 2015 and 2019, indicating during those periods, those equations and models had gained widespread recognition and acceptance within the academic community. To identify distinct groups of documents with high homogeneity, we performed cluster analysis on the document co-citation network. Figure 8 illustrates the network divided into five clusters, each represented by a different color. The modularity, indicated by a \begin{table}
\begin{tabular}{l c c c c c c} \hline \hline
**Title** & **Betweenness** & **Degree** & **Closeness** & **Author** & **Year** & **Source** \\ \hline Calibration and validation of rainfall thresholds for shallow landslide forecasting in Sicily, Southern Italy & 0.45 & 22 & 0.64 & \begin{tabular}{c} [PERSON] \\ et al. \\ \end{tabular} & 2015 & Geomorphology \\ \hline Objective definition of rainfall intensity-duration thresholds for the initiation of post-fire debris flows in Southern California & 0.44 & 20 & 0.65 & \begin{tabular}{c} [PERSON] \\ et al. \\ \end{tabular} & 2013 & Landslides \\ \hline Deep learning for short-term traffic flow prediction & 0.44 & 16 & 0.67 & \begin{tabular}{c} [PERSON], \\ and \\ [PERSON] \\ \end{tabular} & 2017 & \begin{tabular}{c} Transportation \\ Research Part C: \\ Emerging \\ Technologies \\ \end{tabular} \\ \hline Review on event detection techniques in social multimedia & 0.40 & 13 & 0.61 & \begin{tabular}{c} [PERSON], and \\ [PERSON] \\ \end{tabular} & 2016 & \
\begin{tabular}{c} Online Information \\ Review \\ \end{tabular} \\ \hline Ontology-based deep learning for human behavior prediction with explanations in health social networks & 0.39 & 16 & 0.63 & [PERSON] et al. & 2017 &
\begin{tabular}{c} Information \\ Sciences \\ \end{tabular} \\ \hline \hline \end{tabular}
\end{table} 
Table 7: The top five documents sorted by betweenness centrality. \begin{table}
\begin{tabular}{l c c c c} \hline \hline
**Title** & **Citation Burst** & **Author** & **Burst Year (Begin to End)** & **Source** \\ \hline The JRA-55 reanalysis: general specifications and basic characteristics & 8.03 & \begin{tabular}{c} [PERSON] \\ et al. \\ \end{tabular} & 2019–2020 & \begin{tabular}{c} Journal of the \\ Meteorological Society \\ of Japan \\ \end{tabular} \\ \hline A review of the recent literature on rainfall thresholds for landslide occurrence & 7.66 & \begin{tabular}{c} [PERSON] \\ et al. \\ \end{tabular} & 2019–2022 & Landslides \\ \hline NGA-West2 equations for predicting PGA, FGV, and 5\% damped PSA for shallow crustal earthquakes & 7.58 & \begin{tabular}{c} [PERSON] \\ et al. \\ \end{tabular} & 2016-2019 & Earthquake Spectra \\ \hline Empirical ground-motion models for point- and extended-source crustal earthquake scenarios in Europe and the Middle East & 6.86 & \begin{tabular}{c} [PERSON] \\ et al. \\ \end{tabular} & 2017–2019 & \begin{tabular}{c} Bulletin of Earthquake \\ Engineering \\ \end{tabular} \\ \hline Skill of real-time seasonal ENSO model predictions during 2002–2011: Is our capability increasing & 6.26 & \
\begin{tabular}{c} [PERSON] \\ et al. \\ \end{tabular} & 2015–2017 &
\begin{tabular}{c} Bulletin of the American \\ Meteorological Society \\ \end{tabular} \\ \hline \hline \end{tabular}
\end{table} 
Table 8: The top five documents sorted by the citation burst. Q value of 0.8537, and the weighted S value of 0.932 both fall within desirable ranges.