## 3 Results and Discussions
### Results of Predicting Age Information for Unlabeled Datasets and Exploration
#### 3.4.2 On the Correlations between Age Groups  
Regarding correlations between age groups, Figure 11 shows the overall correlations between age groups based on the measured \(correlation_{news}\big{(}g_{i},g_{j}\big{)}\) values. Overall, the correlation between 10s and 20s was the largest, whereas 30s and \(\geq\)50s showed the smallest correlation. Considering all age group pairs, the most correlated age group for each age group pair was as follows: 20s similar to 10s, 10s to 20s, 40s to 30s, \(\geq\)50s to 40s, and 40s to \(\geq\)50s. This means that the correlation between close age groups was the largest, which is the same as the previous results of Figure 10, which show that the similarity between close age groups was the highest. Furthermore, Figure 12 shows the correlation within a section measured for each age group pair. From Figure 12, it can be seen that with respect to common topics of interest between age groups, differences in correlation existed between them. The results in all sections are as follows. Overall, (10s, 20s) showed the greatest positive correlations in all sections. Among them, the correlation was the largest in the \"Society\" section. Similarly, all sections showed positive correlations for (20s, 30s), although the correlations were smaller than those for (10s, 20s). Contrastingly, overall, it was shown that (30s, \(\geq\)50s) had the greatest negative correlations across all sections; in particular, in the \"Politics\" section, (30s, \(\geq\)50s) showed the lowest correlation. These findings, based on the \(correlation_{section}\big{(}S,g_{i},g_{j}\big{)}\) values, imply that the age difference in terms of topic correlations is small for (10s, 20s) and (20s, 30s), but large in (30s, \(\geq\)50s). Thus, it is also expected that the above identified small or large topic similarities between age groups could have caused more conflicts and social problems between different age groups. Figure 11: The measured correlations between age groups. *** indicates the significance level of \(p\) < 0.01. In addition, the Tables in Supplementary B show the results when the correlation between age groups was analyzed more carefully by obtaining and using \(correlation_{subsection}\big{(}s,g_{i},g_{j}\big{)}\) values. The results can be condensed as shown in Table 11, by listing the identified top five and bottom five subsections in terms of \(correlation_{subsection}\big{(}s,g_{i},g_{j}\big{)}\) for each age group pair. Table 11 reveals more detailed reasons for the correlations regarding topics of interest between age groups that can be examined and discussed. For example, the correlation between 10s and 20s in the \"Society\" section was the largest of all, as revealed in Figure 12, but when investigated more closely, it was seen in Table 11 that the two age groups had the largest correlation in the \"Real Estate\" subsection, belonging to the \"Economy\" section. Moreover, (30s, \(\geq\)50s) in the \"Political\" section showed the lowest correlation among all age group pairs in Figure 12, and it was found from Table 11 that the detailed subsection in the \"Politics\" section was the \"President's Office\" subsection. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multicolumn{5}{c}{**(a) Top 5 Subsections**} \\ \hline \hline \multicolumn{5}{c}{**Age Group Pairs**} & \multicolumn{2}{c}{**Rank**} \\ \cline{2-6} \multicolumn{1}{c}{(g\({}_{i},g_{j}\))} & **1** & **2** & **3** & **4** & **5** \\ \hline \multicolumn{5}{c}{(10s, 20s)} & Real Estate & Road/Traffic & Food/Medical & The Press & Case/Accident \\ \hline \multirow{3}{*}{(10s, 30s)} & National Assembly/Political Party & President’s Office & North Korea & The Press & Politics General \\ \cline{2-6}  & National Defense/Diplomacy & North Korea & USA/Latin America & World General & Middle East/Africa \\ \hline \multirow{3}{*}{(10s, \(\geq\)50s)} & \multirow{3}{*}{Stock} & \multirow{3}{*}{Car/Test Drive} & Human Rights/Welfare & \multirow{3}{*}{Labor} & \multirow{3}{*}{Fashion/Beauty} \\  & & & & & \\ \end{tabular}
\end{table}