# Semantic Search Enhanced with Rating Scores
## 4 SemSim\({}^{e}\) Evaluation
In Table 5 \(SemSim\), \(SemSim_{RV}\), and \(SemSim^{e}\) correlations with \(HJ\) are given. We observe that \(SemSim^{e}\) has higher values in 73% of cases. Table 6 shows the precision and recall for all the users, where \"-\" stands for undefined because the set of retrieved resources is empty. Note that with respect to \(SemSim\) the precision of \(SemSim^{e}\) increases in 5 cases and decreases in 1 case, while the recall increases in most of the cases. Regarding to \(SemSim_{RV}\) the precision of \(SemSim^{e}\) is the same while the recall increases in 4 cases and is the same for the remaining cases. \begin{table}
\begin{tabular}{c c|c c|c c|c c} \hline \hline \multicolumn{2}{c|}{\(HJ\)} & \multicolumn{2}{c|}{\(SemSim\)} & \multicolumn{2}{c|}{\(SemSim_{RV}\)} & \multicolumn{2}{c}{\(SemSim^{e}\)} \\ \hline P1 & 0.95 & P3 & 0.76 & P3 & 0.76 & P3 & 0.61 \\ P3 & 0.8 & P4 & 0.40 & P4 & 0.64 & P4 & 0.50 \\ P4 & 0.5 & P1 & 0.36 & P1 & 0.44 & P1 & 0.42 \\ \hline P5 & 0.4 & P9 & 0.26 & P9 & 0.26 & P5 & 0.23 \\ P8 & 0.2 & P5 & 0.20 & P5 & 0.24 & P9 & 0.22 \\  & & P10 & 0.18 & P10 & 0.22 & P10 & 0.12 \\  & & P7 & 0.07 & P7 & 0.07 & P7 & 0.06 \\  & & P8 & 0.07 & P8 & 0.07 & P8 & 0.05 \\  & & P2 & 0.02 & P2 & 0.02 & P2 & 0.02 \\  & & P6 & 0.00 & P6 & 0.00 & P6 & 0.00 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: User U3. \begin{table}
\begin{tabular}{c|l} \hline \hline _Users_ & **RV\({}^{e}\)** \\ \hline U1 & (InternationalHotel (M), Train (M), ArcheologicalSite (\(H\)), MediterraneanMeal (\(H\))) \\ U2 & (Campsite (\(H\)), BikeRiding (\(M\)), Trekking (\(H\)), MediterraneanMeal (\(M\))) \\ U3 & (InternationalHotel (\(H\)), Flight (\(M\)), LocalTransportation (\(H\)), InternationalMeal (\(H\)), \\  & Attraction (\(H\))) \\ U4 & (Bed\&Breakfast (\(M\)), Flight (\(H\)), Museum (\(M\)), EthnicMeal (\(L\))) \\ U5 & (Bed\&Breakfast (\(M\)), Riding (\(H\)), Boating (\(M\)), VegetarianMeal (\(H\)), Shopping (\(L\))) \\ U6 & (InternationalHotel (\(M\)), Flight (\(M\)), Trekking (\(H\)), MediterraneanMeal (\(H\)), \\  & ShoppingCenter (\(L\)) \\ U7 & (InternationalHotel (\(H\)), LocalTransportation (\(M\)), CulturalActivity (\(H\)), \\  & Entertainment (\(L\)), Flight (\(H\))) \\ U8 & (Farmhouse (\(H\)), Train (\(H\)), Boating (\(H\), MediterraneanMeal (\(M\))) \\ U9 & (Bed\&Breakfast (\(H\)), Train (\(H\)), LocalTransportation (\(H\)), OpenAirActivity (\(M\)), \\  & EthnicMeal (\(M\)), RockConcert (\(M\))) \\ U10 & (Bed\&Breakfast (\(H\)), Museum (\(M\)), MediterraneanMeal (\(H\)), Bazaar (\(H\))) \\ U11 & (Bed\&Breakfast (\(M\)), Car Rental (\(H\)), ArcheologicalSite (\(H\)), \\  & MediterraneanMeal (\(H\)), ShoppingCenter (\(M\)) \\ U12 & (InternationalHotel (\(L\)), Flight (\(M\)), ArcheologicalSite (\(H\)), EthnicMeal (\(M\))) \\ U13 & (Campsite(\(H\)), Train (\(L\)), Trekking (\(M\)), RockConcert (\(M\)), Food (\(L\)) \\ U14 & (InternationalHotel(\(M\)), Flight(\(H\)), LocalTransportation(\(H\)), EthnicMeal(\(M\)), \\  & OpenAirActivity(\(H\))) \\ U15 & (Bed\&Breakfast(\(H\)), OpenAirActivity(\(M\)), EthnicMeal(\(M\)), Bazaar(\(M\)), \\  & Entertainment(\(M\))) \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Request vectors. Note that, due to the presence of the rating scores, the similarity values computed according to \(SemSim^{e}\) never increase with respect to \(SemSim\) and \(SemSim_{RV}\). For this reason, the evaluation of the precision and the recall has been performed on the basis of two different thresholds: 0.5 with regard to \(H\)], \(SemSim\), and \(SemSim_{RV}\), as indicated in Table 4, and 0.4 concerning \(SemSim^{e}\). This distinction allows us to balance the decrease of the similarity values obtained by \(SemSim^{e}\) due to the presence of rating scores. In particular, considering \(U3\) in Table 4, the precision remains invariant (i.e., 1), while the recall increases (0.33 vs. 0.66 vs. 1.00).