## 5 Expertise Retrieval
### Measuring Similarity Between Mobile Apps' Descriptions
#### 5.1.2 App Description Similarity Setup
A scatter plot visualization of the similarity scores using SBERT for all mobile apps' descriptions in our dataset, not only 15 descriptions, is shown in Figure 7a-f. Each graph shows the similarity between one of the six defined queries previously discussed and all mobile apps' descriptions in the dataset belonging to a certain domain or all domains depending on the query design. The figures demonstrate the distribution of the crowd--mobile apps' users and/or developers--by the similarity of the mobile apps they have used or developed. Figure 5: Correlation coefficient between human judgments and cosine similarity produced by SBERT and Doc2 Vec for 15 pairs of apps’ descriptions for six query descriptions. \begin{table}
\begin{tabular}{c c c c c} \hline  & \multicolumn{2}{c}{\(\mathbf{q_{2}}\)} \\ \cline{2-5}  & **App Name** & **SBERT** & **Doc2 Vec** & **H.J.** \\ \hline D1 & English Crossword puzzle & 0.68 & 0.70 & 6.25 \\ \hline D2 & English Crosswords Puzzle Game & 0.68 & 0.65 & 7.08 \\ \hline D3 & Crossword Puzzle Universe & 0.62 & 0.47 & 6.83 \\ \hline D4 & Cross Search Word Puzzles & 0.62 & 0.75 & 5.73 \\ \hline D5 & Puzzle Page—Daily Puzzles & 0.51 & 0.49 & 4.58 \\ \hline D6 & Jigsaw Puzzles—Block Puzzle & 0.31 & 0.56 & 2.67 \\ \hline D7 & Moncage & 0.31 & 0.51 & 3.5 \\ \hline D8 & Cubi Code—Logic Puzzles & 0.30 & 0.45 & 5.5 \\ \hline D9 & Neon Blocks & 0.30 & 0.61 & 3.83 \\ \hline D10 & Swiped Words & 0.40 & 0.54 & 5.17 \\ \hline D11 & Cooking Dary Restaurant Game & 0.15 & 0.45 & 0 \\ \hline D12 & Monster Survival & 0 & 0.60 & 0 \\ \hline D13 & Goblin’s Workshop & 0.01 & 0.43 & 0 \\ \hline D14 & Bouncy Hoops & 0.02 & 0.41 & 0 \\ \hline D15 & Mars: Mars & \(-\)0.01 & 0.33 & 0 \\ \hline C.C. & Correlation Coefficient with H.J. & 0.942 & 0.563 & - \\ \hline \end{tabular}
\end{table} 
Table 4: SBERT, Doc2 Vec and H.J. similarity scores between app descriptions and query 2 description. Figure 6: Correlation coefficient results for pre-trained SBERT and Doc2 Vec. \begin{table}
\begin{tabular}{c c c c c} \hline  & \multicolumn{2}{c}{\(\mathbf{q_{1}}\)} \\ \cline{2-5}  & **App Name** & **SBERT** & **Doc2 Vec** & **H.J.** \\ \hline D1 & GymBook Strength Training & 0.77 & 0.41 & 7.12 \\ \hline D2 & Weatherthals & 0.76 & 0.44 & 6.75 \\ \hline D3 & JEFIT Workout Planner Gym Log & 0.74 & 0.50 & 7.42 \\ \hline D4 & Pacer Pedometer \& Step Tracker & 0.73 & 0.46 & 7.5 \\ \hline D5 & Impact—Steps Fitness Charity & 0.71 & 0.50 & 6 \\ \hline D6 & Health CSV Importer & 0.49 & 0.38 & 4.5 \\ \hline D7 & HeartsApp: Trainer Resource & 0.49 & 0.49 & 4 \\ \hline D8 & Zero: Fasting \& Health Tracker & 0.49 & 0.46 & 5.08 \\ \hline D9 & Intermittent Fasting GoFasting & 0.49 & 0.48 & 4.83 \\ \hline D10 & Gain Weight App: Diet Exercise & 0.48 & 0.51 & 4.58 \\ \hline D11 & European Air Quality Index & 0.09 & 0.49 & 0.25 \\ \hline D12 & Australian Bitles and Stings & 0.04 & 0.27 & 0.17 \\ \hline D13 & Pranayama Free & 0.35 & 0.39 & 0.33 \\ \hline D14 & Disney Magic Timer by Oral-B & 0.11 & 0.43 & 0.42 \\ \hline D15 & Ciprea & 0.12 & 0.23 & 0 \\ \hline C.C. & Correlation Coefficient with H.J. & 0.960 & 0.551 & - \\ \hline \end{tabular}
\end{table} 
Table 3: SBERT, Doc2 Vec and H.J. similarity scores between app descriptions and query 1 description.