# Women's Singles Tennis Match Analysis and Probability of Winning a Point
## 3 Results
### Analysis of Factors Affecting Performance in Women's Singles Tennis in Grand Slam Tournaments
\begin{table}
\begin{tabular}{l l l l l l l l} \hline \hline
**Variables** & \multicolumn{1}{c}{**Clay**} & \multicolumn{1}{c}{**Grass**} & \multicolumn{1}{c}{**Hard**} & \multicolumn{1}{c}{**x2 Inter-Criteria**} \\ \hline  & & \(n\) & \% & \(n\) & \% & \(n\) & \% & \\ \hline  & BSO & 227 & 17.6 & 161 & 17.0 & 168 & 16.7 & \(\chi\)2 = 27,780 \\  & LTO & 174 & 13.5 & 100 & 10.6 & 135 & 13.4 & \(p=0.015\) \\  & NET & 286 & 22.2 & 235 & 24.9 & 243 & 24.1 & \\  & Z1 & 229 & 17.8 & 189 & 20.0 & 175 & 17.4 & \\  & Z2 & 124 & 9.6 & 106 & 11.2 & 112 & 11.1 & \\  & Z3 & 20 & 1.6 & 33 & 3.5 & 27 & 2.7 & \\  & Z4 & 107 & 8.3 & 54 & 5.7 & 73 & 7.3 & \\  & Z5 & 119 & 9.2 & 69 & 7.3 & 73 & 7.3 & \\ \hline  & RW & 564 & 43.9 & 358 & 37.8 & 395 & 39.3 & \(\chi\)2 = 9462 \\  & SW & 722 & 56.1 & 589 & 62.2 & 611 & 60.7 & \(p=0.009\) \\ \hline  & RWFE & 68 & 5.3 & 52 & 5.5 & 49 & 4.9 & \(\chi\)2 = 15,414 \\  & RWUE & 338 & 26.3 & 218 & 23.0 & 255 & 25.3 & \(p=0.118\) \\ Point ending & RWW & 158 & 12.3 & 88 & 9.3 & 91 & 9.0 & \\  & SWFE & 87 & 6.8 & 60 & 6.3 & 73 & 7.2 & \\  & SWUE & 378 & 29.4 & 309 & 32.6 & 316 & 31.4 & \\  & SWW & 257 & 20.0 & 220 & 23.2 & 222 & 22.0 & \\ \hline  & RDF & 59 & 4.6 & 51 & 5.4 & 56 & 5.6 & \(\chi\)2 = 68,373 \\  & RFEBH & 35 & 2.7 & 22 & 2.3 & 22 & 2.2 & \(p=0.002\) \\  & RFEFH & 33 & 2.6 & 28 & 3.0 & 27 & 2.7 & \\  & RFEOT & 0 & 2 & 0.2 & 0 & 0 & \\  & RUEBH & 121 & 9.4 & 70 & 7.4 & 101 & 10.0 & \\  & RUEFH & 154 & 12.0 & 96 & 10.1 & 97 & 9.6 & \\  & RUEOT & 5 & 0.4 & 2 & 0.2 & 1 & 0.1 & \\  & RWBH & 57 & 4.4 & 21 & 2.2 & 38 & 3.8 & \\  & RWFH & 90 & 7.0 & 59 & 6.2 & 49 & 4.9 & \\  & RWOT & 11 & 0.9 & 7 & 0.7 & 4 & 0.4 & \\  & SACE & 46 & 3.6 & 80 & 8.4 & 66 & 6.6 & \\  & SFEBH & 42 & 3.3 & 22 & 2.3 & 36 & 3.6 & \\  & SFEFH & 46 & 3.6 & 36 & 3.8 & 37 & 3.7 & \\  & SFEOT & 0 & 0 & 2 & 0.2 & 0 & 0 \\  & SUEBH & 175 & 13.6 & 140 & 14.8 & 145 & 14.4 & \\  & SUEFH & 200 & 15.6 & 169 & 17.9 & 171 & 17.0 & \\  & SUEOT & 1 & 0.1 & 0 & 0 & 12 & 0.9 & \\  & SWBH & 74 & 5.6 & 41 & 4.3 & 28 & 2.0 & \\  & SWFH & 123 & 9.6 & 86 & 9.1 & 89 & 6.4 & \\  & SWOT & 14 & 1.1 & 13 & 1.4 & 59 & 4.3 & \\ \hline \hline \end{tabular} Note. Abbreviations in Table 1.  
\end{table} 
Table 2: _Cont._respectively). However, the surface on which the most unforced errors were made when serving was grass (32.6%), while in returning the most unforced errors were made on clay (26.3%). Both on serve and return, there were more forehand winners than backhand winners. There were also more unforced errors with the forehand than with the backhand. Statistically significant differences (\(p<0.05\)) were observed between the categories of each of the criteria studied and on each of the three surfaces according to the results of the intra-criteria \(\chi 2\) test (for further details, see Table S1 in the Supplementary Materials). In the comparison between surfaces (inter-criteria \(\chi 2\) test), statistically significant differences were detected in the bounce zone (a higher percentage of points resolved from the serve zone on the two fast surfaces compared to clay, and a higher percentage of points resolved after bouncing in zone 1 and zone 2 on clay compared to the other two), finish zone (among other things, a higher percentage of points finished in zone 4 and zone 5 on clay compared to the other two surfaces, and a lower percentage of points finished on zone 1 and zone 2 on clay compared to grass), point winner (a lower percentage of points won serving on clay compared to the other two surfaces), and final stroke variables. There were no statistically significant differences in the service, rally length, or point ending variables.