Here are three questions this dataset can answer well. The surface figures come from the `raw_kaggle_by_Surface` gold table I queried. ## 1. How much does surface change a player's serve, and is that just a ranking effect? Average aces per player-match differ a lot by surface: | Surface | Avg aces | Avg double faults | |---|---|---| | Carpet | ~7.9 | ~3.1 | | Grass | ~7.6 | ~3.2 | | Hard | ~5.9 | ~3.0 | | Clay | ~3.4 | ~2.8 | Double faults barely move, so the surface effect is mostly about aces. The catch is that the players are not the same on each surface. Average player rank (`Rk`, where lower is better) is about 151 on grass, 311 on hard, 361 on clay and 517 on carpet. Grass has only 9,479 rows against 117,571 for hard and 107,650 for clay. The obvious follow-up is to compare the same players across surfaces, or control for `Rk` and `vRk`. That would show how much of the ace gap is the surface and how much is who plays there. The gold tables `raw_kaggle_by_Surface_Rd` and `return_kaggle_by_Surface_Rk` support this. ## 2. How do serve and return profiles change against stronger or weaker opponents? Every match row carries the player's rank (`Rk`) and the opponent's rank (`vRk`). The serve table has first- and second-serve points won and break points saved (`Bpsvd`). The return table has return points won (`RPW`) and break-point conversion (`BPCnv`). You could bucket opponents by `vRk` and see where a player's edge disappears: is it first-serve dominance, second-serve vulnerability, or return pressure? This is the core input for scouting and pre-match win-probability models. The gold tables `return_kaggle_by_Rk_against`, `return_kaggle_by_Rd_Rk` and `serve_kaggle_by_Bpsvd` are already aggregated along these lines. ## 3. Does performance change by round, by tournament, or over time? Round (`Rd`, about 14 values) and tournament (about 3,963 distinct values) are both available. The players-by-year table (`raw.players_tournament_man_`) covers 2002–2024. You could ask whether serve or return stats rise or fall in later rounds, which tournaments are unusually ace-heavy or return-friendly, and whether players' form shifts across seasons. The `_by_Rd`, `_by_Tournament` and `_by_Tournament_Surface` gold tables cover the round and tournament cuts directly. ## Caveats - The serve, return and raw tables have no detected join key, so each question has to be answered within a single table. - The serve table starts in 2006, while the raw and return tables start in 2013. Any multi-year trend that mixes them needs care. - 28 rows have a blank surface.