Table tennis and the 'empty data' trap: when an analyst must learn to say 'I don't know yet'

In Shanghai, late at night, I reopened the match coding sheet and found the data column blank. The table was intact, every row had a name, but not a single number. For an analyst, that moment is scarier than a defeat: there is nothing to analyse, yet the page still lies there, waiting to be filled.

I sat in front of the screen for a long time. The reflex of the trade is to write it anyway — name a few players, assign a few metrics, build a story that sounds plausible. That temptation is stronger than outsiders imagine. An empty analysis gets sent back; a fabricated one still gets published, still gets shared, and only a few careful readers notice there is nothing inside. The danger of modern sports analysis is that empty data can still be written up as a conclusion.

Table tennis is a sport of small numbers. A rally lasts a few seconds, a spinning serve, a footwork step half a beat out of place — any of them can decide an entire set. That is why, when the data wave reached this sport, it arrived very fast.

In 2026, the ITTF launched World Table Tennis (WTT), restructuring the professional circuit along more commercial lines: more events, more ranking points, more matches streamed live. The result was an explosion in data on every athlete. Every serve, every point, every tactical switch mid-set can be recorded, coded and compared.

World table tennis has a clear centre of power. Across many Olympic Games, most men's and women's singles gold medals have gone to Chinese players; Ma Long won consecutive Olympic men's singles titles, a milestone no one has matched. But behind that wall, the gap is narrowing. Japan has Tomokazu Harimoto, Sweden has Truls Moregard, France has the Lebrun brothers — generations willing to trade rallies with the Chinese instead of retreating into defence. That is why data became an asset: whoever reads the opponent earlier gains an edge.

In Vietnam, we mostly follow world table tennis through the big matches, where only a handful of top players appear. But most of the truth of this sport lives in smaller events, where a world No. 40 grinds through qualifying. The data there is thinner, and that thinness makes writers prone to invention.

Over the past three years, I have followed WTT matches and taken notes differently from my commentary days. I count. I count how often a player actively changes the ball's direction in the first game, count the retreats to the middle of the table when pushed to the corner, count even the moments he stands still — because standing still is also a decision.

Every revolution begins with a number forgotten on a desk. For me, that number was once the touch count of a midfielder in the 2026 Shanghai derby, when I worked for a football club's analysis unit. But the same method, applied to table tennis, showed me something else: the winner is not the player who hits the most, but the one who forces his opponent to move the most.

It is a problem of space. Elite table tennis is no longer a duel between two paddles, but a duel between two maps of movement. A good player hides his rhythm; a better player reads that hidden rhythm before the ball leaves his opponent's hand. Data, here, does not measure feeling — it measures the consequences of feeling.

And this is where it is easiest to go wrong. A small sample always lies. If I take a player's last five matches and find a 70% win rate when serving short, I can write a tidy conclusion at once. But five matches are far too few to describe a skill; they are only enough to describe five specific opponents, in five specific situations. Ignore the circumstances, and the number becomes a lie dressed up neatly.

In every team, there are players the scoreboard never mentions. In table tennis, they are usually the doubles partner or the one who steps in for the third set, when the score is level. They do not score the decisive points, but they shape the situation that lets others score. A basic statistical table has no box for that kind of player; to see them you must rewatch the footage from the wide angle, and be patient.

That is why I increasingly believe that what viewers see on screen is not the real match. The real match happens in the gaps the camera forgets. In table tennis, those gaps are too small to see: a footwork step adjusting the centre of gravity, a wrist rotation, a glance toward the opponent's corner before a serve. Television does not show them, because they do not produce points immediately. But they produce points three seconds later.

I call it 'the first three seconds' — the span before the ball's path takes shape, when the match is truly written. The first three seconds of a set do not lie; the rest is just how we fool ourselves that everything is already clear.

The paradox lies here: the more data there is, the easier it is to forget that data is only a map, not the territory. A seasoned coach can watch a player warm up and know whether he is in form tonight — something no statistical table can capture. Data does not replace the intuition of an old coach. It only hands him a more accurate map.

Yet the industry still rewards confidence more than caution. An analysis willing to write 'not enough data to conclude' is harder to publish than one willing to assert. That pressure pushes analysts — and automated tools too — toward fabrication. When the input is empty, the machine still produces an answer, because it was designed to always have one. A wrong answer, neatly presented, spreads faster than a correct silence.

I am not writing this to recount a technical error of my own. I am writing because I believe table tennis, and sport in general, is entering a phase where the analyst's most valuable skill is not reading numbers, but knowing when to stop and say: I don't know yet.

If you have ever read a very confident analysis of a player you have never watched, try asking yourself three things: where the data came from, how big the sample was, and what was left out. Those three questions cost less than blind belief. In a sport decided by three seconds, perhaps the most honest moment for a practitioner is the moment he admits he has nothing in his hands.