The Empty Data Table: Notes from Vietnamese Volleyball

THE EMPTY DATA TABLE: NOTES FROM VIETNAMESE VOLLEYBALL

A Sheet of A4

On the night of 12 October 2026, at a provincial gymnasium in northern Vietnam, I sat in the third row of the press section. In front of me was a sheet of A4 paper. It had four columns: jersey number, player name, points, errors. That was all. No kill percentage, no attack efficiency, no block counts, no hitting map, no serve-rhythm distribution. Four columns, handwritten in blue ballpoint, and the writer had to stop twice in the middle of the third set because her hand was cramping.

In Tokyo, four thousand kilometres away, the same volleyball match would run through at least two parallel tracking systems. A single set generates roughly three hundred to four hundred data points. Forty minutes after the final whistle, the file is packaged and sent to four destinations: the organiser, the rights-holding broadcaster, the federation, and a company whose name appears on no news bulletin.

Two sheets of paper. One game.

I still keep that A4 sheet. Not because it is precious. Because it is honest. It states plainly something no data table dares to state: most of what happens on a volleyball court is not measured, and has never been attempted.

An Unprecedented Cycle, and a Notebook Never Opened

2026 marks a milestone Vietnamese volleyball has awaited for three decades. The women's national team qualified for the World Championship for the first time, staged in Thailand from 22 August to 7 September 2026, with an expanded field of 32 teams. Tran Thi Thanh Thuy, the captain, has played professionally in Japan since 2026, turning out for PFU Blue Cats and then Denso Airybees. Nguyen Thi Bich Tuyen has become a name regional scouts are forced to write down.

But that cycle did not begin with a data table. It began with amateur clips filmed from the stands, with a message from an acquaintance, with an assistant coach squeezed into a corner of the gym, counting by hand.

Meanwhile, on the other side of the volleyball world, the data industry had travelled very far ahead. Match-tracking software was born in Italy in the early 1990s, initially serving coaches themselves. By the 2010s, as volleyball entered the era of pay television and online betting, data detached from the technical meeting room and became a commodity with a price. The world governing body reformed its ranking system from 2026, shifting from tournament-based calculation to match-by-match calculation weighted by competition tier and opponent strength. Every ball that touches the floor in an international match moves a number on the global ranking, and that number decides qualification places, seeding, and prize money.

The asymmetry lies here. A Japanese athlete entering her nineteenth year already has a three-season data record: blocks per set, reception percentage, hitting distribution by zone, even laboratory-measured physical indices. A Vietnamese athlete of the same age, of the same potential class, has a DVD sent by an acquaintance.

That is the whole gap. It is not height, not vertical leap, not training hours. It is whether somebody was willing to sit down and write it up.

What the Table Measures, and What It Misses

I once believed in data tables with the purest naivety. In 2026, as a first-year student in Tokyo, I wrote a long piece about 800m runner Kenta Kikutani, who won the Japanese national athletics title in 1:47.23 but was criticised by the media for running too cautiously. I spent three days counting his stride frequency lap by lap and found he held 187 steps per minute across all four laps, while his main rival oscillated between 199 and 172. An editor at Athlete's Japan shared the piece. It drew more than 4,800 reads in 48 hours.

The lesson was not that running slowly wins. It was that a number only means something when the reader knows which stretch of the race it occupies. 172 steps per minute in lap one is laziness. 172 steps per minute in lap four is exhaustion. The same number, two fates.

Volleyball has not learned that lesson. And the official box score, even where investment is fullest, still contains at least four blind zones I have met again and again over years of watching.

First, attack kill percentage. This is the most quoted and most misunderstood metric. An outside hitter at 42 percent sounds like someone playing well. But where did that 42 percent come from? If two thirds of her attempts were high balls at position four against a two-woman block on the wing, 42 percent is excellent. If two thirds were quick balls through the middle after a perfect reception, 42 percent is worrying. The box score does not distinguish the two. It records one figure: 42 percent.

I once watched a head coach point at a stat sheet and pull a middle blocker because her kill percentage was low. Her replacement had a higher percentage, but only because she was fed the ball in favourable situations, after the opponent's reception system had collapsed. The team lost that set. The table could not see the cause. It saw only the outcome.

Second, service aces. This is the metric audiences love most, and the metric that most honestly reflects audience habit. An ace is a beautiful moment, easy to remember, easy to replay on television. But it is the visible tip of a measurable iceberg. A player serves twelve times, scores two aces, and in nine of the remaining ten forces the opponent to receive with two players instead of three, drags the setter away from the net, forces the middle blocker to run a decoy. Her ace count is lower than a teammate who served twelve times with three aces, but whose other eight serves were received perfectly and turned into quick attacks.

The box score calls the second player the better server. In reality, the first is playing a different game at a different level. But nobody can write that column. That column has no cell.

Third, perfect reception rate. The problem is definitional. Tracking systems around the world use different scales for the same concept. Some use five grades, some four, some merge perfect and positive reception into one cell on the grounds that the difference does not matter. The result is that two players can both show 58 percent, one measured with a long ruler and one with a short one.

Sitting beside a foreign team's analyst at an Asian tournament, I asked how he distinguished. He smiled and said he only trusted numbers he recorded himself, and he recorded with his eyes. Receiver stands firm, ball comes to hand, setter has three attacking options: perfect. Receiver must take two extra steps, ball comes to hand, setter has only two options: good. That difference never appears in a public data table. Yet it is the entire difference between a team reaching the semifinal and a team going home.

Fourth, successful blocks. This metric rests on a false assumption: that whoever touches the ball deserves the credit. In modern blocking systems, most scoring blocks do not come from the player nearest the antenna who touches the ball last. They come from the middle blocker who times her movement, bends the attack line toward the sideline, and leaves the wing blocker in a favourable posture. Or from a libero who reads the ball half a second early and is already standing in the right place.

The table credits whoever touched the ball last. That is the accounting method of an individual sport inside the body of a team sport.

Who Pays for Those Numbers

I remember a conversation at an international tournament with the data tracker seated by the sideline. He had a tablet, a headset, and an impressive typing speed. Every time the ball hit the floor, his fingers ran an unchanging key combination. I asked who he worked for, and he named a company I had never heard of.

Three months later I looked it up and found the company was a live data supplier, and its largest clients were international bookmakers. The same keystroke, in the same instant, feeds the federation for ranking calculation and feeds the betting market to adjust odds within seconds.

One keystroke, two markets.

This is the side effect the sports industry discusses very little. Digitisation has made every point instantly financially valuable. A 22-year-old middle blocker trying to dig a hard serve does not know that the movement of her wrist in that fraction of a second has shifted odds in a betting house twelve time zones away. She also does not know that this is precisely why an analyst on another continent may be reviewing her, not to sign her, but to price a contract she will never see.

I am not against tracking. I am against tracking that does not say who reads it. A system is only honest when it discloses its funding. Otherwise all those beautifully branded tables are just a form of financial intermediation wearing technical clothing.

The Vietnamese Gap

Back to the four-column A4 sheet.

For years I have held that Vietnamese volleyball suffers an asymmetric disadvantage in the international market, and that disadvantage has nothing to do with playing ability. It has to do with visibility. A Vietnamese player who wants to move abroad must clear an obstacle Thai or Japanese players do not face: nobody has a record of her.

Foreign clubs recruit through three channels. The first is official data from international competitions, which only works if the player has already appeared in one. The second is video sent by an agent, dependent on that agent's network. The third is live scouting, dependent on someone happening to sit in the gym on the very night the player performs at her best.

All three channels share one property: they do not reward the best player. They reward the player who is best at the moment someone is watching. That is a lottery, and no sport should be built on a lottery.

Japan does it differently. Its domestic league operates a public database where every match is standardised and published, with player-level indices attached. A coach in Italy can open that page and compare two middle blockers in ten minutes. This does not make Japanese volleyball prettier. It makes Japanese volleyball buyable.

That distance is the arbitrage market. And in sport, arbitrage is always a short-term opportunity. The first Vietnamese club to build a genuine data room, not for show but to sell its players' profiles outward, will hold an advantage for years. Not because it is better. Because nobody else is doing it.

A crack does not break the wall; it teaches us to see through it.

Transfer Window: Noise and Signal

Transfer season is when the data gap becomes most expensive.

In volleyball economies with a complete transfer system, the real story lies in three places: release clauses, club wage bills, and the remaining term of the current contract. The transfer fee is merely a figure published so the public has something to discuss. Those three factors decide whether a player can leave, and at what price.

I followed one Vietnamese player's move to a foreign league. For four months, newspapers in both countries reported on the transfer fee. The figure swung from very low to very high. None of them was correct. What actually decided the deal was a question nobody asked: does her current contract belong to the provincial sports centre or to the club? If it belongs to the centre, then every negotiation with a foreign club starts from a document no party knows how to value. Four months of argument over a figure that does not exist.

Here the institutional structure itself generates noise. When ownership is unclear, no database can save the negotiation. Nobody knows whose asset the player is, and that makes her price indeterminable.

During a transfer window, fans consume rumours because rumour is the cheapest form of entertainment. But if you want to understand the market, read in reverse order: contract first, wage bill second, rumour last. And if a piece of information has no signing date, no signing party, no clause structure, it is only noise. We in the trade live on noise, but we should not live inside it.

One Column and One Name

Based on my experience watching matches over the years, I have come to see that the most important moment in a volleyball match is rarely recorded in the table. It is the moment the whistle blows, the score is settled, and a player who has just made an error must walk off the three-metre line.

I remember one such night. She mishit the decisive ball of the fifth set. The box score will record an attack error. A red mark on the sheet. Nothing more.

But during the interval between sets three and four, she had sat down beside the bench and retied her shoelaces for the third time. The medical assistant had handed her an ice pack. And in the row behind, a middle-aged man holding a folder spoke to her for about forty seconds, crouching to her eye level, both hands on her shoulders. Those forty seconds appear in no data system on earth.

I wrote about that moment. Because I believe that if sport retains only what can be measured, it becomes a statistical discipline with people in jerseys. And nobody stays up until two in the morning to watch a statistical discipline.

N/A Is Data

In this profession I have received many reports where most cells read N/A. At first I treated that as failure. An empty data table is a useless data table. After years, I changed my view.

A cell reading N/A is a statement. It says that at this moment, in this place, nobody has measured that index yet. For a sport, the proportion of N/A in its own data table is a map of what it has not yet built. Not a map of what it is weak at. Weakness is a technical problem, fixable through training. Absence of data is a structural problem, and training cannot fix it.

The global sports industry believes the opposite. The prevailing faith is that finer data produces better decisions. That is true in the early stage. But at the margin, the seventy-fourth metric has negative marginal value. It does not clarify the picture. It creates a new picture competing with the old one and forces the decision-maker to choose.

I once watched a coach receive twelve indices on the same player, eleven good and one bad, and sit motionless for ten minutes. With three indices he would have decided long ago. More data does not produce confidence. It produces paralysis with a halo.

There is something worse than paralysis. It is reports filled in with estimates. When a cell is empty, the lazy analyst writes a guessed value into it. Three years later that guess is cited as a verified fact. Five years later it becomes historical data. Vietnamese volleyball has a few phantom statistics living exactly that life, born in somebody's notebook and now repeated routinely in articles nobody traces back.

I choose the opposite. In my own tables I keep the empty cells. And I write plainly that I do not know. Writing about what you do not know is far harder than writing about what you do. But it is the only form of honesty available in this trade.

There is another aspect I consider more worth discussing. If I only followed volleyball, I would think the data-gap problem was specific to volleyball. But looking at athletics and swimming, I see the same pattern repeating. In athletics, the calendar is so dense that athletes must trade ranking points against health. In swimming, technical indices are highly detailed but pre-race psychological indices are close to zero. Each sport chooses one zone to measure and one zone to leave blind. And all of them call their blind zone by another name: experience.

The best sports writers I have read are not those who remember the most numbers. They are those who know which numbers to throw away.

What Remains After the Numbers Vanish

The pen does not need a grandstand, only a quiet conviction.

Over ten years I have watched Vietnamese sport travel from a regional playground to the world ranking, and I believe the coming decade will not be decided by who buys the best software. It will be decided by who has the patience to record honestly what is happening, every night, every set, every season, for years, without anyone applauding.

When the stadium falls silent, we hear the game's pulse clearly. And in the years ahead, I want to hear that pulse inside a complete notebook, written by a Vietnamese hand, in a small provincial gymnasium, at eleven o'clock at night.

The A4 sheet I keep has four columns. I no longer see it as a lack. I see it as a starting point. And every great data table in the world, at some point, began with a blank sheet of paper just like it.