Natsu Banzuke Prediction Post-mortem

Two key criteria for developing good predictions are: (1) quantitative evaluation of the prediction and (2) accountability. With that in mind, I take a look at how my banzuke prediction performed.

Upper San’yaku was “chalk” as expected. In the lower San’yaku, I (and other predictions on this site) correctly had Yoshikaze filling the komusubi slot vacated by Shodai. I don’t understand the order of the three sekiwake ranks, as it appears unchanged despite the very different performances at Haru that had all of us predicting the order as Takayasu 1E, Kotoshogiku 1W and Tamawashi 2E.

In the maegashira ranks, of the 31 predictions, I had 11 “bulls-eyes” (correct rank and side” and 3 more correct rank predictions. This is way fewer than I expected or would have liked. The 17 misses were mostly not too bad: 13 missed by one rank, 3 missed by two ranks, and I had Osunaarashi (J1) moving up to M16 and Myogiryu (M15) dropping to J1.

There are three parts to the prediction: the computed ranks, tie-breaking among rikishi with identical ranks, and the departures I make from the computed ranks based on past banzuke patterns. Let’s look at these in turn.

The computed ranks were quite accurate: the official banzuke departs from these in only a couple of places. The computed rank would have Takarafuji at M3, but because of his make-koshi at that rank at Haru, the prediction and the banzuke moved him down to M4. Shodai (one of my two-rank misses) should be down at M7, and I still feel like the NSK cut him way too much slack after his 4-11 performance. And Arawashi and Ishiura would switch sides (but not ranks).

My tie-breaker was higher rank at Haru. This largely resulted in both of my other two-rank misses, as Takanoiwa should have been ranked above Tochiozan (and Aoiyama) by this rule. Presumably his 6-9 record at Haru led to his being dropped further down, although this is not necessarily consistent with past banzuke patterns. In a number of other cases, the tie-breaker got the relative order right, and I will need to look closely to see if the tie-break part of the prediction can be improved.

So, on to the departures from the computed rank order. One rule that resulted in many of my misses was to drop rikishi with 7-8 make-koshi records one spot from their rank at Haru, even if the computed rank would have them retaining their rank. This has often (but not always) been done in past banzuke. Although this rule correctly placed Takarafuji at M4, it placed Kagayaki, Tochinoshin, Ishiura and Daishomaru one slot too low, which also led to one-rank misses in the other direction for Ura, Arawashi, Kotoyuki and Onosho. It seems that the NSK is inconsistent in this scenario, and I’ll have to see if any pattern can be identified.

So overall, I am happy with my computed ranks, need to think more about the tie-break procedure, and need to be more careful with subjective departures from the computed ranks (this also includes demoting Myogiryu in favor of promoting Osunaarashi, even though Myogiryu had a better computed rank).

Others can chime in with how they fared. There will be another opportunity to predict the Nagoya banzuke after Natsu is the in books, and in the meantime we’ll have some actual sumo to watch!

Natsu Speculation Thread


A Reader Gave Us A Good Idea…

Reader Tom commented:

We should have a section on the blog for pre-basho predictions beyond the banzuke – who will win, who might impress/ struggle etc

Which is, in fact, a damn fine idea.  So post your speculation, no matter how wacky, in the comments, and I will pull the really good / fun ones up onto the page.

Associate Editor Bruce Writes:

After a startling first week that sees Yoshikaze in contention, Week 2 sees Kisenosato go kyujo with a re-inury to the pectoral. Goeido struggles to cope with his ankle injury, and in a day 13 in a bout with Terunofuji he re-breaks his ankle, and is forced to retire.  Yusho winner is Hakuho, after a win over Junyusho and Shin-Ozeki the mighty Takayasu.

Reader Andrew Michael Daley Writes:

Terunofuji, wearing a devil mask and entering to the strains of Black Sabbath’s “Iron Man” wins with a zensho-yusho but is denied promotion for a lack of “hinkaku”. Hakuho knocks at least one opponent (probably Yoshikaze or Tochiozan) spark out with a “honest it’s not an elbow” forearm smash.

Reader Rian Writes:

My prediction is that the healthiest Yokozuna/Ozeki wins, assuming that there is a healthy one. Wouldn’t it be nice to have a basho where injuries weren’t a major factor? Hakuho’s toe, Kakaryu’s back, Kisenosato’s chest, Terunofuji’s knee, Goeido’s ankle, and poor Harumafuji is probably held together with duct tape and bailing wire at this point.

Add your predictions – serious or insane, in the comments section.

Banzuke Weekend


After many weeks of meager sumo news, the start of another tournament cycle is upon us. That’s right sumo fans, this weekend we will get our first look at the official Japan Sumo Association banzuke.

Of course our contributors and commenters have all taken a stab at where the rikishi will be ranked, but there is no substitute for the real, genuine thing.

We anticipate it first appearing on the NSK site mid-afternoon US time, and there will likely be another Tachiai video podcast later that night featuring at least myself (and hopefully Andy) talking about the upcoming Natsu basho.

Stay tuned everyone, our coverage will shortly bounce back to active mode as we prepare for what should be a pivotal tournament.