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

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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

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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.

Handicapping The Natsu Banzuke – Part 3

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The Fish Tank & Fresh Faces

*Updated after reader lksumo pointed out that my spreadsheet had somehow skipped special prize winner Takakeisho. This caused a complete re-compute of the lower 8 ranks.

In the last of our series prognosticating the banzuke for Natsu, we take a look at the lower half Makuuchi, including the rikishi who are likely to be demoted down to Juryo and promoted out of Juryo to the upper division.

As stated in the prior posts, the records at the end of Haru left a chaotic mess for predicting the Natsu banzuke. There were a number of strong finishers in Juryo, and a lot of losing records in Makuuchi. In fact the lower Maegashira suffered a preponderance of losing records, and in fact it was difficult this basho not to promote rikishi with losing records, simply because there were so few winning records, and most of those had already moved up the banzuke into upper Maegashira.

Gone from the upper division is Nishikigi, who had been a lower Maegashira for some time. He will go back to Juryo to adjust and try again. His rank velocity was a horrific -7.5, as he went 5-10 in March. Also back to Juryo is Chiyoo, who was injured and withdrew on day 11, after already having secured his make-koshi. We hope he has recovered and is ready to dominate in Juryo.

Also gone from Maegashira is Sadanoumi who had a 4-11 record in March. His rank velocity was -7, and he was tagged for a return to Juryo fairly early on. Joining him is Mongolian Kyokushuho, whose 5-10 record from Maegashira 14 was his ticket back to the second division.

Joining Makuuchi from Juryo is a set of hard charging rikishi ready to compete in the top division. Chief among these is Juryo yusho winner Toyohibiki, who returns after a single basho in Juryo. Tachiai also predicts that veteran Chiyotairyu’s winning record will return him to lower Maegashira as well.

We also predict that Onomatsu beya’s Onosho will be making his Makuuchi debut. This up-and-comer has been in Juryo for 13 tournaments, and finally appears to be ready to join the top division. When filling in the banzuke, it was clear that there needed to be one more name kept in Makuuchi, or brought up from Juryo. I am going out on a limb here, but I am going to predict that Osunaarashi will make his return once more to the top division.

Running everyone’s scores through the magic computations gives us the following list:

East Rank West
Hokutofuji Maegashira 8 Shohozan
Arawashi Maegashira 9 Ichinojo
Kagayaki Maegashira 10 Ura
Tochinoshin Maegashira 11 Toyohibiki
Ishiura Maegashira 12 Onosho
Kotoyuki Maegashira 13 Tokushoryu
Chiyotairyu Maegashira 14 Kaisei
Daishomaru Maegashira 15 Oyanagi
Osunaarashi Maegashira 16

First up at Maegashira 8; Hokutofuji, who drops 2 ranks after turning in his first career losing record. Hokutofuji displays significant skill, strength and fighting spirit. I am going to assume that he will start Natsu with a burning desire to continue his march up the banzuke. At 8 west we find Shohozan, who is part of Kisenosato’s dohyo-iri team. He drops 5 places from Maegashira 3, after receiving a brutal pounding in March.

At Maegashira 9 we find Arawashi who suffered a 5 rank demotion after going 4-11. Arawashi has a lot of potential, but for some reason he was out of his element in Osaka. Joining him is Mongolian giant Ichinojo, who drops from Meagashira 7. In spite of a strong losing record, he was actually less terrible than some of his peers, so his demotion is less severe.

Journeyman Kagayaki, who is still struggling to put together a winning plan for surviving his Makuuchi bouts, holds the east slot for Maegashira 10. Ura was one of the few bright spots in March’s lower Maegashira, and he rises 2 ranks to take the west slot of the 10th rank.

Leading Meagashira 11 is Tochinoshin, who has been seriously hurt for a few tournaments now, and is a shadow of his former self. Juryo yusho winner Toyohibiki joins in the west slot, and we predict he will feel right at home resuming his Makuuchi duties after a single basho in Juryo.

Ishiura has been struggling to put together a consistent winning strategy for Makuuchi. His compact size, excellent speed and outstanding strength supply him with a lot of building blocks, but we wait for him to come up with a knock-out combination that shows us what he is really capable of. I suspect he may be getting ready to bounce back from a pair of somewhat disappointing tournaments. Joining him, Onosho makes a strong Makuuchi debut at the rank of Maegashira 12.

Kotoyuki, falls 4 ranks given his dismal 5-10 results from the Haru basho to Maegashira 13. Computationally, I suspect that Kotoyuki will be further down the banzuke, but at the present my calculations are a bit fuzzy on where the Juryo promotees will be inserted into Makuuchi. At 13 west, Tokushoryu, who was one of the few kachi-koshi sumotori from March. He gets a bump up 2 ranks and hopefully can turn in a second winning record in May.

For Maegashira 14, Chiyotairyu returns from a single basho in Juryo. He achieved a winning record from Juryo 1 rank, and will return to Maegashira for May. On the west, we find Kaisei still hanging on to a bert in the top division. Kaisei sat out several days of Haru with injuries, and then joined and had a miserable time of it. Somehow this guy is able to evade demotion to Juryo every time, and I predict that he will somehow survive yet again, albeit at a much lower rank.

Daishomaru drops two ranks to Maegashira 15, after a 7-8 result in Osaka. If he has another losing record he will likely return to Juryo to tune himself up. Bring promoted from Juryo is Oyanagi. This will only be his 8th basho! Oyanagi has experienced a meteoric rise, and is now in Makuuchi after only 3 tournaments in Juryo.

Bringing up the final slot in Makuuchi, is my wish-casting of yet another return of the sandstorm, Osunaarashi, to Maegashira. His last Maegashira appearance saw Osunaarashi become injured, and unable to compete strongly. I will be surprised to see him actually re-joing the top division, but as stated earlier, the lower end of Makuuchi ranking was very difficult this time.

That’s Bruce’s guess for Natsu 2017. As always, please feel free to post your ideas too!