Category Archives: notation

Tokyo Grand Slam Metrics.

As per previous posts, I have been working on a project to collect data from the IJF scoreboards and store them in a database for later study. In this article I want to share some information I have gained from the 2012 Tokyo Grand Slam.

 

In the last article we looked at day one, in this article we will look at the entire event and discuss a couple of points that come up.

 

How much actually happens at a Grand Slam?

The 2012 Tokyo Grand Slam was a three day event, spread across 3 mats in the elimination rounds. The semi-finals and finals being held on one mat after a two hour break. In total the scoreboards recorded 1,013 changes to the scoreboards. That includes corrections to scores as we have discussed in earlier articles on this website.

The scoring broke down like this:

  • Minute 1: 111
  • Minute 2: 176
  • Minute 3: 160
  • Minute 4: 160
  • Minute 5: 163

 

The Ippons broke down like this:

  • Minute 1: 22
  • Minute 2: 27
  • Minute 3: 31
  • Minute 4: 35
  • Minute 5: 45

Out of those 160 Ippon scores, only 6 were in Golden Score with there being a total of 30 scores in golden score time.

 

A very simple look at the numbers above can suggest that it is in minute 2 you are most likely to be scored against and caught for Ippon most often in the final minute.

 

As per previous posts, the problem with this basic analysis of the 2012 Tokyo Grand Slam is that the data is never as simple as it looks. The software captures every change to the scoreboard and stores it as a record. So the moment the table official hits the Ippon button the database gains an Ippon. Unfortunately errors happen and when the referee changes the score the database gaisn another record but not losing the original Ippon. This means it is hard to use data in the way shown above, especially for scores lower than ippon that don’t stop the match.

 

It is good to collect that data however, we could with relative ease determine how many scoring errors were made. A cursory examination for example shows 154 Ippons on the official record, where the captured data shows 160. So Ippon was put on the scoreboards incorrectly 6 times across three days.

 

We can also look at things like the actual time contests started. The system captures the clock at 5:00 minutes, i.e. the start of the match as the names come on the scorebaord. We can easily collect the timestamps from these records and see for example the distribution of starts across the three days.

  • 11:xx 66
  • 12:xx 72
  • 13:xx 56
  • 14:xx 8
  • 15:xx 0
  • 16:xx 9
  • 17:xx 21
  • 18:xx 11

 

Contests per hour Tokyo Grand Slam 2012
Contests per hour Tokyo Grand Slam 2012

 

What we can see is that the competition (across the three days) had the most fights occur between 12 noon and 1pm. This is a 3 mat event, that in the finals section went to a single mat with a break between elimination and finals.

It would be interesting to look at what scores happened in that 12-1 hour. Perhaps there were more Ippons in this period?

This very brief investigation into the data from the event is provided purely to encourage discussion and investigation by others, I know there are real statisticians out there who could dig out interesting information from the numbers. For me this event was mainly about testing the reliability of the data capture and preparing for the next stage where I shall be doing data collection using a Raspberry Pi computer.

I would love to hear your thoughts and opinions.

Lance

Qingdao Judo Grand Prix 2012 data, day two.

Today was the heavier weights here in Qingdao, so when looking at the data perhaps there is a difference in the pattern to that from day one?

Day 2 (-70, -78, +78, -81, -90, -100, +100), Opening Rounds:

Total Scores: 139

Scores in 1st minute: 21
Scores in 2nd minute: 34
Scores in 3rd minute: 34
Scores in 4th minute: 37
Scores in 5th minutes: 13

Ippon scores in 1st minute: 6
Ippon scores in 2nd minute: 6
Ippon scores in 3rd minute: 9
Ippon scores in 4th minute: 10
Ippon scores in 5th minutes: 5

Day 2 (-70, -78, +78, -81, -90, -100, +100), Gold Medal Fights:

Total Scores: 19

Scores in 1st minute: 1
Scores in 2nd minute: 4
Scores in 3rd minute: 4
Scores in 4th minute: 6
Scores in 5th minutes: 4

Ippon scores in 1st minute: 1
Ippon scores in 2nd minute: 0
Ippon scores in 3rd minute: 1
Ippon scores in 4th minute: 2
Ippon scores in 5th minutes: 2

 

It is also worth noting that the numbers quoted here include all changes to the IJF scoreboards, so includes scores later changed. The minute times mentioned include the golden score as well; so again care must be taken when interpreting the numbers. All this data is included in a database should people be interested in doing some research and analysis.

Of course this is a small sample, but it is interesting none the less to look at the numbers and especially to look at the differences between light and heavy. We need to consider also where we are in the Olympic cycle and how that affects the players attending the event and the level of preparation and focus they might have on the day.

Your comments on this are invited and appreciated.

Preliminary rounds, results:

GP_CHN2012 -100kg Mat:2 2:57 NUNES, Renan (BRA) 100(1)-000(0) DORJ, Anar (MGL)
GP_CHN2012 -100kg Mat:2 2:50 BAUZA, Karolis (LTU) 100(1)-000(0) XU, Xin (CHN)
GP_CHN2012 -81 kg Mat:1 2:04 KHABACHIROV, Murat (RUS) 001(1)-000(1) CHO, Seung Kwon (KOR)
GP_CHN2012 -70 kg Mat:3 0:58 CHEN, Yun-Ting (TPE) 100(0)-000(0) KAUR, Gagandeep (IND)
GP_CHN2012 -100kg Mat:2 2:28 ASANUMA, Takumi (JPN) 000(0)-100(0) XU, Jie (CHN)
GP_CHN2012 -70 kg Mat:3 1:51 MERLI, Nadia (BRA) 000(0)-100(0) OSUMI, Yuka (JPN)
GP_CHN2012 -100kg Mat:2 2:14 MAGOMEDOV, Shamil (RUS) 001(1)-100(2) KIM, Do Hyoung (KOR)
GP_CHN2012 -81 kg Mat:1 0:00 OTGONBAATAR, Uuganbaatar (MGL) 011(0)-000(0) EBI, Yasuhiro (JPN)
GP_CHN2012 -70 kg Mat:3 4:08 VARGAS KOCH, Laura (GER) 110(0)-000(0) CHEN, Rong (CHN)
GP_CHN2012 -81 kg Mat:1 4:24 DAVIS, Thomas (GBR) 100(0)-000(0) GAO, Haiyuan (CHN)
GP_CHN2012 -100kg Mat:2 1:46 CORREA, Luciano (BRA) 100(0)-000(1) ZHAO, Dongming (CHN)
GP_CHN2012 -81 kg Mat:1 3:06 PENALBER, Victor (BRA) 101(0)-000(2) KUMAR, Manoj (IND)
GP_CHN2012 -100kg Mat:2 3:52 KUMAR, Pramod (IND) 000(0)-100(0) KUMASHIRO, Yusuke (JPN)
GP_CHN2012 -70 kg Mat:3 0:00 HAN, Weiyan (CHN) 010(1)-000(3) YOU, Mee Won (KOR)
GP_CHN2012 -81 kg Mat:1 2:23 WU, Wen Shun (TPE) 000(0)-101(0) WANG, Xuewen (CHN)
GP_CHN2012 -100kg Mat:2 3:56 YUAN, Jinling (CHN) 100(0)-000(0) HONG, Yi Chih (TPE)
GP_CHN2012 -81 kg Mat:1 2:42 GAN, Tuvshinjargal (MGL) 101(0)-000(2) TURABOEV, Bekzod (UZB)
GP_CHN2012 -100kg Mat:2 1:14 LIM, Seung Rok (KOR) 000(1)-100(1) HUSSAIN, Shah (PAK)
GP_CHN2012 -78 kg Mat:1 4:01 YANG, Xiuli (CHN) 001(0)-100(0) HIDAKA, Misaki (JPN)
GP_CHN2012 -70 kg Mat:3 0:00 TSEND AYUSH, Naranjargal (MGL) 000(1)-000(0) ZHOU, Chao (CHN)
GP_CHN2012 -90 kg Mat:2 2:25 SINGH, Avtar (IND) 000(1)-100(0) ZHANG, Jun (CHN)
GP_CHN2012 -78 kg Mat:1 1:13 ZHANG, Jie (CHN) 100(0)-000(0) HSU, Hsin-Mei (TPE)
GP_CHN2012 -78 kg Mat:1 4:04 VELENSEK, Anamari (SLO) 100(0)-000(0) CHEN, Ying (CHN)
GP_CHN2012 -78 kg Mat:1 3:15 WANG, Szu-Chu (TPE) 000(0)-100(0) HAN, Li (CHN)
GP_CHN2012 -70 kg Mat:3 0:15 POGACNIK, Anka (SLO) 001(0)-110(1) TAKAHASHI, Rui (JPN)
GP_CHN2012 -90 kg Mat:2 0:00 KIM, Kwang-Ho (KOR) 001(1)-000(2) ZHANG, Zhongbo (CHN)
GP_CHN2012 -81 kg Mat:1 2:18 KHABACHIROV, Murat (RUS) 111(0)-000(0) ZHANG, Wentao (CHN)
GP_CHN2012 -100kg Mat:2 1:43 NUNES, Renan (BRA) 100(1)-000(0) BAUZA, Karolis (LTU)
GP_CHN2012 +100kg Mat:3 0:30 ULZIIBAYAR, Duurenbayar (MGL) 000(0)-100(0) WANG, Quanchao (CHN)
GP_CHN2012 +78 kg Mat:3 5:00 QIN, Qian (CHN) 100(0)-000(0) WOO, Jung-Min (KOR)
GP_CHN2012 -100kg Mat:2 1:53 XU, Jie (CHN) 000(2)-101(0) KIM, Do Hyoung (KOR)
GP_CHN2012 -81 kg Mat:1 1:35 OTGONBAATAR, Uuganbaatar (MGL) 001(0)-000(2) DAVIS, Thomas (GBR)
GP_CHN2012 +78 kg Mat:3 0:00 WANG, Rui (CHN) 002(1)-000(0) ICHIHASHI, Suzuka (JPN)
GP_CHN2012 -81 kg Mat:1 0:00 PENALBER, Victor (BRA) 001(0)-000(2) WANG, Xuewen (CHN)
GP_CHN2012 -100kg Mat:2 0:00 CORREA, Luciano (BRA) 000(2)-001(0) KUMASHIRO, Yusuke (JPN)
GP_CHN2012 +78 kg Mat:3 0:00 ALTHEMAN, Maria Suelen (BRA) 000(2)-002(0) LI, Yang (CHN)
GP_CHN2012 -100kg Mat:2 2:43 YUAN, Jinling (CHN) 101(0)-000(0) HUSSAIN, Shah (PAK)
GP_CHN2012 -81 kg Mat:1 1:57 GAN, Tuvshinjargal (MGL) 001(1)-100(2) LI, Maojian (CHN)
GP_CHN2012 -70 kg Mat:3 1:52 PORTELA, Maria (BRA) 100(0)-000(1) CHEN, Yun-Ting (TPE)
GP_CHN2012 -90 kg Mat:2 3:49 SULEMIN, Grigorii (RUS) 002(4)-100(0) ZHANG, Jun (CHN)
GP_CHN2012 -90 kg Mat:2 0:54 LI, Kunpeng (CHN) 000(0)-101(0) HUH, Chae Goo (KOR)
GP_CHN2012 -78 kg Mat:1 0:00 HIDAKA, Misaki (JPN) 001(0)-000(2) CHOI, Mi-Young (KOR)
GP_CHN2012 -70 kg Mat:3 0:00 OSUMI, Yuka (JPN) 000(1)-100(1) VARGAS KOCH, Laura (GER)
GP_CHN2012 -90 kg Mat:2 0:00 KIM, Kwang-Ho (KOR) 001(1)-000(2) LKHAGVASUREN, Otgonbaatar (MGL)
GP_CHN2012 -78 kg Mat:1 1:29 JUNG, Da Woon (KOR) 010(1)-000(1) ZHANG, Jie (CHN)
GP_CHN2012 -78 kg Mat:1 4:44 VELENSEK, Anamari (SLO) 100(0)-000(0) CHONGTHAM, Jina Devi (IND)
GP_CHN2012 -70 kg Mat:3 0:54 CHEN, Fei (CHN) 001(1)-000(2) HAN, Weiyan (CHN)
GP_CHN2012 -90 kg Mat:2 0:00 CHENG, Xunzhao (CHN) 010(1)-001(0) KITANO, Yuichi (JPN)
GP_CHN2012 -78 kg Mat:1 1:47 POWELL, Natalie (GBR) 010(1)-100(0) HAN, Li (CHN)
GP_CHN2012 -70 kg Mat:3 3:15 ZHOU, Chao (CHN) 100(0)-000(0) TAKAHASHI, Rui (JPN)
GP_CHN2012 +100kg Mat:3 1:42 PASKEVICIUS, Marius (LTU) 100(0)-000(0) WANG, Zhen (CHN)
GP_CHN2012 +100kg Mat:3 4:08 WANG, Quanchao (CHN) 100(0)-000(0) LEE, Po Yen (TPE)
GP_CHN2012 +100kg Mat:3 0:00 SAIDOV, Renat (RUS) 001(1)-000(2) SHEN, Zhuhong (CHN)
GP_CHN2012 +100kg Mat:3 1:05 KIM, Soo-Whan (KOR) 000(2)-001(1) WANG, Qiang (CHN)

Semifinals:

GP_CHN2012 -81 kg Mat:2 0:46 KHABACHIROV, Murat (RUS) 001(0)-000(1) OTGONBAATAR, Uuganbaatar (MGL)
GP_CHN2012 -81 kg Mat:2 2:00 PENALBER, Victor (BRA) 100(0)-000(0) LI, Maojian (CHN)
GP_CHN2012 -70 kg Mat:2 2:29 PORTELA, Maria (BRA) 002(0)-001(0) VARGAS KOCH, Laura (GER)
GP_CHN2012 -70 kg Mat:2 0:00 CHEN, Fei (CHN) 010(1)-000(3) ZHOU, Chao (CHN)
GP_CHN2012 -90 kg Mat:2 0:00 ZHANG, Jun (CHN) 001(0)-000(1) HUH, Chae Goo (KOR)
GP_CHN2012 -90 kg Mat:2 2:36 KIM, Kwang-Ho (KOR) 000(0)-100(1) CHENG, Xunzhao (CHN)
GP_CHN2012 -78 kg Mat:2 0:51 HIDAKA, Misaki (JPN) 000(2)-001(0) JUNG, Da Woon (KOR)
GP_CHN2012 -78 kg Mat:2 4:24 VELENSEK, Anamari (SLO) 100(0)-000(0) HAN, Li (CHN)
GP_CHN2012 -100kg Mat:2 0:00 NUNES, Renan (BRA) 002(0)-001(1) KIM, Do Hyoung (KOR)
GP_CHN2012 -100kg Mat:2 0:00 KUMASHIRO, Yusuke (JPN) 001(1)-000(0) YUAN, Jinling (CHN)
GP_CHN2012 +78 kg Mat:2 2:54 QIN, Qian (CHN) 101(0)-000(0) WANG, Rui (CHN)
GP_CHN2012 +78 kg Mat:2 0:00 LI, Yang (CHN) 000(2)-001(1) YU, Song (CHN)
GP_CHN2012 +100kg Mat:2 2:09 PASKEVICIUS, Marius (LTU) 110(0)-000(1) WANG, Quanchao (CHN)
GP_CHN2012 +100kg Mat:2 0:00 SAIDOV, Renat (RUS) 010(2)-001(3) WANG, Qiang (CHN)

Gold Medal Fights:

GP_CHN2012 -81 kg Mat:2 2:43 KHABACHIROV, Murat (RUS) 000(0)-100(0) PENALBER, Victor (BRA)
GP_CHN2012 -70 kg Mat:2 1:59 PORTELA, Maria (BRA) 000(1)-100(1) CHEN, Fei (CHN)
GP_CHN2012 -90 kg Mat:2 1:27 ZHANG, Jun (CHN) 000(1)-100(1) CHENG, Xunzhao (CHN)
GP_CHN2012 -78 kg Mat:2 0:00 JUNG, Da Woon (KOR) 000(2)-102(0) VELENSEK, Anamari (SLO)
GP_CHN2012 -100kg Mat:2 4:41 NUNES, Renan (BRA) 000(0)-100(0) KUMASHIRO, Yusuke (JPN)
GP_CHN2012 +78 kg Mat:2 0:00 QIN, Qian (CHN) 000(1)-000(1) YU, Song (CHN)
GP_CHN2012 +100kg Mat:2 0:04 PASKEVICIUS, Marius (LTU) 110(2)-001(1) SAIDOV, Renat (RUS)

 

 

 

Qingdao Grand Prix 2012 data, day one.

In this article are some simple statistics gathered at the 2-12 Qingdao Judo Grand Prix.

Day 1 (-48, -52, -57, -63, -60, -66, -73), Opening Rounds:

Total Scores: 227

Scores in 1st minute: 43
Scores in 2nd minute: 45
Scores in 3rd minute: 57
Scores in 4th minute: 48
Scores in 5th minutes: 34

Ippon scores in 1st minute: 11
Ippon scores in 2nd minute: 7
Ippon scores in 3rd minute: 11
Ippon scores in 4th minute: 13
Ippon scores in 5th minutes: 6

Day 1 (-48, -52, -57, -63, -60, -66, -73), Gold Medal Fights:

Total Scores: 36

Scores in 1st minute: 3
Scores in 2nd minute: 7
Scores in 3rd minute: 13
Scores in 4th minute: 5
Scores in 5th minutes: 1

Ippon scores in 1st minute: 1
Ippon scores in 2nd minute: 2
Ippon scores in 3rd minute: 4
Ippon scores in 4th minute: 1
Ippon scores in 5th minutes: 0

The data here includes all scores on the IJF scoreboards, including those later changed which is important to consider. Tomorrow are the heavier weights, so it will be interesting to see if the distribution is similar or not.

 

When do people score in Judo?

Below is a screen shot that shows some very basic information on the heavyweight divisions at the 2012 European Junior (under 20 years) Championships, held recently in Porec, Croatia.

EC_JUN2012
EC_JUN2012 Scores

 

As you can see, the under 20 championships duration is 4 minutes. The least amount of scoring happens in the first minute, the most in the second minute of the match.

The number of Ippon throws varies minute by minute also. With the last minute of the match being an area of interest. There is proportionately more Ippon scores during the final minute than any other period in the match. The reasons for this we do not know. And this is from a single event.

We can also see that there were 512 scores made in this incomplete dataset, of which Ippon made up approximately 22% of the scores.

As with all statistics, the size of the sample set is important. In this case it is extremely small. This is a dataset collected with a new experimental solution and was only used on one day of the event. We need to consider a much larger sample before putting much weight in these figures; I put them here purely to invite discussion.

 

Have the new 2010 rules affected Judo?

Nage pointThis past weekend we entered the official qualification period for the London 2012 Olympic games. In this qualification period the new rule changes are in effect (and are not supposed to change) and it is worth taking a brief look to see if the changes are having an effect on the Judo being played. In this post, we shall compare data from the 2009 Moscow Grand Prix and last weekend’s 2010 Tunis Grand Prix.

If you recall, last year we looked at the 2009 Moscow Grand Prix on this blog ( http://judometrics.com/2009/06/moscow-judo-grand-slam-2009-data/ ) using data from www.ippon.org on the scores and penalties awarded in that event. In this post we shall look at the same data, from the same source, from the 2010 Tunis Grand Prix.

In 2009 we found that Ippon made up 77% of the throwing scores in male Judo and 39% of the female throws. In 2010 we find that Ippon makes up 75% of Male throws and 55% of female throwing scores. Thats a decreaqse of 2.40% in men, but a 15.44% increase in Ippon scoring throws in womens Judo.

Within mens Judo we se a 8.10% decrease in Wazari scoring throws and a 10.49% increase in Yuko scoring throws. On the opposite side, womens Judo has decreased the number of Warazi (9.74% decrease) and Yuko (5.70% decrease) throwing scores.

Looking at the number of penalties per match, we see that in 2009 it was 1.61 penalties per match and 1.84 in 2010 for men. The women had 1.39 penalties per match in 2009 and 1.51 penalties per match in 2010. Looking at the scores per match, they have changed very little between 2009 and 2010 (.56->.59 for men, .78->.79 for women). If we look at direct Hansoku Make penalties, unsuprisingly we see the men go from 1 in 2009 to 11 in 2010. The females also increased their Hansoku Make from 0 in 2009 to 2

So to summarise, in men’s Judo we have fewer Ippon and more penalties. Women’s Judo on the otherhand has more Ippon throws and more penalties. BOth men and women have an increase in Hansoku Make, which we can presumably associate with the new leg grab rule.

This very brief look at the data gives only a snapshot of elite Judo from two events; two events in Europe. So we can’t and shouldn’t read too much into the numbers. This data does not look at the style of Judo on display. It is perfectly possible that the Judo shown in 2010 is more exciting and “pure Judo”.

However, these numbers do provide a view of Judo that we need to consider. My understanding was that the rule changes were devised to increase/promote throwing Judo. “Pure Judo” as it was phrased. My interpretation is that this has arguably been the case in Women’s Judo a 15.44% increase in the Ippon statistic is very positive.  But the general trend towards even more penalties is a negative; this might be a result of the rule changes, or different fighting styles; we can’t tell from this examination.

If we look broadly, the number of scores per match has increased in both men and women, as has  the number of scores from throws; from 1.61 to 1.86 per match for men and 1.67 to 1.86 per match for women. However, the number of scores per match from throws has only increased from .56 to .59 for men and .78 to .79 for women.

More investigation is required, an investigation into the style of Judo displayed would be interesting; as would a long-term study of the objective data over a wide range of events.

How do you feel the Judo from 2009 and 2010 has changed? How do you feel the rule changes have affected Judo? How do you think we can further explore the area?

Attack rates in Judo.

The following post is another summary of the work done by Dave Elmore of Wolverhampton University, who is a colleague of mine on the University of Bath Foundation degree. This piece of research was done as part of the Bath course and Dave has kindly allowed me to share it here. For those not aware of the course at Bath, it is a fantastic learning opportunity for any person dedicated to Judo. It covers everything from the Origins and HIstory of Judo to the latest scientific research and modern Judo waza, not to forget Kata also. Applications for the 2010 intake are open now, so please do visit the website and consider signing up.

Scores at 2008 Prague Judo World Cup

What the chart above shows us very simply is when scores were achieved in matches at this event, broken into 30 second segments. This chart is based on the toal number of score across categories. You can see that during the 21-90 second mark the number of scores is reaches a peak, then drops off; followed by another peak at 271-330 seconds.

This data can be interpretted in a number of ways as players, coaches, physiologists and analysts. Tactically, we can look at this and suggest that our training programmes need to prepare our Judo athletes to expect higher work rates at these two peaks. Strength and Conditioning be it in the gym or in the Dojo could be modelled around the structure shown in the chart.

Of course there is more to the story than this, we need to look deeper before making radical changes to our training regimes.
For example, we need to look at the weight category that your Judo athletes are competing in, below are chart is from the -60kg and +100kg categories, does it tell a different story?

Scores Vs. Time 2008 Prague Judo World Cup

The above chart shows some differences between weight categories that are interesting. The +100kg category shows a marked drop off in scoring after the peak at 151-180 seconds. The -60kg players appear to show a more consistent scoring pattern across the duration of the matches. This may be purely due to the physical characteristics of the players in these weights, we do not know.

Both the charts above include all scores in the matches, which is interesting but argueably less interesting that when the decisive, winning score occurs in a match. Luckily, we have this information too.

Winning Scores vs. Time

The chart above suggests that there is a period of risk after around one minute, around three minutes and finally near the end of the match. The numbers of scores in these “hot spots” increases as the match goes on. The “dips” may indicate periods where players are resting? Perhaps we can train players to attack in the dips, where the majority of players are not scoring? This is one perspective of the data at least. Again this is data covering all attacks and all categories, lets look more closely at the data for individual categories.

Judo -60kg winning scoresThis chart shows when the scores that won the matches occured in the -60kg category of the 2008 Prague World Cup. From this we can infer that the period from 211 seconds through 300 seconds is the “hotspot” at which point you are at the greatest risk of being scored against (or of course you have the greatest opportunity for scoring). Players can be trained (potentially) using methods that capitalise on this identified “hotspot”.

Here, for the first time we also see shat scores are occurring when. Shido is sadly the most common score. Let us now look at a entirely new category, the -81kg category.

picture-4This chart of the -81kg category of the 2008 Prague World Cup shows a very different shape to matches. Here there appears to be a steady increase in scoring up to the 181-210 mark, at which there is a sharp decline. There are a variety of ways this information might be used; perhaps if your athletes can be trained to withstand the onslaught leading up to the 211 seconds mark they might profit from planning their own barrage later in the match?

What is also interesting in this category is the large gap between Shido and Ippon scores and Wazari, Yuko and Koka scores. There is also what looks like a clear relationship between the Ippon and Shido scores, the peaks are consistently at the same places. What does this suggest? Why is there a difference between this category and the -60 fighters?

Perhaps at this point it is worth considering the overall scoring rate again, but look at the individual scores rather than an amalgamated chart:

Scores vs. Time

This chart shows some interesting data that might be of interest. For example, the jump in Shido scores at 271-300 might show the penalties that accrue as a player ahead on points defends their lead at the end of a match. It is also clear that Shido is the top socre in this event, followed by Ippon, Wazari, Yuko and lastly Koka.

Perhaps it is data like this that served as proof to the IJF to scrap the Koka in international competition, seeing as it is clearly the least frequest score. Perhaps now that Yuko incorporates (some) Koka a future investigation might have Yuko more frequent than Wazari?

In terms of player preparation, can we apply what the data shows us? Should we be teaching/training Koka Judo? Is it an effective use of training time? Even at the “golden score” (301-420) stage of the fight Koka is infrequent. Should more time be dedicated in training to preventing or generating Shido?

The data from this study is fascinating, and it is interesting to consider the implications it might have in modern Judo preparation and competitive tactics and strategy. This sort of study and our own analysis of it in terms of our own specific situations may highlight potential changes in training or performance Judo that we can implement.

To close, I would like to thank Dave Elmore once more for sharing the data he collected with me and allowing me to share it online. Dave is doing great work which is not only statistical in nature. here in the UK he is perhaps better known for his work in the Advanced Aprenticeship In Sporting Excellence JUDO (and blog). If anyone is interested in enrolling for this course in September 2009 here is a document which gives more information and contact info: what-is-aase-word-doc.

Lance.

The anatomy of an elite level Judo match (Craig Fallon at 2003 European Judo championships).

Craig Fallon
Photo by M Lee

Recently a colleague of mine sent me a study he conducted some time back observing British fighter Craig Fallon in action at the 2003 European Championships. Dave Elmore analysed all the fights Craig had on the day against Paischer, Uematsu, Morokhovets, Nazaryan and Khergiani. He carefully recorded the time spent in the following categories:

  • Adjusting Judo Gi
  • Gripping
  • Ne – Waza (grappling)
  • Hajime
  • Matte
  • Attacking – Tachi – Waza
  • Defending Tachi – Waza

Dave is the Judo Development officer at the University of Wolverhampton in the UK. He also runs the very good Advanced Apprenticeship Judo Blog. He looked at the data on a fight by fight basis and also overall, which produced the following chart:

As you can see from the chart, very little time was spent by Craig Fallon attacking in Tachi Waza. A majority of the matches was taken up with Ne Waza, Kumi Kata and adjusting Judo suits. Of the 19 minutes and 23 seconds spent in the competition, only 33 seconds of that time was actual attempts at throwing. Now there are lots of reasons for this, not least of all the speeed at which attacks happen. What stands out is the percentage of time that Craig spent fighting for a grip (29.41%), which shows the importance kumi kata perhaps.

31.30% of Craig Fallon’s time was spent in Ne Waza, it would be interesting to conduct a wider study looking at an entire category or event to see if this is a feature of Craig Fallon’s Judo or of light weight Judoka, or not.

The amount of time spent adjusting the Judo suits is also an eye opener, not an area of Judo that I have seen recorded before and as the chart shows quite a large part of the fight was spent just getting dressed (26.57%). Again this may be a feature of the fighting style of Craig and his opponents, it would be interesting to see if this amount of time is consistent across weights and genders.

If these numbers were to be proven to be standard across Judo, then it would have implications for coaching. Kumi Kata is growing in acceptance as an important skill that must be practised, this study supports this idea. This study could be used to justify increasing the amount of time drilling and practising kumi kata in club training sessions.

The amount of time spent adjusting the Judo Gi may also be important in terms of recovery time between segments of action during a match. Further study might provide suggestions to train for shorter bursts of action, or perhaps more grip related training similar to that shown on the Judo-Sport blog recently (via www.planetjudo.com).

Dave has kindly provided me with his data and I shall be looking at it in more detail and will post a follow up in a future article.

A quick test of notation reliability.

I am, as some are aware, presently researching the attack rates of athletes in the 2008 Olympic Judo tournament in Beijing. To do this I am notating the attacks made by each athlete and analyzing the results. As with many forms of analysis there are issues to be addressed around the calidity of the data. One of which is how accurate your recording is, in this post I would like to invite you to help my project by notating a short video from YouTube and emailing me your result, this will be helpful so I can see what the variations in the data are. I shall post the findings of this experiment afterwards.

Notation Methodology:

Take a sheet of paper, draw a line down the middle of the page and notate as follows:

On the paper based hand notation form each attack will be recorded as a vertical line “|” if the
opponent does not touch the floor with another part of the body other than the feet. A “+” will be
recorded if the attack does cause the opponent to touch the floor with another part of their body but
no score is given. The form has two columns, one for each player, the “|” is placed in the
appropriate column for each player. If a score was given, no “|” is marked,  a letter indicating the
score is written instead. These are K for Koka,  Y for Yuko, W for Wazari, I for Ippon and P for a
penalty. When Matte was called, the recorder moves down one line on the notation form. If no
attack has been made a horizontal line is recorded “-”, is neither player has attacked, then both
columns have a “-” recorded. Each period between the referee’s “Hajime” call and “Matte” call is
termed a segment and recorded on a separate line on the form.

If you could forward your notation to me (lw@judocoach.com) that would be terrific, it will be interesting to see how many people participate and also how much the data varys between people. I shall keep your data anonymous of course.

Many Thanks,

Lance.

Ages of medalists at 2009 Judo World Cup events.

Airborn combatIn this post we shall briefly look at the ages of the Judoka competing at the latest Judo World Cup events in Europe. The two events are the 2009 – World Cup – Prague, and the World Cup Warsaw – 2009. Prague was a womens event, Warsaw a mens event.

Method:

  • Ages and results were obtained from the JudoInside website for both events.
  • Data was analyzed for medalists only
  • Statistics between winners and silver and bronze medalists is compared.

Results:

  • 24.95    Average Age of medalist
  • 34    Max oldest medalist
  • 17    Min youngest medalist

Winners/Gold Medalist:

  • FEMALE:  Average age: 25.14(+-5.67)    Max: 34    Min: 19
  • MALE: Average age: 26.2(+-4.66)    Max: 32    Min: 21

Non-Winners/Silver and Bronze:

  • FEMALE: Average age: 25.15(+-3.62) Max: 31 Min: 17
  • MALE: Average age: 24.4(+-3.62) Max: 33    Min: 20

Discusssion:

The sample size for here is very small, a mere 52 data points (of a possible 56).The analysis is in no way comprehensive.

Target age of players to compete in these events:
The ideal target age to be ready to compete in these events is between  19.47 and 30.81 for women and 21.54 and 30.86 for men. How this relates to the 2012 games is a matter of debate, but these target ages suggest either that athletes winning in London will be approximately 28, or that the older athletes competing today will be retired by London 2012, thereby keeping average ages down.

The age span is quite large 17-34, with average winners age being 25-26 years of age. This perhaps indicates younger athltetes need to spend several years at this level before winning. This could be tested by a further examination of ages for those who did not make the medals potentially.

Talent ID:
For countries looking for players to medal at London 2012 this brief analysis could suggest that they need to be focusing on players who are presently around 22 years of age. For the next Olympic games in 2016 a further talent squad could/should be identified who are approximately 18 years old. This could be extended to 2020, 14 years old now.

Statistical Summary of Judo at 2006 Commonwealth Judo Tournament.

The text below is the result of the pilot study that was the inspiration for my BSC. research project at University of Bath on the Beijing Olympic games Judo event. The study looks at the attack rate of players in the 2006 Commonwealth Judo tournament and their success rate. I have posted it previously on www.judocoach.com/judo but have decided to add it here as it is in keeping with the subject of this site.

Summary of the 2006 Commonwealth Judo Tournament.

Introduction:
At the 2006 Commonwealth Tournament, a study of the attacks,
scores and durations of bouts was made. Eighty-nine bouts were successfully notated. The results
have been collated and analysed and this document is a summary of the findings.
Full details on the study and methodology are being developed so to make them available to
everyone. The hope is that this will encourage others to conduct similar studies.
Statistics:
Descriptive Statistics
Total Fights 89
Total Scores 139(no penalties)
Total Attacks 1305
Total Penalties 100
Total Segments 732
Total Match Time 259Minutes 101.45Recovery time in fights
Total Actual Time 360Minutes 1.14Recovery per fight
Total Possible Contest Time 432Minutes 0.14Between segments
Fights won by Blue 47 53%
Fights won by White 42 47%
Fights won by person who attacks most 61 69%
Fights won by person who attacks least 28 31%
69 33%
21 10%
61 29%
58 28%
Total: 209
Scores per fight (AVG) 1.56
Attacks per fight (AVG) 14.66
Penalties per fight (AVG) 1.12
Segments per fight(AVG) 8.22
Of Actual time on mat 72%
Of time allocated 83%
Scores per segment 0.19
Attacks per segment 1.78
Penalties per segment 0.14
Ippons Scored
Wazaris Scored
Yokus Scored
Kokas scored
(incl Penalties)
Findings for players and coaches:
By averaging out the results of the data collected, we are able to describe an average Judo bout at
the Commonwealth Tournament level.  An average fight at commonwealth level consists of the
following:
Each match is approximately four minutes long, and consists of eight “segments” of action.
Each segment of approximately 30 seconds in duration, with 14 seconds between each segment.
Within each segment we can expect 1-2 attacks only before Matte is called.
We can expect a score every 7-8 segments, this score will be Ippon 1/3rd of the time. The other
two thirds of the time it will be divided almost equally between Koka & Yoku. Wazari will be
scored infrequently (only 10% of the overall scores).
Given this description of an average match, we are able to develop coaching strategies and
training sessions to best simulate commonwealth level Judo. Sessions could be developed
following approximately the following format.
Endurance drill:
Athlete attacks at near maximal level for 30 seconds.
They then recover for 14 seconds
The above two steps are repeated 8 times.
This drill helps develop the athletes ability to give maximum effort for entire match for difficult
matches.
Tactical Drill:
Athlete fights for grip for 10 seconds
Coach calls “NOW”, and athlete must make one large attack
Athlete then continues to grip fight for 10 seconds
Coach calls “NOW”, and athlete must make one large attack
Athlete recovers for 14 seconds
Repeat above steps eight times.
This drill trains the athlete to make maximum use of the available time. Minimising risk of
passivity attacks whilst keeping energy expenditure minimal.
Active defence Drill:
Athlete is attacked constantly for 30 seconds, they must only defend.
At 10 seconds the coach shouts “NOW”, the athlete must make some form of positive attack.
At 20 seconds the coach shouts “NOW”, the athlete must make some form of positive attack.
At 30 seconds the coach shouts “NOW”, the athlete must make some form of positive attack, this
attack must be “terminal”, concluding on the floor or outside safety area.
Recover for 14 seconds
Repeat above steps eight times.
Summary
This document is a very basic analysis of a small amount of information from the 2006
Commonwealth Tournament. It is hoped that this documents shows how this form of study and
analysis can provide interesting insights which can be applied to training programme
development.
Further analysis of the data is under way and a more detailed document will follow.
The use of simple mean averages provides generalised information which provides only an
indication of general trends in the data analysed. This needs to be considered when developing
training programmes.
For example, the four minute figure mentioned in this document is a mean average of all the
fights recorded. The range of durations went from a few seconds to over twelve minutes spent on
the mat.
Similarly, the mean averaged number of segments, covers all stages in a competition. Initial
examination of the data showed a visible change in contest structure in the later stages of a
category. This included more segments, hence more attacks, but with each segment being sorter.
Your athlete may be better served by drills that followed this pattern over the average format of a
Commonwealth level Judo match
Full details of this research are available via the www.JudoCoach.com
website and/or by contact the author, Lance Wicks, directly at the email
address: lw@judocoach.com. Fellow researchers are invited to contact Lance
Wicks to source the data and digital copies of the notation forms, etc.
It is hoped that this research will act as a catalyst, encouraging further
research within the sport by researchers both with and without experience.
Kia Kaha, Kia Toa, Kia Manawanui
Be brave, Be Strong, Be Perservering
(Old New Zealand Maori Saying)
(c)2006, Lance Wicks. www.judocoach.com lw@judocoach.com

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