Carlsen - Nepo Game 10

 Carlsen kept his 3-game lead

Carlsen - Nepo Game 9

 Carlsen wins again and now leads by 6-3.

Carlsen - Nepo Game 8

 Carlsen won again and took a 5-3 lead. Nepo needs a miracle.

Carlsen - Nepo Game 7

 Nepo failed to strike back with the white pieces, so his chances continue to fall.

Carlsen - Nepo Game 6

Carlsen won Game 6 and leads 3.5-2.5. Since he is ahead and has the higher rating, the model says he is heavily favored to win. 

Carlsen - Nepo Game 5

 Another draw. Not much changes in the forecast.

Carlsen - Nepo Game 4

Another draw, so now the score is 2-2. Carlsen's chances continue to fall. When Carlsen draws with black, there is little change. White has a slight advantage, but Carlsen is the stronger player, so it roughly balances out. But when Carlsen is white, the model has higher expectations of him - he has the advantage of the first move and he is the better player, so a draw is a disappointment.

Carlsen - Nepo Game 3

 Another draw. Not much changes in the forecast:

Carlsen - Nepo Game 2

 Nepo held a draw with Black, so his chances improved a bit. The forecast with the new model:

Carlsen - Nepo Game 1

Carlsen drew with black, and the new model's forecast barely changes:

Carlsen wins: 81.45%

Nepo wins: 8.9375%

Match drawn: 9.6125%

Carlsen vs. Nepomniachtchi 2021 - and a new statistical model!

The match will be 14 games instead of 12. This is an improvement. In longer matches, there is a better chance that the stronger player wins (see my articles in ChessBase and Chess Life for more information). However, it is still too short. In "Reforming the Candidates Cycle," I ran simulations and recommended 24-game matches.

Carlsen's rating is 73 points higher. This gives him a big edge. The forecast from the traditional model:

Carlsen wins: 82.86%

Nepomniachtchi wins: 9.115%

Match Drawn: 8.025%

However, the traditional model is due for an update. Sometimes it assumes a draw rate that is too low. I had taken games from my database and plugged them into a statistical model (see the methodology section for more details). However, most of the games didn't come from elite tournaments. A battle between 2400s doesn't tell us much about what will happen in the world championship. The model did correct for the ratings and acknowledged that stronger players draw more often. However, the adjustment wasn't fully satisfactory. It expects the draw rate between Carlsen and Nepo to be just 50.1569%! We could get more decisive games in this championship than in the last three combined!

Now for the paragraph that most readers will want to skip. I built a new model using games where both players were 2700+. Rapid, blitz, and online games were dropped. An ordered logit estimated the probabilities of win, loss, or draw. The independent variables were a second degree polynomial of white's rating, black's rating, and year (higher order terms were insignificant). Then I compared the model's draw rate to the actual draw rate in a subsample: both players 2750+. In this group of about 4000 games, the model expected 57.4% of them to be drawn; the actual draw rate was 58.4%. Not bad. Earlier I tried a larger database with both players 2600+ or 2500+, but in those samples, the predicted draw rate for 2750+ was too low. I tried various ways to put more weight on games with stronger players, but the predicted draw rate barely budged. The other main difference is that the traditional model uses the expected score formula to generate the probabilities of a win or loss. The new model uses the ordered logit to obtain these probabilities.

At the end of the day, the new model's predictions are quite similar:

Carlsen wins: 81.34%

Nepomniachtchi wins: 9.395%

Match Drawn: 9.265%

I will be updating the new model's forecast after each game

2021 National Memory Championship: The Final

Those who qualified back in August were joined by two former champions, Nelson Dellis and John Graham. Four elimination events would whittle down the field from 11 finalists to one winner. I felt more pressure this time. Back in 2018 and 2019, I barely qualified, so I didn't expect much of myself in the final. But in this year's qualifier, I won the Memory League section and got 3rd place overall. I was supposed to do well. The date of the championship - October 23 - loomed over me for weeks. But somehow I was calm on the night before. I slept reasonably well without any medication.

The opening event was Pinball Recall, a game from Lumosity. The bumpers appeared on the screen for about a second and then vanished. We had to remember where they were in order to predict where the ball would go. It looks simple in the tutorial, but when there are 8 bumpers spread out over a 5x5 grid, it gets tough.

The finalist with the highest score got to choose their seat. Whoever finished #2 got the second choice, etc. For example, if you pick the 11th seat, you will get asked the 11th question when you are on stage. This could be advantageous; if the round ends in the middle, then those at the beginning had to answer an extra question. I barely trained for this. The other events were more important. I screwed up the very first one. I pulled myself together and made it up to level 12. But it wasn't enough. I was next to last and ended up in the second seat.

The first event was "Words to Remember." We had 15 minutes to memorize up to 300 words. Two mistakes and you are out. The round would continue until 2 finalists were eliminated. I had been training on Memory League, where you have just 1 minute. About a week before the event, I realized that my results over there might not translate into a strong performance at the championship. Having 15 minutes to memorize is very different from having 1 minute. In training, I tried slowing down a lot and emphasizing accuracy. I figured that it wouldn't be too hard to outlast the 2 weakest competitors, but I didn't want to get complacent. What if I fly all the way to Orlando and get knocked out in the very first round? I was a bit jittery while memorizing and aimed for about 110 words. In the past, 100 had always been enough. Exception: 2019, where I got eliminated since I only knew the first 100. Everything started smoothly enough. A high schooler was eliminated quickly. Then we got to the 49th word. I thought it was "insult" and was shocked to get it wrong. The next finalist had to correct my mistake, but he also stumbled. He said "insulate." Makenna Good (last year's champion) also thought it was "insulate" and was eliminated since it was her 2nd mistake. The event ended and the 9 remaining finalists advanced. It turned out that the word was "insulted." It sounds like a minor mistake, but missing that is inexcusable for me. I went really slowly and reviewed multiple times. I have a system for common prefixes and suffixes; if a word ends in "-ed," I should add a graduation cap to the image in my memory palace. I had gotten sloppy about that. I was off to a shaky start, but I was still in contention.

The next event was long term recall. A month earlier, we were given a list of Pulitzer prize winners, US Winter Olympic gold medalists, and the periodic table of elements. About 2500 bits of information in all. Memorizing it was a tremendous amount of work. I finished about a week before the championship, but I still had to review it at least once a day. Each review took more than an hour. It exhausted my supply of memory palaces, so I also spent hours finding new ones and learning them. I hate this event. But all the work paid off, and I sailed through comfortably. This was the first time that I had ever made it past round 2. James Cumming, who had won the qualifier in August, was eliminated. Rishabh Kasarla (a pre-med student) and Kaitlyn Wei (high schooler and daughter of a former competitor) were also knocked out.

Round 3 was the Tea Party. We would watch videos where 4 "tea party guests" would introduce themselves. We would have to memorize their names, birthdays, phone numbers, occupations, and much more. In training, I was doing well, but by now the weakest finalists had been eliminated. I wasn't sure if I could outlast the best. Three strikes and you are out. The first video started playing, but the audio was very hard to understand. I only caught a few pieces of information. In the next videos, the quality didn't improve. This was going to be a disaster. About midway through, I had a realization. The other competitors were probably struggling just as much as I was. So as long as I get just 1 or 2 questions right, I might prevail. I focused on the first pieces of information: name, birthday, home town, and education. By now I was in the first seat - I had started 2nd, but the finalist ahead of me had been eliminated. So I knew that I would get the first question, and the first question was going to be, "what is this person's name?" In the last 5 minutes, we got to study the information on a sheet of paper, and I gave extra emphasis to the names. The five minutes raced by. The host pulled up the picture of the fourth guest and asked me what his name was. I was ready. But they accidentally revealed the name. So they moved on to the next question, "what is his birthday?" This derailed me. I had memorized the birthdays, but I thought for sure I was going to be asked about names. I had to answer in 15 seconds, and I couldn't adjust that quickly. Strike one. The rest of the field was also struggling. I failed to recover and was swiftly eliminated. Former champ John Graham was also knocked out, along with Michael Friedman. It was so tough that if I had only gotten 1 question right, I almost surely would have advanced. And I should have nailed the first question, but the name was accidentally shown. A painful way to go down.

Four time champion Nelson Dellis advanced to the final. He was joined by Kyle Matschke and Grace Smith; both of them were former finalists. The last event was memorizing 2 decks of cards in 5 minutes. Nelson was the big favorite and he went on to win his 5th title. Congrats Nelson!

2021 US Chess Championship

The field is very strong, even without Nakamura. We have five members from the 2700 club:

Norway Chess 2021

 The 6-player double round robin features Magnus Carlsen and Ian Nepomniachtchi

EDIT: This applies to the classical games only. I do not have a forecast for the Armageddon. 

2021 US Memory Championship - Qualifying Round

My memory had never been better. But there was a new format, so I wasn’t sure if I would qualify for the finals. Traditionally, there were 4 disciplines: names, poetry, numbers, and cards. I would survive the first 3 and then run up the score in cards. But this year, cards was dropped. Poetry was replaced with images, and then there were 2 new events from Lumosity. I’m terrible at images and I had very little experience with the Lumosity games. So I didn’t assume that I would make it to the finals – no booking my ticket to Orlando yet. The qualifier would be online, but the final would be face-to-face in October.

 

About a month before the qualifier, I started training for the Lumosity games. The first one is Memory Match Overdrive. You flip through cards with different shapes on them. For each card, you have to remember if it matches the one 3 cards before it. I quickly realized that doing it “properly” with memory palaces was just too slow. But without those techniques, my memory is nothing special. I also had no idea what was considered a good score in that game.

 

The other Lumosity game was Rotation Matrix. It starts with a blank grid. Then some squares briefly light up. The grid is rotated either left or right. Then you have to reconstruct the pattern and rotate it accordingly. The squares light up for only a second, so I didn’t have enough time to apply the memory techniques. I just tried to recognize different shapes and patterns. I figured that some Lumosity enthusiast who had been playing these games for years would probably crush me.

 

Each of the 3 main memory organizations has a different format for images. I always focused on the other events that they have in common. One month of training in images is not enough to catch up. Tournaments that count toward the world rankings use International Names, not regular English names. I have done much more training for International Names, so my results for English names had never been outstanding. Numbers was the only discipline that I was confident about. I had spent 2020 upgrading my approach, memorizing numbers in groups of 3 instead of 2. This is more efficient, but making the switch is a tremendous amount of work. But by 2021 it was paying off and I was shattering my old records. The plan was to avoid embarrassment in everything else and then excel in numbers.

 

As the training progressed, my confidence inched up. My Lumosity scores were improving and I broke a bunch of personal records in names and images. But I still didn’t know how my Lumosity scores compared to everyone else. I did know that my results in names and images weren’t world class (to put it mildly). But only a few people in the country can memorize an 80-digit number in 40 seconds. I had a shot.

 

August 7 was the big day. I started with some warmup exercises in numbers. The online tournament started in the afternoon, which is when my energy tends to dip. So I also did a bit of weightlifting in the morning. Not a full workout – I figured I had enough nervous energy to make up for the rest. Then lunch and followed by the pre-tournament Zoom meeting. There were supposed to be 100 competitors, but only about 30 were at the meeting. Maybe the rest skipped it. Maybe they dropped out of the tournament. I didn’t know. I didn’t worry about it. The Lumosity games would be the first two events. We had 15 minutes to play Rotation Matrix and 10 minutes for Memory Match Overdrive. We could play the games multiple times. Only the best score would count.

 

I started with Rotation Matrix. My first score was modest. But it didn’t bother me since I still had plenty of time to repeat the game. On the next trial, I broke my personal record, scoring 28,050 points. I briefly wondered if I should quit and move on to the next game. But only the top score counts, so if I keep playing, my score cannot go down. After a few more modest results, I broke my record again right after my time expired. I took a short break before Memory Match Overdrive. Again I didn’t get a great start. But soon I scored about 32,000, just shy of my record. I was doing exactly what I needed to do: hit my targets in Lumosity so I was still in the running if I did well in everything else. Later it was announced that the top scores in Lumosity were 69,400 for Rotation Matrix and 56,600 for Memory Match Overdrive. But I didn’t know that at the time and thought I was having a good day.

 

We reconvened for the Zoom meeting. Attendance was still low. I was starting to think that a lot of people had registered and then decided not to play. Many of the big stars weren’t there. The top 10-12 advance to the final, so if they aren’t taking up those spots, the rest of us have more of a chance. The Memory League games were modified for this tournament. Instead of having a maximum of 1 minute, we had up to 5 minutes. They stressed that accuracy trumps speed. There is a bonus for finishing in under 5 minutes, but only if you are perfectly accurate. There were 2 trials for each event. Only the higher score counts. I didn’t know the formula for the time bonus. I thought about asking but decided not to. I didn’t want to be mentally calculating my score and wondering how that stacked up against everyone else. Just focus on getting stuff right.

 

Images came first. We had a sequence of 30 pictures to memorize. Then they were scrambled and we had to put them back in the proper order. Since accuracy was so important, I decided to go slowly and then review everything once. This took 55 seconds – a very slow time, but I got it all right. In the second trial, I went for speed and skipped review. I was done in 38 seconds. This is still a very slow time, but for me it was almost a personal record. Unfortunately, I made a few mistakes. Nevertheless, I had no regrets. Even a beginner can get a perfect 30 if you give them 5 whole minutes, and accuracy is more important than speed, so I needed to get at least 1 perfect score. Having secured that, I could focus on speed and my score can’t go down since only the top one counts. I just needed to avoid disaster in my weakest event – and I did.

 

Names. I had never done it in this format before – 5 minutes for 30 names, with 100% accuracy required to get a bonus. Again, I started by playing safe. Go slowly and review everything once. About 2 minutes later, I stopped the clock. Everything was clear and I got a perfect score. For the second trial, I decided to go faster. But I was caught off guard by a few names that I hadn’t seen in training, like “Daryl.” We try to make everything visual and put it in a memory palace, but some names are harder to visualize than others. For example, “Ross” is easy (think of floss) and so is “Sam” (ham). But what do I do for “Daryl”? I decided to go with pterodactyl. A few names like that slowed me down and although I got another perfect score, my time was worse than in the first trial. But I was still happy with my performance so far. I had gotten through all my weakest areas. Now I could flex in the last event: numbers.

 

Safety first. I took 65 seconds to memorize the 80-digit number and review it once. I easily got a perfect score. In the second trial, I skipped review. But I was unable to turn on the speed. It took almost 47 seconds to finish. Normally I am in the 35-40 second range. But it was still good enough to take the top score. I knew I was nearly guaranteed to make the finals.

 

We had a short break while the organizers tallied up the scores. I took 3^rd place! My best result ever. Though I was 12^th in the Lumosity events, finishing 1^st in Memory League was more than enough compensation. I was so relieved. It felt like I had been carrying a burden for the last several weeks, and now it had been lifted from my shoulders. I enjoyed an extra long piano practice session and the next day I celebrated with family. In the finals, I will be facing a relatively weak field and have a real chance at winning. This could be my year!!

Memory League Scores

Scores from all events

Superbet Chess Classic

 This 10-player round robin is part of the Grand Chess Tour - over the board chess is back!

EDIT: Original post mistakenly had Rapport in the tournament and left out Deac. That has been fixed.

Candidates 2021

 The 2020 Candidates Tournament was postponed; the second half begins this month. Nepo and MVL were leading with 4.5/7, but in the forecast, Nepo is the favorite. That is because MVL shed 26 rating points in the 2021 Tata Steel Masters. Caruana trails at 3.5/7, but the model still thinks he has a chance due to his high rating. 

K+Q vs. K+R: One more key position to know

 A few months ago, I posted an article about queen vs. rook. I have one position to add to it. 

[Event "?"] [Site "?"] [Date "????.??.??"] [Round "?"] [White "New game"] [Black "?"] [Result "*"] [SetUp "1"] [FEN "8/8/8/8/1K6/8/rk6/3Q4 w - - 0 1"] [PlyCount "5"] {If it is Black to move, then it's zugzwang. If it is White's turn, then the best move is} 1. Qd5 $1 ({Not} 1. Qb3+ Ka1 2. Kc3 $4 Rc2+ $1 3. Kd3 Rd2+ $1) ( 1. Qd2+ Kb1 2. Qe1+ {hopes for} Kb2 3. Qd1 { zugzwang, but Black can avoid this with 2...Kc2}) 1... Kb1 2. Kb3 Rb2+ 3. Ka3 { and the rest is straightforward} *

Converting Q vs. R was critical to becoming the #1 endgame benchmark player on ChessTempo

Tata Steel Forecast

 We are back to forecasting chess tournaments!! The model was designed for classical games, so I could not use it for all the online rapid tournaments that we saw over the last year. World Champion Magnus Carlsen is the top seed in the 14-player round robin.