Today we're pleased to announce the release of the second volume in Grandmaster Richard Pask's projected five-volume Logical Checkers series. Volume 2 is entitled Freestyle Expert.

Following on the heels of the highly successful first volume, Checkers for the Novice, the new book delves deeply into tactics, endgames and mid-game formations as well as landings and various freestyle (go-as-you-please) openings.

You can get the new book in its first electronic edition from the Richard Pask page as linked in the right column, or directly here. Through Mr. Pask's generosity the book is provided completely free of charge. The book runs to about 180 pages with over 150 diagrams and numerous illustrative games.

To demonstrate one small part of the content of this wonderful new book, here's the run-up to a sample tactics situation.

11-16 24-19 7-11 22-18 3-7 25-22; 10-14??---A 22-17 7-10 17-13 16-20---B, to the diagram.

A---Mr. Pask here quotes Richard Fortman: "This radical departure might be classified as a 'coffee-house' move, but impractical against a former world champion!”

B---2-7 29-25 16-20 25-22 14-17 21x14 10x17 19-15 12-16 28-24 17-21 24-19 8-12 15x8 4x11 19-15 7-10 15x8 White Wins---Ed., with KingsRow.

To see the solution, simply download the new book and turn to page 123. Our thanks as always to Mr. Pask for according us the privilege of editing and publishing his work.

Fred C. Shardlow, born in New York around 1874 and subsequently a resident of the Marshall, Minnesota area, was a song composer, and is credited with the song, For the Love of Thee for voice and violin.

Mr. Shardlow was also a checker problem composer, and we feature one of his "Gem" problems in today's Checker School entry. Unfortunately we don't have further information about his checker career, although we did locate some other problems of his published in the American Checker Monthly and the Winnipeg Free Press.

So, for the Love of Checkers, take a look at the following position.

We know you would love to solve it, so please do! And when you're done, you'll love to click your mouse on Read More to verify your solution.

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Who wants to start off the New Year in a dull and boring manner? The waterfall jumper above is certainly looking to make this day anything but routine.

And while we can't recommend waterfall jumping for everyone, the same principle applies to checkers. How about we start off 2019 with a real bang, courtesy of regular contributors Lloyd and Josh Gordon of Toronto?

Black seems to have only one mobile piece. Can he truly pull out a draw?

This may be just a little past the 30 second "speed problem" category, but it's not terribly difficult and it certainly is loaded with action.

Kick off your checker year with some real thrills. Solve the problem and then jump your mouse onto Read More to check your solution.

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This column will appear a few days before the New Year of 2019, and no doubt you're busy with all sorts of preparations. Are you going dancing? Taking a dinner cruise? Watching fireworks at a nearby location? Or just staying home for a celebration with friends, or even a quiet evening?

There are as many ways to celebrate as there are people, and given how busy most of us seem to be, today we have a "midget" checker problem that won't take up a lot of your time, while still being worth a little effort.

Finish off your checker year by finding the solution, and then get back to your celebrations. There will be plenty more checkers in 2019! When you've finished, click on Read More to check your moves.

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The story of the Three Kings is a central part of Christian celebration of the holiday of Christmas. Also known as the Three Magi or the Three Wise Men, and sometimes identified as Balthasar of Arabia, Melchior of Persia, and Gaspar of India, they traveled to Bethlehem with their gifts of gold, frankincense, and myrrh, each of which is said to have a symbolic meaning. And whether you celebrate Christmas or some other holiday, the Three Kings make for a fascinating and meaningful story.

We hope you'll have a little time for checkers during the busy holiday season, and in our archives we found a "Three Kings" checker problem. We lost track of the author's name, but nevertheless the problem is very fitting--- and a bit on the difficult side.

Were you able to solve it? The first move, as is often the case, is the key. We hope you gave it a good try; whenever you wish, you can click on Read More to see the solution.

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Tommy Wagner had, with the help of Uncle Ben (a retired checkers master who wasn't really Tommy's uncle, even though it seemed like it), worked through his disappointment at not making the Varsity Checker Team when he started high school a little earlier this year. Although Tommy was a Class A player, he wasn't yet ready to complete with the experts and the titled master who made up the Varsity.

But Tommy had easily made the Junior Varsity, and, in competition with no less than three other Class A players, had won the role of Junior Varsity Captain. Uncle Ben, who tutored Tommy most Saturday mornings, told Tommy he was very proud of him.

"But you've got your J.V. home opener coming up on Thursday night against Jacksonville Central," Uncle Ben reminded him.

It was indeed a Saturday morning and Tommy was sitting on Uncle Ben's porch, sipping from a glass of Uncle Ben's famous lemonade.

"Yes, Uncle Ben, and I hear they're pretty tough."

"Scouting reports say they have an Expert ranked player on their top board. That's going to be a challenge."

"I'm not afraid, Uncle Ben. I'll give it everything I've got, and I won't let her scare me."

"Leticia Wong is said to be a rising star." Uncle Ben didn't add that the scouting reports said the same about Tommy.

"Hopefully, she'll bring out the best in me," Tommy said.

"Very well, then, let's get to practicing."

Tommy and Uncle Ben practiced longer and harder than usual that Saturday, and Tommy worked hard during the coming week, too. But Thursday rolled around pretty quickly, and on that evening, Tommy found that Leticia was indeed a formidable opponent.

There was a big crowd in the stands. Out on the field, under the lights, the score was tied at 2-2, and Tommy and Leticia's game would decide the match. Tommy really wanted to bring in a win for the home team, and he had White in the following position.

It was Tommy's move. He knew he could get a draw, but his team needed a win. The clock was ticking and Tommy was low on time. He had to decide quickly.

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Are you a rising star like Tommy or Letitia? Your standing doesn't matter; solving the problem will be a good exercise. Give it your all--- your team is depending upon you--- and then click on Read More for the conclusion of our story, and no less than 14 examples of the theme, including the problem solution.

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The American Checkerist was a print publication edited for many years by the prolific and talented William Ryan, who stands with Ben Boland and others among the famed golden age authors of books about checkers. Willie had a great command of the English language and wrote with a style and flair all his own.

In today's Checker School column, we have another "gem" problem, this one by William V. Scott and originally published in The American Checkerist.

Wow, what's this? Five pieces per side but White has three kings to Black's one, Black is underdeveloped, and yet Black is supposed to win it? We'd almost call this a "Coffee and Cake" problem, but a closer look shows that Black has some definite positional advantages, and the problem is actually "medium" in difficulty.

Can you make this into a Black win? You don't have to be an "American Checkerist" to solve it. Find the winning line of play and then click on Read More to see the solution. Then, see if you can answer this: the 35 cent magazine in the photo above--- what would that amount to in today's money?

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This weekend The Checker Maven completes an unbelievable 14 years of continuous publication with never a missed deadline. Week after week we've brought you something about checkers, and from what you've told us, you've seemed to enjoy it.

Originally we were going to publish for 10 years. We upped that to 15 and called that a "hard" limit. That leaves us one year to go. But we turned to Mr. Bill Salot for inspiration; he's in his eighties, going strong in every possible way, and makes no excuses about age or health as he continues to support our game of checkers.

So we're going to continue publication. There's no saying how long that will be--- your editor has serious eyesight issues, for one thing--- but we won't quit as long as we can physically continue.

It seems only fitting to celebrate this anniversary and this announcement by going back to our origins, with a "Coffee and Cake" problem from Brian Hinkle. Recall that a "Coffee and Cake" problem is one that you show to your checker friends and bet them coffee and cake that they can't solve it. Brian calls this one "Trumped" (no political reference intended).

Stay the course. Don't make excuses. Carry on. We wouldn't call this an easy problem, but--- like publishing The Checker Maven every week--- your efforts will be well rewarded. When you've found the right moves, click on Read More to check your solution.

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It's another year with five Thursdays in November, so Thanksgiving in the United States comes well before the end of the month, on November 22. This column will first appear during Thanksgiving weekend.

We've always said how much we love Thanksgiving; its appeal to everyone of every faith and background makes it truly American in spirit. We hope you are enjoying the weekend in whatever way pleases you most, whether it's a large family gathering, a small intimate group, or just some days off to relax. But do remember to be thankful for what you have. While we may not have everything we want, we always have a lot more than we think.

Make checkers part of your weekend with a Tom Wiswell problem, one that he calls "The Follow Through." In his description Mr. Wiswell notes that sometimes a player will give up on a problem just a move or two short of finding the key move. In today's study, staying the course will get you there.

White is a man up but is about to lose it back. How can he win?

Take a break from turkey sandwiches and pumpkin pie, and follow through to the solution. Then let your mouse follow a path to Read More to see how it's done.

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Computers have progressed a very, very long way since their earliest days. It may not be quite as well known, though, that computers have been programmed to play games since almost the very beginning. But we doubt that the hardy coding pioneers of the time would have dreamed just how far the state of the art has come since then.

Certainly well known today are Google's phenomenal Alpha game playing programs, which contain self-teaching or "machine learning" methods. After years and years of computer Go programs barely reaching respectable playing levels, AlphaGo appeared on the scene and defeated one of the world's highest ranked Go players, something no one ever expected. And AlphaChess very quickly became able to defeat even the strongest chess playing programs around. Machine learning is here to stay, and the results are phenomenal.

Of course, it's not new. The idea was proposed by an IBM scientist over 60 years ago. But implementing it successfully was the issue, for to succeed, the computer programs would have to "train" on millions and millions of different game positions. That wasn't a realistic possibility until relatively recent years.

The method worked well at first for non-deterministic games--- games with an element of luck. Gnu Backgammon played at the master level, as did others. But applications to checkers largely failed. Blondie 24 was a lot of fun but never a serious competitor, and NeuroDraughts wasn't fully developed.

All that has changed, though, with renowned checker engine programmer Ed Gilbert's latest developments for his world class Kingsrow computer engine. Ed was kind enough to send us the details. The following was written by Ed Gilbert with input from Rein Halbersma.

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The latest Kingsrow for 8x8 checkers is a big departure from previous versions.

Until recently, Kingsrow used a manually built and tuned evaluation function. This function computes a numeric score for a game position based on a number of material and positional features. It looks at the number of men and kings of each color, and position attributes including back rank formation, center control, tempo, left-right balance, runaways (men that have an open path to crowning), locks, bridges, tailhooks, king mobility, dog-holes, and several others. Creating this function requires some knowledge of checkers strategy, and is very time consuming.

The latest Kingsrow has done away with these manually constructed and tuned evaluation features. Instead it is built using machine learning (ML) techniques which require no game specific knowledge other than the basic rules of the game. It has learned to play at a level significantly stronger than previous versions entirely through self-play games.

In a test match of 16,000 blitz games (11-man ballot, 0.3 seconds per move), it scored a +72 ELO advantage over the best manually built and tuned eval version. There were more than 5 times as many wins for the ML Kingsrow as losses.

The ML eval uses a set of overlapping rectangular board regions. These regions are either 8 or 12 squares, depending on whether kings are present. For every configuration of pieces on these squares, a score is assigned by the machine learning process. A position evaluation is then simply the sum of the scores of each region, plus something for any material differences in men and kings. In the 8-square regions, each square can either be empty or occupied by one of the four piece types, so there are total of 5^8 = 390,625 configurations. In the 12-square regions there are no kings, so there are 3^12 = 531,441 configurations.

To compute values for each configuration, a large number of training positions are needed. I created a database of approximately one million games through rapid self-play. Each game took about 5 seconds. The positions are extracted from the games, and each position is assigned the win, draw, or loss value of the game result. Initially the values in the rectangular board regions are assigned random values. Through a process called logistic regression, the values are adjusted to minimize the mean squared error when comparing the eval output of each training position to the win, draw, or loss value that was assigned from the game results.

Similar machine learning techniques have been used in other board game programs. In 1997, Michael Buro described a similar process that he used to build the evaluation function for his Othello program named Logistello. In 2015, Fabien Letouzey created a strong 10x10 international draughts program named Scan using an ML eval, and around this time Michel Grimminck was using a ML eval in his program Dragon. Since then other 10x10 programs have switched to ML evals, including Kingsrow, and Maximus by Jan-Jaap van Horssen. I think that the English and Italian variants of Kingsrow are the first 8x8 programs to use an ML eval.

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Ed's new super-strong version of KingsRow is available for free download from his website. Combine that with his 10-piece endgame database, and you'll have by far the strongest checker engine in the world, a fearsome competitor and an incredible training partner.

Let's look at a few difficult positions, some of which were analyzed by human players for years and even by reasonably strong computer engines for hours. KingsRow ML solved each and every one of them virtually instantly.

First, the so-called "100 years problem" (as in Boland's Masterpiece, p. 125 diagram 1).

Next, the Phantom Fox Den, from Basic Checkers 2010, p. 260.

And finally, a position suggested by Richard Pask, from Complete Checkers p. 273 halfway down, where Mr. Pask notes: "12-16?! has shock value ..."

Surely we don't expect you to solve each of these (unless you wish to), but do look them over and at least form an opinion. Then click on Read More and be amazed.

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