http://sugarroad.blogspot.jp/2012/07/puzzle-030-dutch-loop-lmi-prac... There's a practice puzzle out there for one of the slightly rarer loop variants on the test.

Hello players,

I have some small notes concerning the test, which I want to tell you

1. In Border loop, every pentomino must be formed by exactly 5 dots
2. The PB will be without examples

And if you have any questions, only ask and I will try to answer them :)

I agree with Rakesh. I think many players would 'naturally' enter answer keys in the 'loop segments' format, especially during the tense moments of entering answer keys as fast as possible.

The answer keys are certainly unconventional.Areas of cell clusters outside the loop could be a possible workaround, but it is very tedious too ?

Thanks for bringing it up. It indeed helps that we discussed this before the test starts, so that we can take corrective action.

We have decided to accept the alternate answer key for all puzzles. The alternate answer key is "Enter the lengths of longest horizontal segments for the marked rows". If there is no horizontal segments, the length is 0. We have used this in many tests in the past, so everyone should be more familiar with this one.
From the IB puzzles, here are the alternate answer key for some puzzles
Masyu - 204
Slitherlink - 311
Corral - 213
Dutch loop - 414

Puzzle will be marked correct if the original answer key or the alternate answer key is entered. You may even opt to enter different kinda of answer keys for different puzzle. (However, it will help you if you stick to one kind of key).

Hope it helps everyone.

Logirace means what puzzle whether is it sudoku because i am interesting to play sudoku competition championship

LMI hosts one puzzle test and one Sudoku test each month. The list can be found here - http://logicmastersindia.com/forum/forums/thread-view.asp?tid=60&st...

Also, at the topic start above, if you click on the logo, you will go to the test page, where if you download the "Instruction Booklet", you will get all the instructions necessary.

If you still have doubts after checking out the IB, feel free to post them.

Some puzzles of the 5 non-Nikoli genres.

http://puzzleparasite.blogspot.nl/2012/07/lmi-practise-logiraces.ht...

"Your timer will start when you click "Start Logirace" — then you will have 100 minutes (including 10 minutes of extra time) to solve and submit your answers."

I saw this mentioned in the Timing section of the Logirace page. But the Instruction Booklet mentions nothing about extra time. Is there point loss in this extra time?

Edited by Para 2012-07-21 4:52 AM

There is no extra time and all that. It is fixed 100 minutes. The submission page is rectified now.

It looks like organizers are still in Copy-Paste mode

About "Claim No Penalty" button :
For every wrong submission, there is Claim No Penalty button. Following types of claims will be accepted
1) Enter answer for puzzle A is entered into puzzle B's box
2) Getting multiple penalties for same wrong answer.

Very nice puzzles, especially country road and dutch loop !

Edited by prasanna16391 2012-07-21 7:50 PM

[deleted - question about scoring that I've already worked out]

Edited by Gareth 2012-07-21 8:50 PM

Thanks for the interesting contest and many enjoyable puzzles. Also, thanks for using instant grading which I really appreciated trying for the first time (Marathon wasn't exactly a good test since it was really a start/end thing only). I certainly appreciated the comfort of knowing I was done with a page of puzzles, but I was a little sloppy in two cases about checking my work. Then again, I think I've lost more points on dotted snakes/loops for the same reason at WPCs/LMIs than any other "easy" type, so my ability to "check" that puzzle seems to consistently fail.

I'll be interested to hear after the test what new comments people thought about instant grading or the penalty system, as I do want to implement it again in my next LMI test.

Edited by motris 2012-07-23 11:03 PM

Thanks for the loop puzzles. I found both Country Roads and both Corrals particularly nice; honestly they were some of the few puzzles I did with logic in my run. I've gone back and found logical solutions to most of them now, but I've not been able to avoid using uniqueness on the hard Masyu, and I can't get much of anywhere on the hard Comet without a guess (albeit a very educated intuitive one).

With all loop puzzles that even included a tapa variation, and an instant grading system to compensate for my out-of-form checking recently, it would have been harder to give me a better gift from a competitive standpoint...


For my feedback on the instant grading system, there is still the major issue of the penalty not being strict enough. When preparing for the test, I made the decision to have the instant grader do all of the checking for me. That choice probably boosted my score a little, even though I had two wrong submissions. There seem to be multiple reasons for introducing an instant grading system, but I don't think one of them was supposed to be to eliminate the need for checking entirely. That is basically what is happening with every instant grading system used by LMI so far. I did the same thing on Marathon, and I should have done it on motris's test last year.

For this test, if you're sticking with the flat penalty, you probably would have needed to go up to 15 or 20 points per mistake before I'd consider doing my own checking. But this penalty is more than the value of several puzzles on the test which is kind of odd. A possible alternative is to have the same 5 point penalty but also reduce the point value of the goofed puzzle if it is solved correctly later. Maybe a third of the original value for each mistake (meaning the puzzle is worth nothing after the 3rd wrong submission).

Thanks for the loop puzzles. I found both Country Roads and both Corrals particularly nice; honestly they were some of the few puzzles I did with logic in my run. I've gone back and found logical solutions to most of them now, but I've not been able to avoid using uniqueness on the hard Masyu, and I can't get much of anywhere on the hard Comet without a guess (albeit a very educated intuitive one).

Just thought I'd copy it since my feelings are exactly the same, only addition being - I liked the Border Loops a lot too.

About Instant grading, another alternative can be, once someone submits a wrong key, the penalty can keep increasing per minute from that point on till the person re-enters the correct key. This way, if its a typo you can correct immediately and not have much of a penalty, but if its a solving error, you'll have to go back on it and the penalty will be proportionately bigger. At a point where the penalty exceeds the points one can give up the puzzle and move to the next one. If you don't submit the puzzle again after the first time, you get no penalty/a flat low penalty for it.

Logirace is now over. Congratulations to MellowMelon, motris and Para for taking the top 3 positions.

Thanks Matej Uher for authoring the test. May be Matej will share his thoughts on his first LMI contest soon.

Indian top 3 are Prasanna, Rohan and Swaroop.

Out of 223 players, 156 players solved at least one puzzle correctly and 153 ended up with positive scores. Thank you all for participating.

Edited by Organisers 2012-07-24 11:22 AM

I was indeed expecting a TVC like result from you on this contest, so I am glad to have achieved at least a runaway second place, even if still clearly not as fast as first. I'm fortunate to have even found any time this weekend to take the test.

On instant grading: My most recent thinking for the penalty is to have it be high, but give solvers one cheap miss. It probably wouldn't work well on a test like this with a 6 point puzzle, but with something like my two value point system, say 20 or 50 per puzzle, I'd say 5 points for first mistake, then 15 points for each subsequent mistake. I think 15 points (~1.5 minutes of test value) is high enough that I would have checked a bit harder before the second very quick resubmit on a still not fully retweaked Dotted loop. Your comment suggests about the same.

I think the bonus system is good for varied rounds. But I think in these single source or type tests it can cause these runaway performances. Like here with all Loop puzzles, or for example all Nikoli puzzles. Extremely high bonuses can become a bit dangerous. Only 10 people ended up coming within 50% of Palmer's top score, which is a bit over the top.

I like Instant Grading in some sense, mostly to avoid losing points on entry key errors (although I do hate waiting 20 times for the score to turn green, I still dread making a mistake). I would also opt for a 2 value penalty system, but I would opt for differentiating between a typo and a solving error. And I think the cutoff would fit nicely at 60 seconds. So a fix within 60 seconds would be 5 points or 20%(which is what we now use for errors i think) and a fix afterwards would be 15 points or 50%. Of course people should really avoid hitting submit all then.

Edited by Para 2012-07-25 12:07 AM

One of the great things about the instant grading is that if you misunderstand the key you can still get points because you have a chance to realise; but it can take a few minutes, not a few seconds, to re-read the instructions and try to see what you've misunderstood. I can see that at the top level it's possible to somewhat hammer the instant grading for extra speed, but for the average player (which by definition most of us are) this is less significant and I would suggest the advantages to the many should outweigh the disadvantages for the few. Time limits to re-submit would penalise average players even more than better players too, since they would inevitably take longer to fix their errors in any case...

So I would say even if it's not a perfect system for comparing the top players, the fact that it makes the tests much more inviting for the vast majority of other users is a very good reason to stick to something close to the current system. For this to remain true the penalty needs to stay relatively small - this is particularly important to solvers who don't get through many puzzles in a test. And I think time limits would excessively penalise less experienced players (or people like me who get the Masyu key wrong and take 5 minutes to work out why...)

Edited by Gareth 2012-07-25 1:52 AM

Could you please give a little more indication of which tests are ok for you? I don't know what you are excluding when you say "all Nikoli puzzles". That seems to me to be a very broad mix of puzzle genres (not just one, like Fillomino-Fillia), constructed with elegance and logical solutions. I would not want to discourage tests with a broad range of puzzles, even if using classic styles and approachable puzzles means there are 3-4 solvers in the world who can have a remarkable time as deu does on a Nikoli Selection (3rd place at 72% of his score) or, with deu test-solving, me on Japanese Puzzle Land (2nd place at 79% of my score).

For example, does your description also include tests with "all Serkan puzzles" (Best of LMI Puzzle Tests was a runaway by Palmer, 10th at 63% of his score)? Does it include "all Deb puzzles" (Twist, with me finishing 30 minutes before second place was one of the largest runaways ever, and even without proper bonus 10th was 60% of my score)? Do you really mean single source in the way you seem to imply? I think your problem is not with the bonus system per se, but with dealing with the fact the best solver may indeed be twice as fast as the eleventh place finisher if it takes him 60 minutes to finish, and the player in 11th has 2 puzzles to go, both high value ones.

The most objective measure of two solvers is the total time they take to complete the test. Here only 6 completed, and 6th place took 40 more minutes than Palmer. 60/100 = 60%. That the scores earned (991.4/1665.3) also equals 60% is a feature, not a bug of the system. Palmer just solved that well. I'll welcome a more developed argument that normalization should be made to a solver besides #1 for the monthly rankings -- I'm not sure I'll agree -- but I will not accept an argument that a bonus system like each extra minute = 5 points is better. 991.4/1200 does make Kota much closer to Palmer, but he still finished 40 minutes slower. At the end of the day, that should mean something. This is the right bonus system to get raw score. Let's debate what to do with the raw score (and rank) to get the fairest annual ranking. In other words, the right discussion is on the ranking formula, not the bonus system, because in the fairest evaluation there were only 10-12 solvers likely to finish within 2x of Palmer's time.


Edited by motris 2012-07-25 7:46 AM

On the Instant Grading discussion:

I agree that it seems possible to consider typo versus puzzle error, on a case by case basis, as a test administrator, and give a "small" or "big" penalty. But there are many gray areas where it is not possible. For my Dotted Loop mistake, I entered 6 instead of 7 for the last row. This is a possible typo or miscount, as it is one off from correct. It also can come from a wrong loop with a touching segment. I don't know how, for this puzzle, to judge an answer ending with a 6 as just a typo, when an error in the solved form seems as likely or more likely. So I prefer to treat wrong as wrong.

I also hesitate, for the reasons Gareth points out, to use a strict time cut-off to try to separate one from the other. Having to spend extra time sorting it out seems extra penalty enough in combination with the flat cost of submitting something wrong.

So to me, the question is should each wrong submission be a fixed percentage of puzzle value, or a fixed point value, and I lean to the latter. But I think you have to treat wrong as wrong and nothing "cute" to separate particular kinds of answers can be fairly and uniformly done on these kinds of tests.

I have no problems with the tests. I enjoy all types of tests. I just meant that these types of tests can facilitate certain runaway performances, which maybe doesn't suit this bonus system. For that reason the single themed rounds in WPC's are usually shorter rounds with lower total scores, so the bonus can't get too big. If you were to use this bonus system in such a round, the bonus could get ridiculously big. Hideaki's bonus for Nikoli selection would have gone towards 100% of the total score as he saved 42 minutes on 90 minutes. Your bonus would have gone over 100% as you saved 46 minutes. At least that is my interpretation of the score page. I feel bonuses shouldn't be able to get this high. So my point was using your bonus system for those types of tests, might not be the best idea. I don't have a problem with holding these types of tests. I just brought up Nikoli, as I remember Hideaki and you doing particularly well on those Tom's last Nikoli selection. And that is very much caused by a high exposure to Nikoli genre puzzles and being far much trained in those genres. You won't find that many practise material in all Deb, Serkan or Naoki Inaba puzzle genres. That's really why I singled out Nikoli, as it makes a lot of difference.

So my main point is really that the bonus shouldn't get too big. I think it would be better if a big score difference comes from solving more puzzles than getting a really big bonus.