I think Deb is not here just now. I answer:

"I cannot find a start test on the TWIST page"

On the twist page, you must login before start. When you are logged, you'll see a big "start" button.

Fred

Very nice and fun test! Bravo, Deb!

Regarding the previous discussion, I think it's time to stop experimenting with bonus systems and try to establish criteria that would apply to all future tests. For such single and one-time events, the first view, of course, should be the score, and then the solving time. I think it's very enough.

Nikola

Arrgh

I am working on a very old laptop and I have just discovered a very small button half way down a blank page and I have started.

Thanks Fred

Now that the contest is almost over, I can explain what was intended using some numbers.
I've always believed and encouraged that LMI contests should run longer than the time top solvers take to solve all puzzles. This make sure that top solvers solve all puzzles and other get more time solve puzzles.

In this test, I was thinking at least 2-3 players can solve 24 puzzles in 90 minutes, and may be few more players in 120 minutes, and some more players should solve 22 or 23 puzzles in 120 minutes. If I'm running a test 33% longer than what a top solver can finish in, we need to give enough time bonus for top solvers. But I decided to not give any time bonus, instead reduce the point value of puzzles.

Rohan, Palmer and Thomas were one of the first few guys to participate, and looking at their results, I thought the timing is correct.
But that was not to be, 90 minutes was ill-timed, and if the point-reduction-system was not successful, it is because of wrong chosen Test.
As few of you have noted, a FLIP or a Broken Pieces kind of test will show its true value.

Without summarily accepting or rejecting it, I think we can give it a try again when we can plan a proper Test.

Congratulations to Thomas, Ulrich and Hideaki for topping in Twist.
Thomas solved all 24 puzzles in an incredible 86 minutes. Ulrich is the other one to solve all 24.

Among Indian results, Rohan is in top 10. That is an incredible performance IMO. Hope to see him get better.

Thank you everyone for participating.

I'm not completely surprised that all the discussion is around the point structure :-)



I'm not exactly sure if that is true.

If I ran this test for 120 minutes flat, motris would have got 869. This thing is one could argue for symbolic time bonus of 1 point per minute saved, but I always felt time bonus should be appropriately computed. Otherwise, it simply undervalues the exceptional performances by top solvers.

If the test was for 90 minutes, motris would lose 15 points to be at 719, but others would lose all the points they got for last 30 minutes.



Ok, agreed that the table above can't be exact since players' strategy could be different if the test ran for 120 minutes flat or for 90 minutes.
But I feel it provides very approximate information.

Link to solution booklet and Link to Puzzle booklet without password

I liked the bonus system - I especially appreciate the motivation - allowing the average competitors to have enough time to make a good attempt at more of the puzzles.

I think it worked nicely here. (and, it helped, that the puzzles were all excellent)

Thanks :)
Ronald

I would be interested in the approach for missing breakpoints (the bigger one) ... if someone can point a couple of starting steps, that'd be great.

Edited by rakesh_rai 2011-04-11 8:55 AM

You can identify two missing circles (one in Column 1 and one in Row 1) without drawing a single line.
Did you get there?

I am very poor at such puzzles....I could get one missing circle for column 1, hopefully its correct...for row 1, still not sure. Here's where I have got to, so far. (I don't want to look at the solution before solving it completely)

Given that it was solved by only 6 players correctly, I don't think you need to feel that you are poor at it.
The thing with Missing Breakpoints is that it uses 2 properties of standard ESB puzzle heavily. If you don't use it, the puzzle will turn out to be a trial&error.

Property 1 - About Corners
In a valid ESB puzzle, exactly 2 (out of 4) corners will have circles. More ever, these 2 circles will be opposite to each other.
So, using this property, you immediately put a circle at R10C1.

Property 2 - About adjacent circles.
Check the image below. If there are 2 adjacent circles, 2 of the 4 combinations are ruled out.


From this property, we can deduce that in the border rows or columns, 2 circles can not be adjacent to each other.

Applying this property, you can put a circle at R1C6 without drawing any line.

Using these 2 circles, you can proceed for upto this point

Both of those properties are part of a more general topological one that I found indispensable in my own solve (which goofed the end with two breakpoints in one row). In this particular puzzle, the breakpoints are placed such that if a square has a breakpoint turn where the majority of the square is outside the loop (any square on the edge has this property), then the turn must go up-right or down-left. Similarly, if the majority of the square is inside the loop, then the breakpoint turn must go up-left or down-right. This applies in reverse to turns which have no breakpoint.

Finally about Twists :

The EverGreens series at LMI were very popular, and Rakesh/Rohan wondered if we should do an EG3 at LMI. I was independently working on Twist, and I thought it might be a good idea to have Twist instead of EG3.

I decided to stuck to EverGreens format i.e. lot of easy puzzles and some hard puzzles.

Applying the twists were not easy, because I wanted a simple rule change to each puzzle. So all kind of Hybrids were ruled out. I'm personally happy with the kind of puzzles I chose. Even if the rule change is minor, the solving approach changes drastically in some puzzles (e.g. LightUp, Hitori). While in some other puzzles, one just needs to solve like the standard puzzle with the additional rule in mind (e.g. Fence/Minesweeper). But some puzzles resulted in completely different puzzles (e.g. ESB/Sudoku - unfortunately those two types turned out to be hardest ones). The rule changes to Masyu and Arrows are something I was not comfortable with (especially Arrows because it became too error prone).

Despite the debatable points-reduction system, I hope that everyone found some puzzles enjoyable.

And finally, thanks to Branko once more for pretesting all puzzles. I used his timings as a guidance in determining the points, but the timing structure of 90+10+10+10 was set by me, which could have been improved.

Considering that lot of puzzles turned out to be very different from the standard types, we'll probably should have EG3 sometime soon :-)

Ken, I'm glad that things worked out fine at the end.
Posting the password on forum is definitely not advisable while the test in running. If someone wants to compete the test unofficially, they should request for password in email.

About answer format - I was very much impressed by the answer format used in TVC. Most of the answer keys were driven by that (all loop puzzles, minesweeper)
In EG2, the answer keys I chose were really difficult, but I'm certain that the answer keys in Twist were relatively easier.

There seems to be lot of wrong answers in No 3 in Minesweeper (Top), but I feel they are because of wrong solves rather than bad answer key. Same about Fence.

The answer key for Arrows were probably more difficult, but I didn't know of a better answer key. I personally know 2 players got it wrong after solving the puzzle correctly.

The answer key for LightUp was little bad - because in the top puzzle it didn't require to solve the puzzle fully.

Deb, thank you very much for wonderful test! I had very enjoyable 2 hours in the weekend. And of course i like the point system, i think it is very useful. I tried to solve hard puzzles in begining, some of them was solved smoothly, some of them not solved, and they caused some trouble for me. During the test i forgot some rule additions of some puzzles like hitori, like minesweeper, and i spent more time for these puzzles, i was a little upset for this. Because i can get easily more than 400 points. But anyway i like your puzzle style, contest format, nice instruction booklet, very useful points system. So thank you very much, and in my language "Tesekkur ederim" :)

Best,

Serkan

Deb, let me add my thanks for an excellent competition. Personally, I don't particularly care about the point system, but this one seemed more fun than most. For the 99% of people who are not going to finish in 90 minutes, it gave us something to think about. Thanks for the tip about the adjacent circles in Breakpoints, although knowing that meant the puzzle took me 2 minutes max, rather than the 30 minutes that I wasted not solving it in the competition :)

Thanks again.

Steve, I figured that your strategy of "solving all easy puzzles first before cracking the difficult ones" is best. I didn't follow everyone's progress so others might have followed similar strategy.
Congratulations on topping the UK chart this time.

The Missing Breakpoint properties mentioned above are really interesting. As a self-taught puzzler I tend to just hit everything with a hammer and hope it works. Is there somewhere online that people discuss these puzzle-solving theories?

We try to do that for some puzzles in every test. But we don't do it consistently enough.
It is always interesting to discuss how the author expected players to solve a puzzle vs how players solved it.

Twist LightUps were not difficult by any standard (although they were not solved by many)

I had solving methods documented for them, so thought of sharing

Thanks Deb for this excellent test.

My original strategy was to try to solve all the easy puzzles and then some hard ones if possible, but I changed my mind because some puzzle types were so attractive that I really wanted to try both puzzles. Finally I solved puzzles only according to my likes, but still hoping to get at least the equivalent amount of points of all the easy puzzles ; and I did so despite some silly mistakes. So, good operation.
The puzzles themselves (the ones I solved) were very nice, and several were better than that. As expected, rectangles were fun to solve, as were masyu (especially the little one). Fences were pretty easy but, again, fun. Just forgot to send the answer for biggest one... Both hitori were excellent. I solved the second one after the test and it was really great (and a bit strange) to have so much pleasure on hitori.
I couldn't solve the biggest "breakpoints" but the smallest was nice too, etc.

All in all, an affordable test but with some tough puzzles for strongest solvers... Many beautiful grids... Nice job, really.

I think this is exactly what Deb intended :-)