blue wrote:DonM wrote:2. The over/inappropriate of computer solvers has affected the advance of good Eureka notation. A number of the computer solvers were programmed years ago and will spit out contructs and/or various terms that were defined/used in the first fews years of sudoku, but which were eventually no longer used as it was determined that either they could be incorporated into Eureka notation or they should be totally discarded as being too assumptive. I find it startling to periodically see some of these be resurrected on this forum as if we are back in 2006-7.

Hi Don,

You've used the term "assumptive", and mentioned the idea that some things can be "too assumptive", and (perhaps) used the word in other ways, recently ... "least assumptive", I think (?) ... but I've never been able to grasp exactly what you mean.

Can I prevail upon you to do your best to clarify the meaning(s) ?

E.g. "more or less assumptive than something else" ... what might that mean ?

I'm guessing that techniques like singles, locked sets and unfinned fish, you'ld classify as being "non-assumptive" (?).

Also, would you shed some light on a threshold (or threshold area) where you perceive that things have become "too assumptive" ?

Couch it in terms of "IMHO", if you like. In fact, please do.

(Okay, assume all of this as being 'IMHO")

To start with, I've never been totally happy with the term 'assumptive'. One of the many definitions of it that I would find relative would be 'assuming something without proof'. But in the end, here we're really talking about the degree of guessing.

Keeping in mind that we are talking about a puzzle game, my challenge in solving is to keep the element of guessing to a minimum and that means using as many proven patterns as possible. Just for reference, at the extreme of greatest assumptiveness or most guessing would be the use of the forcing chain method where you randomly start with one digit in a bivalue cell, see where it goes and then start with the other digit and do likewise. This requires the use of minimal logic- it's essentially a mindless exercise. At the other extreme of least assumptiveness (least guessing) would be finding something like an x-wing or a naked pair. The finding of these patterns is the real fun of solving sudoku- you find the pattern and the resulting exclusions are reliable and proven.

As the puzzles get more difficult, the less you will be able to use the simpler patterns to solve them. The increasing complexity of Eureka-notated chains to solve increasingly difficult puzzles is an exercise in using what is really an exercise in finding patterns that are more obscure than an x-wing, but are patterns nonetheless. For instance, after one has become more experienced in the pattern solving process, doesn't one get to the point that you can see a pattern of strong links that you've learned will often lead to an exclusion? If one can quickly see the exclusions that result from a simple naked pair pattern, isn't it a short jump to see the exclusions possible from a simple almost naked pair (ALS) pattern?

When you get to the really difficult puzzles, it seems self-evident that the element of assumptiveness is going to increase. When one uses one Kraken cell chain (essentially trifurcating a cell) to solve a puzzle, isn't one getting farther away from pattern-solving than if one used 2 chains each with perhaps an ALS or somesuch? I still consider that there are elements of a pattern in Kraken solutions, but just less so than in simpler chains.

What is the threshold for too much assumptiveness? It's a difficult question because some of it is subjective and some of it depends on what the objective is. On this forum, the objective (that seemed to develop almost unspoken some time ago) has been mostly to solve these daily puzzles with one-line solutions. That sometimes requires using constructs that wouldn't be considered as appropriate if the objective was to use the simplest chains possible even if more than one was required. Still, even with the one-line objective, I would find anything bordering on the forcing chain method as being mindless guessing which doesn't require any skill, doesn't improve one's skillset and isn't any fun (remember this is all IMHO ).

Digressing: While I understand the fun of doing these daily puzzles with one-line puzzles, my concern about there not being at least the occasional more difficult puzzles is that new solvers will think that bifurcating methods, just writing 'if this then that, if that then this' or using various coloring methods is all you need to solve any puzzle, no matter the difficulty. Plus, one's solving skills aren't likely to increase beyond a certain point.

From what I remember about the Eureka forum, the conversations could become a little heated. In fact, it was so bad (in that way) that after just a few visits, I tended to avoid it like the plague.

If one looked closely, there really were only a few individuals who routinely stirred things up. The view I chose to see were the incredible minds that took the time to make sudoku solving an incredibly rewarding pastime. Even so, the most devisiveness occurred circa 2006-8, but during latter 2008 and on there was a period of very productive manual solving of the 'extremes' where most everyone had a positive demeanor and was cooperative in keeping to reasonable standardization. BTW, anyone remember The Eureka Challenge?

This is a side issue, but: I wonder if you think that there may have been advances in "Eureka notation" over the past (almost a full) decade, and that it might be worthwhile to view it as an "evolving standard" ?

It is, but all I would ask is that any changes be made based on sound Boolean logic, that they be as intuitive as possible (ie. the expression of the pattern be as easy to discern as possible) and that the changes not be made to make life easier for the writer at the expense of understanding by the reader.

This post has become somewhat long-winded, but I responded with the same seriousness that seemed intended by your question.

Regards,

Don