This post is going to look more at completion and error rates, comparing this year to historical (-ish) averages; part 3 will look at the “par score” concept (which doesn’t require the full stats, so I can do that for more years).
We have “full” stats (including # of minutes and # of errors) for all the tournaments from 2010 onwards, so for this post “history” will be 2010-2015. This year the puzzle sizes changed, which may make part 3 a little weird (since that involves scores on individual puzzles), but this post will just involve percentages so we should be fine. With all that said, here we go:
- Puzzle 1 historically has 94.9% complete and 14.2% Oops!; this year was 90.8% complete and 11.2% Oops! This is the lowest complete rate in my records (previously 2010 was 92.4%) which corresponds with my opinion (which seemed pretty widely-held) that this was one of the hardest puzzle 1’s we’ve had. (Looking ahead, only puzzles 3 and 5 had a lower completion rate, making this probably the first tournament ever where puzzle 1 was the third-hardest puzzle in the event.) Since Oops! is a strict subset of the complete rate, a lower complete rate will naturally knock down the error rate too, so that doesn’t seem unnaturally low (the lowest Oops rate for a puzzle 1 was 2013’s 7.7% out of 96.5% complete).
- Puzzle 2 historically has 65.7% complete and 19.5% Oops!; this year was 91.4% complete and 33.2% Oops! This is, by far, the highest complete rate for a puzzle 2 (the previous high was 2013’s 80%) This is the first year in the records, and probably the first year ever, that puzzle 2 played easier than puzzle 1. I have, somewhat empirically/arbitrarily, decided that an Oops! rate that is more than one-third of the complete rate suggests there may have been a tricky crossing somewhere; by this guideline, four of the seven puzzle 2’s in the records have had such a thing, so that’s fairly typical.
- Puzzle 3 historically has 58.5% complete and 18.4% Oops!; this year was 79.1% complete and 31.1% Oops! Again this is unusually high; the previous high was 2011’s 68.3%, so it seems unlikely that this was a re-purposed puzzle 5. Again a rather high Oops! rate suggesting a tricky crossing; one of three puzzle 3’s with a high rate. As a pure number this is also by far the highest Oops! rate, but again that’s tempered by the unusually high complete rate.
- Puzzle 4 historically has 91.5% complete and 20.3% Oops!; this year was 92.0% complete and 6.5% Oops! This is the cleanest puzzle 4 we’ve ever had (the previous low Oops! rate was 11.2% in 2014), although there’s only been one puzzle in the records with a suggested tricky crossing (last year’s).
- Puzzle 5 historically has 22.4% complete and 5.8% Oops!; this year was 37.3% complete (highest in records) and a 13.3% Oops! rate (also highest in records). In fact this Oops! rate is high enough that it trips my sensor for a tricky crossing, although I don’t remember much buzz about it (and I had to leave before getting copies of the puzzles, so I can’t yet check). This is the only puzzle 5 with an error rate above that threshold.
- Puzzle 6 historically has 93.1% complete and 32.5% Oops!; this year was 93.9% complete and 20.2% Oops! This year, this was the easiest (by completion rate) puzzle, which isn’t all that uncommon. Puzzle 6 generally has a rather high error rate, even when the tricky-crossing sensor doesn’t go off (whether because of size, or it being late in the afternoon, or just as a reaction to puzzle 5), so this year was relatively clean.
- Puzzle 7 historically has 81.9% complete and 31.3% Oops!; this year was 93.7% complete (highest in records) and 23.2% Oops! rate (lowest in records, even without adjusting for higher solve rate). Puzzle 7 also generally has a high error rate (the historical range 26-40%); a few meet the threshold for tricky crossings, but even the ones that don’t are fairly high; again I’m expecting that to be mostly based on size.
I had definitely heard buzz this year about puzzle 1 being harder-than-average and the puzzles being generally cleaner (in terms of fill) than usual, and both of those are borne out by the data (the latter looking at the lower-than-usual error rate). That last, certainly, is a trend I think we’d all like to see continue.