[gnugo-devel] Distrusting owl distrust

[bump]

At move 192 of the Saphir game, GNU currently plays the
right move at T6, however only by a smidgen:

Top moves:
1. T6  115.03
2. T4  112.93
3. S5  76.75
4. T2  33.56
5. B19 6.74
6. C11 5.44
7. D18 4.81
8. B10 2.71

Things look a little better if you increase increase
OWL_DISTRUST_DEPTH from 6 to 7 in utils.c.

Top moves:
1. T6  115.03
2. S5  76.74
3. T2  33.56
4. T4  17.10
5. B19 6.74
6. C11 5.44
7. D18 4.82
8. B10 2.72

The problem is that GNU thinks that T4 is owl defends O6.

For the record, I'm including the relevant reading at the
end as an sgf file.

Note the comment "getting deep, looks lively" where it looks
nothing of the sort. I've seen this enough times that I think
it's a problem.

Truncating some reading below owl_distrust_depth is necessary
for pruning absurd variations. In this example, the baby gets
thrown out with the bathwater. Maybe we should do this in
lines below an E pattern in owl_defendpats, but not otherwise.

Increasing OWL_DISTRUST_DEPTH from 6 to 7 added 268 seconds
or about 2.8%, which currently take about 9594 seconds to
run on an unloaded sporadic. We get a net gain of one test.

Dan

./regress.sh . nngs1.tst 
16 unexpected FAIL: Correct 'M4', got 'D5'
33 unexpected PASS!
./regress.sh . lazarus.tst 
16 unexpected FAIL: Correct '!L17|J5|K5|K6', got 'L17'
./regress.sh . trevorb.tst 
130 unexpected PASS!
./regress.sh . nngs.tst 
240 unexpected PASS!
./regress.sh . trevorc.tst 
940 unexpected FAIL: Correct 'G1', got 'F3'
./regress.sh . global.tst 
16 unexpected PASS!

(;GM[1]
SZ[19]
KM[0.0]
;AW[bc][cc][dc][gc][ic][jc][lc][bd][ed][gd][ld][ce][ee][ge][ie]
[ke][le][me][oe][cf][ef][lf][of][pf][qf][dg][fg][jg][qg][dh][fh]
[jh][kh][mh][nh][oh][ph][gi][li][mi][pi][qi][gj][lj][qj][rj][fk]
[hk][lk][ok][sk][gl][hl][kl][nl][pl][em][gm][im][km][nm][om][pm]
[qm][rm][sm][cn][jn][ln][mn][qn][eo][fo][go][lo][no][gp][lp][mp]
[op][fq][hq][iq][mq][nq][pq][sq][gr][hr][nr][pr][rr][ms][qs]
AB[eb][gb][hb][ec][fc][mc][fd][jd][kd][nd][od][pd][be][fe][ne]
[qe][ff][gf][hf][jf][kf][mf][nf][gg][kg][lg][mg][ng][og][pg][rg]
[gh][hh][lh][qh][rh][ei][fi][ii][ki][oi][ri][dj][jj][nj][oj][pj]
[ik][mk][nk][pk][qk][rk][cl][el][fl][il][ml][dm][hm][lm][mm][dn]
[hn][kn][nn][on][pn][rn][bo][io][jo][ko][po][qo][so][dp][ep][fp]
[jp][kp][pp][rp][eq][jq][lq][qq][rq][er][fr][ir][jr][kr][lr][mr]
[qr][is][ks]
;B[sp]C[owl_does_defend at O6 (variation 1, hash df35579b)
owl_attack O6: 0 (attack failed)
  (18 variations)
(next variation: 19)]
(;W[rs]C[save lunch at O6 (variation 2, hash c24fc1af)
owl_defend O6: WIN T6 (defense effective)
  (5 variations)
(next variation: 7)]
(;B[sr]C[eat lunch at O6 (variation 3, hash fccd56ea)
owl_attack O6: WIN T6 (attack effective)
  (2 variations)
(next variation: 5)]
;W[sn]C[vital move at O6 (variation 4, hash 33e7e75e)
owl_defend O6: 0 (defense failed - genus 0)
  (1 variations)
(next variation: 5)]
)
(;B[sn]C[vital move at O6 (variation 5, hash 88ee5ba0)
owl_attack O6: 0 (attack failed)
  (2 variations)
(next variation: 7)]
;W[sr]C[VA47 at O6 (variation 6, hash 645f504a)
owl_defend O6: WIN PASS (2 or more secure eyes)
(next variation: 7)]
))
(;W[sn]C[vital move at O6 (variation 7, hash 101fe62f)
owl_defend O6: WIN S1 (defense effective)
  (12 variations)
(next variation: 19)]
;B[rs]C[eat lunch at O6 (variation 8, hash adee511)
owl_attack O6: 0 (attack failed)
  (11 variations)
(next variation: 19)]
(;W[ss]C[save lunch at O6 (variation 9, hash 5e446fc)
owl_defend O6: WIN T2 (defense effective)
  (8 variations)
(next variation: 17)]
;B[sr]C[eat lunch at O6 (variation 10, hash 59b746fe)
owl_attack O6: 0 (attack failed)
  (7 variations)
(next variation: 17)]
(;W[]C[tenuki (ko threat)];B[]C[tenuki (answers ko threat)];W[sq]
C[tryko: VA13 (variation 11, 96a9d7f4)
owl_defend O6: WIN S5 (defense effective)
  (2 variations)
(next variation: 13)]
;B[ro]C[vital move at O6 (variation 12, hash 32d410d5, komaster white:T2)
owl_attack O6: 0 (getting deep, looks lively)
(next variation: 13)]
)
(;W[ro]C[vital move at O6 (variation 13, hash ae06bf58)
owl_defend O6: WIN S1 (defense effective)
  (2 variations)
(next variation: 15)]
;B[rs]C[eat lunch at O6 (variation 14, hash 685d60fb, komaster purple?:T3)
owl_attack O6: 0 (2 or more secure eyes)
(next variation: 15)]
)
(;W[rs]C[A902 at O6 (variation 15, hash 261c478d)
owl_defend O6: WIN Q1 (defense effective)
  (2 variations)
(next variation: 17)]
;B[ps]C[eat lunch at O6 (variation 16, hash 64484a4)
owl_attack O6: 0 (getting deep, looks lively)
(next variation: 17)]
))
(;W[ro]C[vital move at O6 (variation 17, hash 9fbe8bf0)
owl_defend O6: WIN T2 (defense effective)
  (2 variations)
(next variation: 19)]
;B[sr]C[eat lunch at O6 (variation 18, hash 685d60fb)
owl_attack O6: 0 (2 or more secure eyes)
(next variation: 19)]
)))