# BQM 348

golearner -- Here's the end of a close game. Playing as White, I lost by 1.5 points! (In other words, at the final count, Black won this game by 1.5 points.) I wonder if I made the right plays, in the right order, or if I need to look earlier... (Actually, I suspect I do - I would have lost by a couple more points if Black hadn't filled in some territory unnecessarily.) Captures prior to this point: Black = 4, White = 12. Based on comments so far, I've tried to evaluate the starting position - that's at the end of this page. (I'm sure I've made some mistakes in values though...)

LukeNine45: I think should be at if you're taking gote in the corner there anyway.

golearner: Yeah, I'm not sure there was any value to playing there - I thought that during the game right after doing it...

Harleqin: is unnecessary, losing a point in gote. Black should first play sente at 257, then 2 points gote at 256. is minus half a point in gote. Note that Black could only play here anyway, but now he gets it in sente. Instead, White should play 2 points gote at the left side (where move 253 went).

unkx80: Locally, should be played at White *a*, Black *b*, White at . I don't think Black dares to play at *c* because White *d* will turn it into a ko. Because after my sequence, Black must connect at *d* anyway, I will assess the loss of the actual to be 2 points.

Harleqin: loses a point, should first exchange for , then hane and connect. The rest are neutral points.

Harleqin: and are unnecessary, losing a point each. If you were playing by area scoring, then each pass loses a point for black, too.

Dave: I think the first question is whether is sente. If White plays away (e.g. ), what happens after - ?

golearner I've calculated the following - let me know how far off I am!

Black: White:

AREA 1 (top line) - double gote

A, B, C C, V, W, X, A

B+3 W+1

Area worth 4/2 = 2

AREA 2 (left side) -double gote

D, E, F F, Y, D

B+1 W+1

Area worth 2/2 = 1

AREA 3 (bottom left) - two parts, first sente, second gote

Part 1 - sente:

G,H H,G

Area worth 0 points.

Z Z,b,a,d,c

0 W+1

Area worth 1/2.

AREA 4 (line F) - sente/gote

I,J I

0 W+1

Area worth 1/2? How do you calculate the value when it's sente/gote?

AREA 5 (line L) - Same situation as AREA 4.

AREA 6 (line 6) - sente/gote

M,N N

Value = 0

AREA 7 (right edge) - gote/sente

O, P, Q, R, S Q, e, O, S

B+1 0

Value = 1/2?

Harleqin: As far as I can see, Area 1 is double sente (see Dave's contribution above). Also, after white C, black V, Black has W as sente, while it is gote for White, so you can assume W is Black's privilege. In your terms:

Black: White:

AREA 1 (top line) - double sente

A, B, C, protect C, V, later Black has W, A

B+2 W+2

Area worth 4.

golearner: Okay, I think I see that. (I hadn't realized the trouble Dave's idea causes White in the corner.) It looks like area 1 is the hottest area.

Dieter: there is also another point in area 2, so 3 pts double gote, and one more point in 3

golearner: I'm not sure how you're getting the extra points there, unless it's area vs. territory scoring.

Harleqin: Nothing like that. It is just that, if White gets this endgame, Black has to protect again when the outside liberties are filled.

Bill: **a** is technically White's sente, since it threatens Black's huge group. I think it is worth 9 7/9 points, but I'm not exactly sure. The main thing, as Dave and Harleqin show, is that at this point it is double sente.

**b** is a gote that gains 1 1/2 points. If White plays there Black will have to fill at **z** later, as Dieter points out.

Everything else is worth 1 point. **c**, **d**, and **e** are Black sente; **f** is ambiguous, sort of like White sente; **g** is a gote that gains 1 point (As unkx80 points out, if **Wg** Black must later protect around **y**.).

Bill: First, Black takes the double sente, and then takes his sente.

Dave: Bill, is sente in this situation? Is it possible for White to pick up a point by playing at ** a**? White is 3 points better for having played

**, but and**

*a***in sente give Black 2 points back. I am thinking of**

*d***and**

*b***as miai, but I am not sure whether I am correct overall.**

*c*Bill: White only gains 1 1/2 points by a gote at **a**, but gains 2 points by a reverse sente at . However, because of tedomari, I don't think it affects the result. See the *alternate play* diagrams below.

Bill: Next, Black gains 1 1/2 points with - . threatens , a 2 point sente. Black does not respond to , but plays to get the last play with . I think that puts Black 10 points ahead on the board.

Bill: Although technically the gote, in the previous diagram, which gains only 1 1/2 points, is smaller than the reverse sente at , which would have gained 2 points, White gets the 1/2 point back because Black gains only 1 point with in this diagram. The end result is the same as the suggested play. By comparison White gains 3 points on the left side but loses 2 points in the center and 1 point on the right side. (The swing points are marked.)

Bill: Your last mistake was 248, which loses 1 point in gote. W246 should have been at 253, but that is unlikely to win. As it was, you gained 8 points against par in this endgame! Thank your lucky stars for that.

elsewhere

Bill: Earlier I said that White's atari at was sente. That means that - is gote. Here is a little about responding to .

(At this point in the game should be at , OC.) But in this situation I think that is the right response to , to avoid worse. (See Dave's diagram.) Earlier in the game the next diagram is normally correct, I think.

elsewhere.

Bill: This is the sequence I used to calculate the size of the play. It ends in gote with . (Later - is sente.)