Chess South Africa Ratings Database

Surname or Chess SA id..

PLAYER TOURNAMENT DETAILS

Jonah Robertson

1120112288
Cape Winelands (WCW)

Tournament details

Tour Id	20260131
Group Id	20260125
Name	Marie Delport Memorial 2026
Section	Open
Rounds	6
Format	Swiss
Type	Standard
Start	2026-01-31
End	2026-01-31
Submitted	2026-02-02
Rated	2026-02-06
Submit age weight	0.55
Host	Cape Winelands (WCW)
Total time	70
Time weight	0.87
Official results	Official results

General

Games	6
Score	4
Percent	66.7
Dp	141.7
Aor	1378.2
Perform	1519.9
Penalties	0
Wins	3
Draws	2
Losses	1
White	3
Black	3
White wins	1
Black wins	2
Default wins	0
Default losses	0
Byes	0
Half byes	0
Rank	1
Final Pos	10
Share Pos	7
Count for rating	Yes

Analysis (Main)

Rating	1623.4
K-factor	20
Score	4
Expected score	4.71
Score - Expected score	-0.71
Rating +/-	-12.4

Analysis (Type)

Rating	1587.7
K-factor	20
Score	4
Expected score	4.56
Score - Expected score	-0.56
Rating +/-	-11.2

Opponents

Round	Date	Opponent	Fed	Title	Main	Type	Col	Res	Main			Type			Cfr
Round	Date	Opponent	Fed	Title	Main	Type	Col	Res	We	Swe	+/-	We	Swe	+/-	Cfr
1	2026-01-31	Geyer, D (David)	WCW		1271.6	1265.4	B	1	0.87	0.13	1.2	0.83	0.17	1.9	Yes
2	2026-01-31	Davids, JW (Jo-Wayne)	WCW		1484.4	1439	W	0	0.7	-0.7	-12.2	0.71	-0.71	-14.2	Yes
3	2026-01-31	Grobbelaar, A (Altus)	WCW		1259.5	1261.7	B	1	0.88	0.12	1.1	0.84	0.16	1.8	Yes
4	2026-01-31	De Lange, R (Rhailihn)	WCW		1369.1	1357.7	W	1	0.84	0.16	1.5	0.81	0.19	2.1	Yes
5	2026-01-31	Groenewald, W (Willem)	WCW		1519	1499.3	B	0.5	0.58	-0.08	-1.4	0.56	-0.06	-1.2	Yes
6	2026-01-31	Roux, A (Adriaan)	WCW		1365.9	1358.3	W	0.5	0.84	-0.34	-5.9	0.81	-0.31	-6.2	Yes