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Probability of Outcome for a Given Rating Difference

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RobertandtheDogs

I am trying to find or develop a guide for predicting the probable outcome of a game given a certain difference in ratings between the players.  For example, I have a vague recollection that a difference of something like 150 points will result in a win for the higher ranking player about 80% of the time.  I would like to know how to predict the probably outcome for other differences.  Does anyone know of a source of information about that, maybe a table, or a formula, or a guide of some kind?

Martin_Stahl

https://www.fide.com/fide/handbook.html?id=172&view=article

Table 8.1b

Table of conversion of difference in rating, D, into scoring probability PD, for the higher, H, and the lower, L, rated player respectively.


D

PD

D

PD

D

PD

D

PD

Rtg Dif

H

L

Rtg Dif

H

L

Rtg Dif

H

 L

Rtg Dif

H

L

0-3

.50

.50

92-98

.63

.37

 198-206

.76

.24

345-357

.89

.11

4-10

.51

.49

99-106

.64

.36

 207-215

.77

.23

358-374

.90

.10

11-17

.52

.48

107-113

.65

.35

 216-225

.78

.22

375-391

.91

.09

18-25

.53

.47

114-121

.66

.34

 226-235

.79

.21

392-411

.92

.08

26-32

.54

.46

122-129

.67

.33

 236-245

.80

.20

412-432

.93

.07

33-39

.55

.45

130-137

.68

.32

 246-256

.81

.19

433-456

.94

.06

40-46

.56

.44

138-145

.69

.31

 257-267

.82

.18

457-484

.95

.05

47-53

.57

.43

146-153

.70

.30

 268-278

.83

.17

485-517

.96

.04

54-61

.58

.42

154-162

.71

.29

 279-290

.84

.16

518-559

.97

.03

62-68

.59

.41

163-170

.72

.28

 291-302

.85

.15

560-619

.98

.02

69-76

.60

.40

171-179

.73

.27

 303-315

.86

.14

620-735

.99

.01

77-83

.61

.39

180-188

.74

.26

 316-328

.87

.13

> 735

1.0

.00

84-91

.62

.38

189-197

.75

.25

 329-344

.88

.12

 

 

EscherehcsE

You can use the table that Martin_Stahl posted, or you can use the "Standard winning expectancy" formula at the bottom of Page 11 of this document:

http://www.glicko.net/ratings/rating.system.pdf

 

RobertandtheDogs

Thank you for your reply Martin_Stahl

RobertandtheDogs

Thank  you for your reply EscherehcsE