Pairing Logic - Pairings Menu
This dialog shows how players were moved from their original (“natural”) locations. This happens when SwissSys improves color allocation in accordance with the guidelines detailed in the USCF or FIDE rulebooks.
These guidelines include priorities for making the various player swaps, and the rating point limits that should not be exceeded in each case.
The dialog works slightly differently depending on whether the USCF or FIDE pairing system is in effect.
Understanding the Display
The pairing logic dialog shows variations from natural pairings which were caused by switches to improve color allocation or to improve the choice of oddmen.
Here the term “natural pairings” refers to those pairings expected AFTER making necessary switches to avoid rematches or other strictly illegal pairings.
This dialog can help answer player questions such as “Yeah, but why didn’t you switch me with so-and-so?” Even in this case, though, the pairing logic dialog should give you a good starting point.
The display shows pairings just as if you had the old-fashioned pairing cards laid out on a table.
This means that players on the left hand side are from the top half of their score group, and those next to them on the right hand side are their natural opponents from the bottom half. (Color has nothing to do with player location in this dialog.) For greater clarity, score group breaks are underlined.
Line Color Codes
If a line connects a player with their natural opponent, the natural pairing was preserved.
If a line does not connect a player with the natural opponent, the color of the line holds information about what the justification for the switch was.
These color codes are listed in a legend at the top of the dialog, and are given here with a brief explanation:
Avoiding consecutive colors - The switch was required to avoid three black or white in a row.
Eliminating bad color equalization - The player was originally expected to be matched against another who was due the same color for equalization.
Eliminating bad color alternation - The player was originally expected to be matched against another who was due the same color for alternation.
Side effect with minimum consequences - The term “side effect” refers to the process of finding a match for the original opponent of someone switched for one of the reasons above. The idea is to find the opponent closest in score and rating, and due the optimum color.
Improving oddman/float for color or rating - The player (or an opponent) was originally set up as the oddman of the scoregroup, but a better oddman was found. This switch could happen either to improve colors, or to avoid using an unrated player as the oddman — something even experienced TDs sometimes forget!
Avoiding rematch, other illegal matchup - The switch was required to avoid an illegal pairing.
Better float for color or repeat float - The player (or an opponent) was originally set up to float to the next pair bracket, but a better float player was found.
Color Due Indicators
Players show color indicators: W = strongly due white (for equalization); WW = due white to avoid three consecutive colors or other illegal imbalance. Similarly for players due black.
Additional Features
For statistics about the problems SwissSys encountered in adjusting USCF pairings, you can click on the Problem summary button.