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To streamline the review process and to prevent overloading reviewers since 0.9.1 the tiebreaker concept was added. When a user is a tiebreaker for a paper they will only be asked to review this when the other reviewers cannot agree. This means that the list of papers a reviewer should review is shorter (but can become longer over time when there are more tiebreaks required). When a tiebreak becomes necessary the tiebreaker automatically receives an email asking their review for the particular paper. You can configure this behaviour by changing the value of application.ini/core.observer.tiebreaker to 0.
Whether or not a tiebreak is required is decided with the following algorithm.
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