Many organizations have turned to alternative voting systems such as
instant-runoff voting for determining the outcome of single-winner elections.
It is our position in this paper that the increasing deployment of such
alternative systems necessitate the study and development of risk-limiting
audits for these systems. We initiate this study. We examine several commonly
used single-winner voting systems and provide risk-limiting auditing procedures
for them. In many cases the methods from auditing plurality contests can be
applied with minor changes and little loss in efficiency. For instant-runoff
voting (IRV), the situation is markedly different. We describe an algorithm for
auditing the candidate elimination order using plurality methods which is
risk-limiting. Standard risk-limiting methods can be employed if the margin of
the election can be efficiently calculated or bounded. We provide efficiently
computable upper and lower bounds on the margin and, when known, compare them
to the exact margins. Both auditing algorithms are potentially far less
efficient than the methods to audit other types of voting systems.
Pre-2018 CSE ID: CS2011-0967