X-Git-Url: https://mattmccutchen.net/match/match.git/blobdiff_plain/17e0995d8f3673797f5280189e28e727db454f7f..08f65a95a67fa8835b97a387d9d1e285972ca22a:/paper/paper.tex diff --git a/paper/paper.tex b/paper/paper.tex index 7ce6770..fd0bd2c 100644 --- a/paper/paper.tex +++ b/paper/paper.tex @@ -21,7 +21,6 @@ \usepackage[letterpaper,left=2.6cm,right=2.6cm,top=2.6cm,bottom=2.6cm]{geometry} -\usepackage{floatflt} \usepackage{pstricks} \usepackage{delarray} @@ -70,11 +69,11 @@ thirty to forty program committee members. From now on we will focus on the problem of assigning papers to reviewers. We assume that each reviewer is given access to the -list of papers to be reviewed, and gives each paper both a ``desirability'' +list of papers to be reviewed, and gives each paper both a ``preference'' score indicating his/her level of interest in reviewing the paper and an ``expertise'' score indicating how qualified he/she is to evaluate the paper. -(Some organizations may choose to use a single set of scores for both -desirability and expertise. We believe that making this distinction may better +(Some organizations may use a single preference score and assume that it +also indicates expertise. We believe that making the distinction may better model the real-world objective.) A reviewer may also declare a conflict of interest with a particular paper, meaning that he/she is forbidden to review the paper. @@ -140,8 +139,8 @@ Flow can pass from $s$ through one or more of the nodes $r^t_i$ and one or more of the nodes $p^t_j$ to the sink to represent a review by reviewer $i$ of paper $j$. -Each paper has an edge of capacity $r$ to -the sink, indicating that it needs $r$ reviews. In general, these +Each paper has an edge of capacity $q$ to +the sink, indicating that it needs $q$ reviews. In general, these edges will constitute the min cut, so any max flow will saturate them and thereby provide all the required reviews. We take the min-cost max flow in order to provide the reviews in the ``best'' possible way. @@ -160,24 +159,24 @@ to a solution that loads one reviewer by $L$ and the other by $L+2$ unless the load imbalance in the second solution is outweighed by other benefits. -For each reviewer $i$ and proposal $j$, there is a unit-capacity edge from $i$ +For each reviewer $i$ and paper $j$, there is a unit-capacity edge from $i$ to $j$ allowing that pair to be assigned, unless the reviewer declared a conflict of interest, in which case the edge is not present. The edge cost is -based on the desirability value $d_{ij}$ stated by reviewer $i$ for proposal +based on the preference value $a_{ij}$ stated by reviewer $i$ for paper $j$. For values on the NSF scale of 1 (best) to 40 (worst), we chose the cost -function $(10 + d_{ij})^2$, in an attempt to provide an incentive to avoid +function $(10 + a_{ij})^2$, in an attempt to provide an incentive to avoid really bad matched pairs without completely masking the difference between a good matched pair and an excellent one. This choice seeks only to achieve a natural relationship between a linear preference scale as normally interpreted and the costs to be used in the optimization. We realize that strategic -reviewers will take the cost function into account in choosing what desirability +reviewers will take the cost function into account in choosing what preference values to submit, in which case its form matters little. Alongside these purely additive per-review costs, we want to avoid an individual reviewer getting too many papers he/she does not like. With respect to a reviewer $i$, we classify papers as ``interesting'', -``boring'', or ``very boring'' based on their desirability values; +``boring'', or ``very boring'' based on their preference values; the thresholds for these classes are currently the same for all reviewers. The edge for reviewer $i$ and paper $j$ leaves from $r^1_i$ if $j$ is interesting, $r^2_i$ if $j$ is boring, or @@ -205,15 +204,15 @@ unit-capacity edge of cost $-c_1$ from $p^1_j$ to $p^3_j$. In addition to the bonus edges, there are edges of zero cost and unlimited capacity that reviews can follow from $p^1_j$ to $p^2_j$ and from $p^2_j$ to $p^3_j$ in order to reach the sink. -The choice to offer bonuses for two reviews was based on the value $r = 3$; -this would be easy to change for other values of $r$. +The choice to offer bonuses for two reviews was based on the value $q = 3$; +this would be easy to change for other values of $q$. In the example in Figure~\ref{flow-fig}, paper 1 is interesting to reviewer 1 and boring to reviewers 2 and 3. Reviewer 2 is expert on paper 1, with reviewers 1 and 3 merely knowledgeable. (Reviewer edges for paper 2 are not shown.) This illustrates how, in principle, -the desirability and expertise relations might differ. +the preference and expertise relations might differ. Each is taken into account at a different stage of the construction. The cost of a flow (assignment) is the sum of its reviewer overload costs, @@ -269,9 +268,9 @@ document may be browsed or downloaded at (NOT YET): There are currently two branches: \begin{itemize} \item \code{master} has the tool as originally designed for NSF, with no -distinction between desirability and expertise. +distinction between preference and expertise. \item \code{popl2012} is the basis of the version used for POPL 2012. The main -differences are that it has separate desirability and expertise, support for +differences are that it has separate preference and expertise, support for ``fixing'' previously chosen reviewer-paper pairs (buggy, however), and the special ERC gadget. \end{itemize}