Edges

Bids, assignments, affinity scores, conflicts, etc. are saved as Edges in OpenReview.

You can read more about Edges in the reference section depending on the API version: Edges V1, Edges V2

Simply speaking, Edges are links between two OpenReview entities (Notes, Groups, Profiles, etc.).

Besides the fields that define user permissions, an Edge would usually contain these fields: head, tail, weight, label.

For example, a OpenReview affinity score edge for a paper-reviewer pair may have the reviewer’s Profile id set in the edge.head field, paper id set in the edge.tail field, and OpenReview affinity score set in the edge.weight field.

All Edges respond to some OpenReview Invitation, which specifies the possible content and permissions that an Edge is required to contain.

Because the amount of Edges can be quite large, depending on the query used, you need to pass at least one of the following parameters: id, head, tail.

For more information on the available parameters, check the corresponding OpenAPI reference: Edges V1, Edges V2.

Note that the groupby parameter is only available in the method get_grouped_edges described below.

Consider the following example which gets the first 10 Edges representing the “Personal” conflicts in ICLR 2020:

conflict_edges = client.get_edges(
    invitation='ICLR.cc/2020/Conference/-/Conflict',
    label='Personal',
    tail='~Test_User1',
    limit=10
)

Note that since conflict data is sensitive, you may not have permissions to access conflict edges mentioned in the above example.

By default, get_edges will return up to the first 1000 corresponding Edges (limit=1000). To retrieve Edges beyond the first 1000, you can adjust the offset parameter, or use the function get_all_edges which returns a list of all corresponding Edges:

conflict_edges_iterator = openreview.tools.iterget_edges(
    client,
    invitation='ICLR.cc/2020/Conference/Reviewers/-/Conflict',
    label='Personal',
    tail='~Test_User1'
)

Since edges usually are very large in numbers, it is possible to get just the count of edges by using the function client.get_edges_count. Note that this only returns the count of edges visible to you.

conflict_edges_count = client.get_edges_count(
    invitation='ICLR.cc/2020/Conference/Reviewers/-/Conflict',
    label='Personal'
)

Since most of the common tasks performed using Edges require Edges to be grouped, it’s also possible to query for already grouped Edges. Consider the following example that gets all reviewers grouped by papers they have conflicts with for the ICLR 2020 Conference.

Note that in this case it's not necessary to pass id, head or tail as parameters. This is the advantage of using the get_grouped_edges method.

grouped_conflict_edges = client.get_grouped_edges(
    invitation='ICLR.cc/2020/Conference/Reviewers/-/Conflict',
    groupby='head',
    select='tail,weight,label'
)

Consider the following example that gets all papers grouped by reviewers they are in conflict with for the ICLR 2020 Conference. It returns a list of lists of the {head, weight, label} of each conflict edge for that tail.

grouped_conflict_edges = client.get_grouped_edges(
    invitation='ICLR.cc/2020/Conference/Reviewers/-/Conflict',
    groupby='tail',
    select='head,weight,label'
)

To group Edges, one must already know what the edge.head and edge.tail represent in an Edge and that information can be seen from the Edge’s invitation.