# Visualising changes in many-to-one (directional) relationships (votes) between a set of objects over time

I have a set of objects, each of which can be assigned to another object within the set in a many-to-one, directional assignment, like a vote. Objects cannot be assigned to themselves reflexively, but they can be in an unassigned state ("not voting"). So for example, the set {A, ..., Z} plus relation could be in the following state:

A -> E
E -> C
B -> C
C -> B
D -> Y
{F, ..., Z} are not voting.


This state will change over time, in discrete steps, one vote at a time. For example, at time t = 0 the set could be as above. Then at t = 1, Z votes for C (Z -> C), resulting in the state:

A -> E
E -> C
B -> C
C -> B
D -> Y
Z -> C
{F, ..., Y} are unassigned.


Can anyone come up with a neat way to illustrate graphically this set and the state changes over time? Ideally, it should be evident at a glance

• How many votes there are for one object at a given time.
• Which objects are voting for another given object.

Thanks!

• How many objects will be in the set? How many objects will receive votes, how many will receive a considerable amount of votes? Are votes eternal, or can they be retracted or changed? Sep 13, 2014 at 12:01
• There will generally only be between 10 and 50 objects in the set. Any object can be voted for, but the number of votes is obviously limited to the number of objects (1 vote per). Votes can be retracted and changed. Sep 15, 2014 at 7:48

## 1 Answer

Depending on the quantities, a sequence of bar charts may work. Here are two mock-ups. In the first the voters are identified by color. In the second, the voters are identified with labels and color is used to show deltas (add=purple and subtract=gray). Labels are harder to track from frame to frame than colors, but assigning unique colors doesn't scale well.

• Thanks! I like how easy it is to track new and retracted votes in the second solution. Sep 26, 2014 at 13:55