Overview
Resource allocation measurement assumes that a node send some resource to another node through their common neighbors playing the role of transmitters. In the simplest case, we assume that each transmitter has a unit of resource, and will averagely distribute it to all its neighbors. Thus the closeness of two nodes can be described by the size of resources one node sends to the other node. This is proposed by Tao Zhou、Linyuan Lü and Yi-Cheng Zhang in 2009:
- T. Zhou, L. Lü, Y. Zhang, Predicting Missing Links via Local Information (2009)
Basic Concept
Resource Allocation
After finding the common neighbors of two nodes, resource allocation measurement uses the sum of reciprocal of the number of neighbors of these common neighbors to determine the closeness of the two nodes, which is calculated by the following formula:
where N(x)
and N(y)
are neighbor sets of x
and y
respectively, u
is the common neighbor of x
and y
. The larger the value of RA(x,y)
is, the closer the two nodes are, value of 0 indicates that the two nodes are not close.
Taking the above graph as an example, the score of resource allocation of the blue and red node is the sum of the reciprocal of neighbors of the yellow and green node, which is 1/4 + 1/3 = 0.5833
.
Special Case
Lonely Node, Disconnected Graph
Lonely node does not have any neighbor node, the algorithm does not calculate the Resource Allocation between lonely node and any other node, either it considers the Resource Allocation of two nodes which are located in different connected components.
Self-loop Edge
The algorithm ignores all self-loop edges when calculating neighbor nodes.
Directed Edge
For directed edges, the algorithm ignores the direction of edges but calculates them as undirected edges.
Results and Statistics
Take the graph below as an example, run the algorithm in the graph:
Algorithm results: Calculate the Resource Allocation between node 3 and other nodes, return node1
, node2
and num
node1 | node2 | num |
---|---|---|
3 | 1 | 0.25 |
3 | 2 | 0.25 |
3 | 4 | 0.5833333333333333 |
3 | 5 | 0.5 |
3 | 6 | 0.25 |
3 | 7 | 0.3333333333333333 |
Algorithm statistics: N/A
Command and Configuration
- Command:
algo(topological_link_prediction)
- Configurations for the parameter
params()
:
Name |
Type |
Default |
Specification | Description |
---|---|---|---|---|
ids / uuids | []_id / []_uuid |
/ | Mandatory | IDs or UUIDs of the first set of nodes to be calculated, only need to configure one of them; every node in ids/uuids will be paired with every node in ids2/uuids2 for calculation |
ids2 / uuids2 | []_id / []_uuid |
/ | Mandatory | IDs or UUIDs of the second set of nodes to be calculated, only need to configure one of them; every node in ids/uuids will be paired with every node in ids2/uuids2 for calculation |
type | string | Adamic_Adar | Adamic_Adar / Common_Neighbors / Preferential_Attachment / Resource_Allocation / Total_Neighbors | Measurement of the closeness of the node pair; Adamic_Adar means to calculate AA index, Common_Neighbors means to calculate the number of common neighbors, Preferential_Attachment means to calculate the score of preferential attachment, Resource_Allocation means to calculate the score of resource allocation, Total_Neighbors means to calculate the number of total neighbors |
limit | int | -1 | >=-1 | Number of results to return; return all results if sets to -1 or not set |
Algorithm Execution
Task Writeback
1. File Writeback
Configuration | Data in Each Row |
---|---|
filename | node1 ,node2 ,num |
Example: Calculate the Resource Allocation of node UUID = 3 and all other nodes, write the algorithm results back to file named ra
algo(topological_link_prediction).params({
uuids: [3],
uuids2: [1,2,4,5,6,7],
type: "Resource_Allocation"
}).write({
file:{
filename: "ra"
}
})
2. Property Writeback
Not supported by this algorithm.
3. Statistics Writeback
This algorithm has no statistics.
Direct Return
Alias Ordinal | Type | Description |
Column Name |
---|---|---|---|
0 | []perNodePair | Closeness of node pair | node1 , node2 , num |
Example: Calculate the Resource Allocation of node UUID = 3 and UUID = 4, define algorithm results as alias named score and return the results
algo(topological_link_prediction).params({
uuids: [3],
uuids2: [4],
type: "Resource_Allocation"
}) as score
return score
Streaming Return
Alias Ordinal | Type | Description |
Column Name |
---|---|---|---|
0 | []perNodePair | Closeness of node pair | node1 , node2 , num |
Example: Calculate the Resource Allocation of node UUID = 1 and UUID = 5,6,7, return the results in the descending closeness score
algo(topological_link_prediction).params({
uuids: [1],
uuids2: [5,6,7],
type: "Resource_Allocation"
}).stream() as ra
return ra order by ra.num desc
Real-time Statistics
This algorithm has no statistics.