Difference between revisions of "Steve Hanneke and Eric Xing, Discrete Temporal Models of Social Networks"
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+ | == Estimation == | ||
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+ | θis the only unknown value in this model,this paper use MLE method to estimate the value of θ, in order to decrease the computation complexity, MCMC sampling is also used to estimate the approximate value of θ. The estimate algorithm is shown below | ||
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+ | [[File: Estimate_alg.jpg]] |
Revision as of 01:05, 28 March 2011
Citation
Steve Hanneke and Eric Xing, Discrete Temporal Models of Social Networks. Workshop on Statistical Network Analysis, held at the 23 rd International Conference on Machine Learning, 2006.
Online Version
Discrete Temporal Models of Social Networks
Datasets
The data involved in this example come from the United States 108th Senate, having n = 100 actors. Every time a proposal is made in the Senate, be it a bill, amendment, resolution, etc., a single Senator serves as the proposal’s sponsor and there may possibly be several cosponsors. Given records of all pro- posals voted on in the full Senate, this paper creates a sliding window of 100 consecutive proposals. For a particular placement of the window, this paper define a binary directed relation existing between two Senators if and only if one of them is a sponsor and the other a cosponsor for the same proposal within that window (where the direction is toward the sponsor)
Summary
This paper proposed a discrete temporal model family that is capable of modeling network evolution, while maintaining the flexibility of ERGMs. It also proposed such models to build upon ERGMs as much as possible. At first, this paper show us the simplest case of the proposed models before turning to the fully general models. Then this paper gives a general model and use MLE to estimate the parameter θ,which is the only unknown value in this model. The proposed model is also tested in order to prove its generality in practical work
Model Desprition
At first, this paper present some simple models to illustrate his point of view, which are shown below.
The four models above represent density, stability, reciprocity, and transitivity, respectively.
Then the transition of this model can be written as follows
By replacing A with general network N, then the general model can be written as follows:
Estimation
θis the only unknown value in this model,this paper use MLE method to estimate the value of θ, in order to decrease the computation complexity, MCMC sampling is also used to estimate the approximate value of θ. The estimate algorithm is shown below