CIDnetworks and ScienceForums.Net

Alex Reinhart
February 27, 2014

Overview of SFN

Founded in 2002
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Reputation Points

The Network

CIDnetworks

CIDnetworks

Fits conditionally independent dyad models
- Latent spaces
- Latent vectors
- Stochastic blockmodels
- Sender-receiver
- Mixed membership stochastic blockmodels
- Hierarchical blockmodels
… plus covariates.

CID models

\[ g(\mathbb{E}[Y_{ij}]) = \beta_0 + X_{ij} \beta + U_{ij} + \epsilon_{ij} \]

\( Y_{ij} \): existence or value of tie
\( \beta_0 \): intercept
\( X_{ij} \): edge covariate matrix
\( \beta \): covariate slopes
\( U_{ij} \): latent structure

CID models

\( g \): link function:

Continuous outcome
Probit with cutoff
Probit with multiple cutoffs

Basic fitting

CID.Gibbs(rep.mat[,c("user1","user2")],
          components=list(LSM(2)),
          burnin=800, thin=10,
          draws=2000)

Latent space model

Latent space model

Latent space model

Latent vector model

Sender-receiver (beta) model