goldfish

Description

The {goldfish} package offers a collection of tools designed for applying statistical models to dynamic network data. It primarily focus on models for relational event data, namely, sequences of interactions between actors or entities within a network, enriched by fine-grained time-stamps information. Relational event data emerge in various domains, such as automatically collected data about interactions in communication and social media research, social science studies using social sensors, and archival network studies that provide in-depth details regarding the timing or sequence of relational actions between nodes.

Currently, the package includes the following models:

• Dynamic Network Actor Models (DyNAM): Investigate relational event models as an actor-oriented decision process.
  • rate: Actors compete for creating the next relational event (Hollway 2020)
  • choice: The active actor chooses the receiver of the event from among the same (Stadtfeld and Block 2017) or a different set of nodes (Haunss and Hollway 2023)
  • choice_coordination: The creation of coordination ties as a two-sided process (Stadtfeld, Hollway, and Block 2017a)
• Dynamic Network Actor Models for interactions (DyNAMi): Investigate dynamics of conversation groups and interpersonal interaction in different social contexts from an actor-oriented perspective (Hoffman et al. 2020)
  • rate: Actors compete for joining or leaving groups
  • choice: The active actor choose the group to join
• Relational Event Models (REM): Investigate relational event models as a tie-oriented process (Butts 2008), taking into account right-censoring (Stadtfeld, Hollway, and Block 2017b).

Vignettes

For detailed documentation on each model, including usage examples, users are encouraged to consult the package’s vignettes and help files:

• Getting Started with goldfish (DyNAM and REM)
• Coordination ties (DyNAM-choice coordination)
• Face to face interactions (DyNAMi)
• Catalog of available effects

Table of Contents

• Installation
• Usage
  • Define data objects and link events
  • Define dependent events
  • Model specification and estimation
• About
• References

Installation

You can install {goldfish} directly from CRAN:

install.packages("goldfish")

To install the development version from GitHub, use the remotes package:

• For latest stable version: remotes::install_github("stocnet/goldfish", build_vignettes = TRUE)
• For latest development version: remotes::install_github("stocnet/goldfish@develop", build_vignettes = TRUE)

Or by downloading and install the latest binary releases for all major OSes – Windows, Mac, and Linux – can be found here.

Usage

Below is a quick-start guide to using the {goldfish} package. The dataset used in this example is an abbreviated version of the MIT Social Evolution data (?Social_Evolution).

Define data objects and link events

The main data objects required for the analysis are the node set(s) defineNodes() and network(s) defineNetwork(). The node set object contains labels and attributes of the actors in the network. In contrast, a network object contains the information of past relational events between actors. By default, defineNetwork() constructs an empty matrix, its dimensions defined by the length of the nodeset(s). Data frames containing event data that modify these data objects can be linked to them using the linkEvents() method.

library(goldfish)
data("Social_Evolution")

callNetwork <- defineNetwork(nodes = actors, directed = TRUE) |> # 1
  linkEvents(changeEvent = calls, nodes = actors) # 2

The events data frame, which indicates the time-varying attributes in the node set, contains the following columns:

• time: The time when the attribute changes, either a numeric or POSIXct value.
• node: The node for which the attribute changes, a character value that matches the label variable in the node set.
• replace: The new value of the attribute, a numeric value.

The events data frame that details the relational events between actors contains the following columns:

• time: The time when the event occurred, either a numeric or POSIXct value.
• sender: The actor initiating the event, a character value that matches the label variable in the node set.
• receiver: The actor receiving the event, a character value that matches the label variable in the node set.
• increment or replace: A numeric value indicating either the increment that the relational event represents or the new value.

Define dependent events

The final step in defining the data objects is to identify the dependent events. Here we would like to model as the dependent variable the calls between individuals. We specify the event data frame and the node set.

callsDependent <- defineDependentEvents(
  events = calls, nodes = actors,
  defaultNetwork = callNetwork
  )

Model specification and estimation

We specify our model using the standard R formula format like:

goldfish_dependent ~ effects(process_state_element)

We can see which effects are currently available and how to specify them here:

vignette("goldfishEffects")

Now to estimate this model, we use the ?estimate function.

mod00Rate <- estimate(
  callsDependent ~ indeg + outdeg,
  model = "DyNAM", subModel = "rate"
)

summary(mod00Rate)
#> 
#> Call:
#> estimate(x = callsDependent ~ indeg + outdeg, model = "DyNAM", 
#>     subModel = "rate")
#> 
#> 
#> Coefficients:
#>        Estimate Std. Error z-value  Pr(>|z|)    
#> indeg  0.551445   0.066344  8.3119 < 2.2e-16 ***
#> outdeg 0.263784   0.028386  9.2927 < 2.2e-16 ***
#> ---
#> Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
#> 
#>   Converged with max abs. score of 2e-05 
#>   Log-Likelihood: -1750.9
#>   AIC:  3505.8 
#>   AICc: 3505.9 
#>   BIC:  3514 
#>   model: "DyNAM" subModel: "rate"

mod00Choice <- estimate(
  callsDependent ~ inertia + recip + trans,
  model = "DyNAM", subModel = "choice"
)
summary(mod00Choice)
#> 
#> Call:
#> estimate(x = callsDependent ~ inertia + recip + trans, model = "DyNAM", 
#>     subModel = "choice")
#> 
#> 
#> Coefficients:
#>         Estimate Std. Error z-value  Pr(>|z|)    
#> inertia  5.19690    0.17397 29.8725 < 2.2e-16 ***
#> recip    1.39802    0.17300  8.0812 6.661e-16 ***
#> trans   -0.23036    0.21554 -1.0687    0.2852    
#> ---
#> Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1
#> 
#>   Converged with max abs. score of 7e-05 
#>   Log-Likelihood: -696.72
#>   AIC:  1399.4 
#>   AICc: 1399.5 
#>   BIC:  1411.7 
#>   model: "DyNAM" subModel: "choice"

About

This project is a joint collaboration between the Social Networks Lab at ETH Zürich and the Geneva Graduate Institute, and incorporates and supports several sub-projects.

References

Butts, Carter. 2008. “A Relational Event Framework for Social Action.” Sociological Methodology 38 (1): 155–200.

Haunss, Sebastian, and James Hollway. 2023. “Multimodal Mechanisms of Political Discourse Dynamics and the Case of Germany’s Nuclear Energy Phase-Out.” Network Science 11 (2): 205–23. https://doi.org/10.1017/nws.2022.31.

Hoffman, Marion, Per Block, Timon Elmer, and Christoph Stadtfeld. 2020. “A Model for the Dynamics of Face-to-Face Interactions in Social Groups.” Network Science 8 (S1): S4–25. https://doi.org/10.1017/nws.2020.3.

Hollway, James. 2020. “Network Embeddedness and the Rate of Water Cooperation and Conflict.” In Networks in Water Governance, edited by Manuel Fischer and Karin Ingold, 87–113. Cham: Palgrave MacMillan. https://doi.org/10.1007/978-3-030-46769-2_4.

Stadtfeld, Christoph, and Per Block. 2017. “Interactions, Actors, and Time: Dynamic Network Actor Models for Relational Events.” Sociological Science 4 (14): 318–52. https://doi.org/10.15195/v4.a14.

Stadtfeld, Christoph, James Hollway, and Per Block. 2017a. “Dynamic Network Actor Models: Investigating Coordination Ties Through Time.” Sociological Methodology 47 (1): 1–40. https://doi.org/10.1177/0081175017709295.

———. 2017b. “Rejoinder: DyNAMs and the Grounds for Actor-oriented Network Event Models.” Sociological Methodology 47 (1): 56–67. https://doi.org/10.1177/0081175017733457.