defineGroups_interaction {goldfish}

To define the second mode of a DyNAM-i model

Description

This function create all objects necessary to the estimation of a DyNAM-i model model = "DyNAMi" from dyadic interaction records and an actor set. It first creates a nodeset for the second mode of the interaction network that will be modeled, i.e. the interaction groups set, and an event list that indicates when groups are present or not through time. It then creates a list of interaction events, between actors and groups, in which an actor either joins or leaves a group. It is decomposed in an list of dependent events (that should be modeled) and a list of exogenous events (that should not be modeled). For example when an actor leaves a group and joins her own singleton group, only the leaving event is modeled but not the joining one, and vice versa when an actor belonging to a singleton group joins another group.

Usage

defineGroups_interaction(
  records,
  actors,
  seed.randomization,
  progress = getOption("progress")
)

Arguments

records

an object of class data.frame that is a list of rows of type node A, nodeB, Start, End, where nodeA and nodeB indicate the actors involved in a dyadic interaction, and Start and End indicating the starting and ending time of their interaction.

actors

a object of class nodes.goldfish that defines the actors interacting (labels in records and actors should be identical).

seed.randomization

an integer used whenever there should be some random choice to be made.

progress

logical weather detailed information of intermediate steps should be printed in the console.

Details

It is important to notice that sometimes some random decisions have to be made regarding who joined or left a group, for example when two actors start interacting but we do not know who initiated the interaction. Tot est for the robustness of such a procedure, one can use different randomization seeds and run the model several times.

Value

a list with the following data frames

interaction.updates

containing all joining and leaving events

groups

containing the nodeset corresponding to interaction groups (the second mode of the network)

dependent.events

for the events that should be modeled

exogenous.events

that are not modeled (for example when an actor leaves a group and joins its own singleton group, only the leaving event is modeled but not the joining event)

composition.changes

that is an events list that should be attached to the groups nodeset to indicate when a group is present or not