Add an interaction line to the edgelist
add_interaction.RdThe edgelist is a data frame containing information on the relationships between
actors, including the identities they inhabit in interactions with one another and
the labels they ascribe to each other. This function adds a line, representing a directed
relationship between one actor and another, to an edgelist data frame created by
blank_edgelist().
Arguments
- edgelist
interaction edgelist to add to
- agent
string agent's name
- object
string object's name
- agent_ident
string or string list: agent's label(s) for their own identity at the outset of an interaction. If multiple are provided, the agent chooses one of them, and the probability of each being chosen is taken from the agent_ident_prob argument. Default is c("friend", "person").
- agent_ident_prob
numeric or numeric list summing to 1: probability of taking each identity in agent_ident. Default is c(.5, .5).
- object_ident
string or string list: agent's label(s) for object's identity at the outset of an interaction. If multiple are provided, the agent chooses one of them, and the probability of each being chosen is taken from the object_ident_prob argument. Default is c("friend", "person").
- object_ident_prob
numeric or numeric list summing to 1: probability of taking each identity in object_ident. Default is c(.5, .5).
- institution
string or string list: the institution(s) identities in this relationship can come from. Valid institutions are lay, business, law, politics, academe, medicine, religion, family, sexual, monadic, group, corporal, male, and female (see actdata for details). Default is NA, which allows all institutions.
- rseed
an optional seed value to ensure identical simulation results with repeated runs.
Details
An edgelist line can be considered to define a relationship between two actors, an agent and an object, in a simulation from the perspective of the agent. The agent has a label (or multiple possible labels) for their own identity, and possible label(s) for the object's identity. If a list of multiple identities are provided for either agent or object, then the agent will randomly select one of the provided identities in each simulation repetition. In this case, the selection probabilities are given by agent_ident_prob and object_ident_prob.
Because each edgelist line represents the situation from the perspective of just one actor (the agent), each dyadic relationship in a simulation requires two edgelist lines: one from the perspective of each actor. Actors might agree on their identities--for example, both may agree that person 1 will act as a "sister" and person 2 will act as a "brother". In this case the two edgelist lines will be mirror images of each other. Actors may also begin interactions in disagreement about their identities--person 1 may see themselves as a "sister" and see person 2 as a "brother," but person 2 may instead see person 1 as a "bully" and themselves as a "victim."
It is possible that person 1 knows person 2 but person 2 does not know person 1. In this case, two edgelist lines are still required. However, the object_ident and object_ident_prob for person 2 (representing their initial label for person 1) will be the empty string "".
These identities are only starting points for a simulation. Identities may shift through the course of an interaction and generally may take any value represented in the identity dictionaries provided in the nodelist. If you wish to restrict the possible values, you may remove them from the dictionary provided there, or use the optional "institution" argument in this function to restrict to identities that only apply in particular social contexts.
If an interaction is given optional arguments (institution, rseed) that are not already columns in the provided dataframe, those columns are added.
Examples
edgelist <- blank_edgelist()
edgelist <- add_interaction(edgelist, agent = "Sally", object = "Reem",
agent_ident = "teacher", agent_ident_prob = 1,
object_ident = c("student", "troublemaker"), object_ident_prob = c(.8, .2))
edgelist <- add_interaction(edgelist, agent = "Reem", object = "Sally",
agent_ident = c("student", "teenager"), agent_ident_prob = c(.3, .7),
object_ident = "bore", object_ident_prob = 1)
edgelist <- add_interaction(edgelist, agent = "Jamal", object = "Sam",
agent_ident = "boss", agent_ident_prob = 1,
object_ident = c("employee", "friend", "do_nothing"), object_ident_prob = c(.5, .25, .25),
institution = "business")
edgelist <- add_interaction(edgelist, agent = "Sam", object = "Jamal",
agent_ident = "employee", agent_ident_prob = 1,
object_ident = "", object_ident_prob = "",
institution = "business")