9.1 Load data

Regenerate data from previous chapter. (code below copied from previous chapter)

#read data
gss_url <-"https://raw.githubusercontent.com/mahoffman/stanford_networks/main/data/gss_local_nets.csv"
gss <- read_csv(gss_url) 

## Rows: 1426 Columns: 41
## ── Column specification ────────────────────────────────────────────────────────
## Delimiter: ","
## chr (13): sex, race, partyid, relig, educ2, educ3, educ4, educ5, relig1, rel...
## dbl (28): age, numgiven, close12, close13, close14, close15, close23, close2...
## 
## ℹ Use `spec()` to retrieve the full column specification for this data.
## ℹ Specify the column types or set `show_col_types = FALSE` to quiet this message.

#subset ties data
ties <- gss %>%
  dplyr::select(starts_with("close"))

#set zero links as missing links
ties[ties==0] <- NA
#repondents where all links among others are missing
others_missing <- rowSums(is.na(ties))==ncol(ties)
#remove any respondent that falls in any of the above
ties <- ties[!(others_missing),]

#make a function to generate a network of ties
make_ego_nets_simple <- function(tie){
  #get the all possible links among others
  tie <- tie %>% unlist
  #remove missing links
  tie <- tie[!is.na(tie)]
  #remove zero links
  tie <- tie[tie!=0]
  #get the identity of linked pairs
  others <- str_extract(names(tie), "[0-9]+")
  #split the linked others
  others_link <- str_split(others, "",simplify = TRUE) %>% as.data.frame
  #make edge list of others
  others_link <- cbind(others_link, tie)
  #ego graph with 
  graph_from_data_frame(others_link,
                        directed=FALSE)
}
#get all graphs
ego_nets_simple <- apply(ties,1,make_ego_nets_simple)
#
ties[1,]

## # A tibble: 1 × 10
##   close12 close13 close14 close15 close23 close24 close25 close34 close35
##     <dbl>   <dbl>   <dbl>   <dbl>   <dbl>   <dbl>   <dbl>   <dbl>   <dbl>
## 1       1       2      NA      NA       2       2      NA       1      NA
## # ℹ 1 more variable: close45 <dbl>

plot(ego_nets_simple[[1]])