DATAVIZFINAL

ggraph

Import packages

packages = c('igraph', 'tidygraph', 'ggraph', 'visNetwork', 'lubridate', 'tidyverse', 'knitr')

for(p in packages){library
  if(!require(p, character.only = T)){
    install.packages(p)
  }
  library(p, character.only = T)
}

Read datasets

GAStech_nodes <- read_csv("C:/Users/alexi/Documents/data/GAStech_email_node.csv")
GAStech_edges <- read_csv("C:/Users/alexi/Documents/data/GAStech_email_edge-v2.csv")

Transform data

GAStech_edges$SentDate  = dmy(GAStech_edges$SentDate)
GAStech_edges$Weekday = wday(GAStech_edges$SentDate, label = TRUE, abbr = FALSE)

GAStech_edges_aggregated <- GAStech_edges %>%
  filter(MainSubject == "Work related") %>%
  group_by(source, target, Weekday) %>%
    summarise(Weight = n()) %>%
  filter(source!=target) %>%
  filter(Weight > 1) %>%
  ungroup()
GAStech_edges_aggregated

## # A tibble: 1,456 x 4
##    source target Weekday   Weight
##     <dbl>  <dbl> <ord>      <int>
##  1      1      2 Monday         4
##  2      1      2 Tuesday        3
##  3      1      2 Wednesday      5
##  4      1      2 Friday         8
##  5      1      3 Monday         4
##  6      1      3 Tuesday        3
##  7      1      3 Wednesday      5
##  8      1      3 Friday         8
##  9      1      4 Monday         4
## 10      1      4 Tuesday        3
## # ... with 1,446 more rows

Replicate original graph

GAStech_graph <- tbl_graph(nodes = GAStech_nodes, edges = GAStech_edges_aggregated, directed = TRUE)

g <- GAStech_graph %>%
  mutate(betweenness_centrality = centrality_betweenness()) %>%
  mutate(closeness_centrality = centrality_closeness()) %>%
  ggraph(layout = "nicely") + 
  geom_edge_link(aes()) +
  geom_node_point(aes(colour = closeness_centrality, size=betweenness_centrality))

g + theme_graph() 

Task 1: Improve the code chunk used to create the organisation network graph by using the latest functions provided in ggraph2.0.

1. Formatting: node color & centrality color centrality color is difficult to ascertain due to full-black color and node color is indistinguishable due to gradient of the same color
2. Node label is missing, thus unable to identify which node belongs to which employee
3. Adding new information: department to provide a clearer overview of the departments of employees that they are networked to

Idea sketch

"insert graph here"

## [1] "insert graph here"

Implemented changes to graph

ggraph(GAStech_graph, layout="nicely") + 
  geom_node_voronoi(aes(fill = Department), max.radius = 0.2, colour = 'white',alpha=0.5) + 
  geom_edge_link(colour="grey") +
  geom_node_text(aes(label=label), repel=TRUE, size =2.5,colour="black")+
  scale_colour_gradientn(colours = rainbow(4))+
  geom_node_point(aes(size=centrality_betweenness(),colour=centrality_closeness()))+
  labs(title = "GAStech email network", colour="Closeness centrality", size="Betweenness centrality") +
  theme(legend.position = "right",
        legend.text = element_text(size = 8),
        legend.title = element_text(size = 11),
        legend.key.width = unit(2,"cm"),
        legend.key.height = unit(0.2,"cm"))

Visnetwork

Prepare object: aggregating and filtering of edges

GAStech_edges_aggregated <- GAStech_edges %>%
  left_join(GAStech_nodes, by = c("sourceLabel" = "label")) %>%
  rename(from = id) %>%
  left_join(GAStech_nodes, by = c("targetLabel" = "label")) %>%
  rename(to = id) %>%
  filter(MainSubject == "Work related") %>%
  group_by(from, to) %>%
    summarise(weight = n()) %>%
  filter(from!=to) %>%
  filter(weight > 1) %>%
  ungroup()

Rename to match visnetwork

GAStech_nodes <- GAStech_nodes %>%
  rename(group = Department)

Replicate original output

visNetwork(GAStech_nodes, GAStech_edges_aggregated) %>%
  visIgraphLayout(layout = "layout_with_fr") %>%
  visOptions(highlightNearest = TRUE, nodesIdSelection = TRUE)

With reference to the organisation network graph in Section 7.4 of Hands-on Exercise 10, you are required to complete the following tasks:

Task 2A:

• Improve the design of the graph by incorporating the following interactivity:
  • When a name is selected from the drop-down list, the corresponding node will not only be highlighted but also will be labelled. Furthermore, all the linked nodes of the selected node will also be labelled too.
    
  • When a node of the interactive graph is selected, the node will not only be highlighted but also will be labelled. Furthermore, all the linked nodes of the selected node will be labelled as well.

Improved design of graph

visNetwork(GAStech_nodes, GAStech_edges_aggregated, width = "100%") %>%
  visIgraphLayout(layout = "layout_with_fr") %>%
  visOptions(nodesIdSelection = TRUE, highlightNearest = list(enabled= TRUE, labelOnly = FALSE)) %>%
  visNodes(font = list(size=40))

Task 2B: Identify three aspects of the graph visualisation in Section 7.4 that can be improved.

1. Lack of legends and title: each node color is not known to users, which makes it difficult to comprehend which department they are from
2. User experience: view is easily altered by zoom-in/zoom-out functions, reset to default view is not available
3. Adding analytical tool: add filter option and tool tip this allows user to conduct second-level analysis by filtering department while the tool tip improves the overall information presented

Idea sketch

"insert sketch here"

## [1] "insert sketch here"

Implemented changes to graph

GAStech_nodes$title <- paste0("<p>Name:<br>",GAStech_nodes$label,"<p>Title:<br>",GAStech_nodes$Title,"<p>Group:<br>",GAStech_nodes$group)

visNetwork(GAStech_nodes, GAStech_edges_aggregated, main="GASTech email network", width = "100%") %>%
  visIgraphLayout(layout = "layout_with_fr") %>%
  visNodes(font = list(color="black",size=40)) %>%
  visOptions(highlightNearest = list(enabled = TRUE,labelOnly= FALSE, degree = 1, hover = TRUE),
    nodesIdSelection = TRUE,
    selectedBy = "group") %>%
  visLegend(zoom=FALSE) %>%
  visInteraction(dragView=FALSE,zoomView = TRUE,navigationButtons = TRUE, tooltipDelay = 120)