George Kikuchi demos how Philadelphia Police Department uses R Shiny, visNetwork, DT, and leaflet to identify associations between crime suspects using sample data from Pulp Fiction PhillyR Meetup. Feb 21, 2018. Philadelphia, PA Follow PhillyR at https://www.linkedin.com/company/phillyr/ Join us for a meeting at https://www.meetup.com/PhillyR/

1. visNetwork, DT::datatable, leaflet
George Kikuchi

2. Problem
• Criminals often co-offend
• Cumbersome process to search multiple data
sources to identify co-offending patterns
• Mainframe-based system as the PPD users’
go-to resources

3. R Shiny Integration

4. Toy Data
• Relationship data from Pulp Fiction
• Co-appearance is defined as a linkage
– Sources:
• http://www.moviegalaxies.com
• https://la.curbed.com

5. Building Blocks
• Shiny
• Shinydashboard
• visNetwork
• DT datatable
• leaflet

6. Building Blocks
• Shiny
• Shinydashboard
• visNetwork
• DT datatable
• leaflet

8. Building Blocks
• Shiny
• Shinydashboard
• visNetwork
• DT datatable
• leaflet

9. Node and Edge

10. visNetwork(nodes, edges)

11. Building Blocks
• Shiny
• Shinydashboard
• visNetwork
• DT datatable
• leaflet

12. datatable(data.frame)

13. Building Blocks
• Shiny
• Shinydashboard
• visNetwork
• DT datatable
• leaflet

15. More functions, visualizations, and
interactivity
• Embedding a photo within datatable

16. More functions, visualizations, and
interactivity
• Hyperlinking visNetwork nodes (double-click)
visEvents(doubleClick = "function(properties) {
window.open('https://www.google.com/search?q=p
ulp+fiction+' +
this.body.data.nodes.get(properties.nodes[0]).id);}",

17. More functions, visualizations, and
interactivity
• Expanding a network through a click

18. • # selecting network elements
observe({
input$current_node_id
visNetworkProxy("network") %>%
visGetSelectedNodes()
})
• # react to a network element selection (e.g., left click a node)
observeEvent(input$network_selected, {
# insert additional data script here
visNetworkProxy("network") %>%
visUpdateNodes(nodes = nodes2) %>%
visUpdateEdges(edges = edges2)
})

19. More functions, visualizations, and
interactivity
• Linking visNetwork and data.table
Clicking a link (edge)
applies a filter to
data.table to get detail
information
subset(table.df, id %in% input$network_selectedEdges)