{"id":113,"date":"2018-04-17T11:50:08","date_gmt":"2018-04-17T10:50:08","guid":{"rendered":"http:\/\/generic.wordpress.soton.ac.uk\/neighbourhood\/?p=113"},"modified":"2018-04-25T12:55:29","modified_gmt":"2018-04-25T11:55:29","slug":"graph-theory-edge-betweenness-for-target-marketing","status":"publish","type":"post","link":"https:\/\/generic.wordpress.soton.ac.uk\/neighbourhood\/2018\/04\/17\/graph-theory-edge-betweenness-for-target-marketing\/","title":{"rendered":"Graph theory: edge betweenness for target marketing"},"content":{"rendered":"<p>Graph theory provides a way of using graphs to represent networks, and is often used in the development and study of online social networks.<\/p>\n<p><img decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/n6-img-fp.akamaized.net\/free-vector\/3d-chemical-molecules_1284-3197.jpg?size=338&amp;ext=jpg\" \/><\/p>\n<p style=\"text-align: center\">Image source: <a href=\"https:\/\/www.freepik.com\/free-photos-vectors\/connected-users\">freepik<\/a><\/p>\n<p>At the core of graph theory is understanding the nature of connections, their relationship to one another, and calculating the importance of each node. &#8216;Importance&#8217; is calculated, in different ways, from the connections between individuals (or nodes) in the network.\u00a0In this post I will outline how\u00a0graph theory supports Neighbourhood&#8217;s marketing strategy.<\/p>\n<h2>The origins of Graph theory: connections across a city<\/h2>\n<p><img decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/www.maa.org\/sites\/default\/files\/images\/cms_upload\/Konigsberg_colour37936.jpg\" \/><\/p>\n<p style=\"text-align: center\">The origin of Graph theory:\u00a0<a href=\"https:\/\/www.maa.org\/press\/periodicals\/convergence\/leonard-eulers-solution-to-the-konigsberg-bridge-problem\">Leonard Euler&#8217;s Solution to the K\u00f6nigsberg Bridge Problem<\/a><\/p>\n<blockquote><p>&#8220;Graph theory was born in 1736 with Euler\u2019s solution [to] the K\u00f6nigsberg bridge problem, which asked whether it was possible to plan a walk over the seven bridges of the town without re-tracing one\u2019s steps. Euler realised that the problem could be rephrased in terms of a graph whose vertices corresponded to the four regions of the city, and whose edges corresponded to the seven bridges each joining a pair of the regions.&#8221;<\/p>\n<p style=\"text-align: right\"><a href=\"https:\/\/www.southampton.ac.uk\/courses\/modules\/math3033.page\">James\u00a0Anderson<\/a><\/p>\n<\/blockquote>\n<p>&nbsp;<\/p>\n<h2>Graph theory terminology<\/h2>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/mathinsight.org\/media\/image\/image\/small_undirected_network_labeled.png\" alt=\"Small undirected network with labeled nodes and edges\" width=\"387\" height=\"348\" \/><\/p>\n<p style=\"text-align: center\">Image source: <a href=\"https:\/\/mathinsight.org\/network_introduction\">Math insight<\/a><\/p>\n<p>First of all, a quick explanation of graph theory terminology:<\/p>\n<ul>\n<li><strong>Nodes:<\/strong> (also known as vertices) A node is a point on the network, for example in a social network, a node is a person<\/li>\n<li><strong>Edges:<\/strong> An edge is a connection (or link) between two nodes. May be directed (only go in one direction) or undirected<\/li>\n<\/ul>\n<h2>Edge betweenness<\/h2>\n<p>The edge betweenness of nodes in a network is calculated from how much traffic flows through its connecting edges. This establishes the level of connectivity between each node (or user), and all other nodes.<\/p>\n<p>The\u00a0<a href=\"http:\/\/www.pnas.org\/content\/99\/12\/7821\">Girvan-Newman method<\/a> or algorithm is often used to calculate this.\u00a0To help visualize the concept, this graph shows the nodes with the highest calculated betweenness centrality in blue:<\/p>\n<figure id=\"attachment_114\" aria-describedby=\"caption-attachment-114\" style=\"width: 391px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/generic.wordpress.soton.ac.uk\/neighbourhood\/wp-content\/uploads\/sites\/259\/2018\/04\/600px-Graph_betweenness.svg_.png\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-114\" src=\"http:\/\/generic.wordpress.soton.ac.uk\/neighbourhood\/wp-content\/uploads\/sites\/259\/2018\/04\/600px-Graph_betweenness.svg_.png\" alt=\"\" width=\"391\" height=\"391\" srcset=\"https:\/\/generic.wordpress.soton.ac.uk\/neighbourhood\/wp-content\/uploads\/sites\/259\/2018\/04\/600px-Graph_betweenness.svg_.png 600w, https:\/\/generic.wordpress.soton.ac.uk\/neighbourhood\/wp-content\/uploads\/sites\/259\/2018\/04\/600px-Graph_betweenness.svg_-150x150.png 150w, https:\/\/generic.wordpress.soton.ac.uk\/neighbourhood\/wp-content\/uploads\/sites\/259\/2018\/04\/600px-Graph_betweenness.svg_-300x300.png 300w\" sizes=\"auto, (max-width: 391px) 100vw, 391px\" \/><\/a><figcaption id=\"caption-attachment-114\" class=\"wp-caption-text\">Graph showing betweenness centrality, nodes with highest value are dark blue<\/figcaption><\/figure>\n<p>&nbsp;<\/p>\n<p style=\"text-align: center\">Image source:\u00a0<a href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Graph_betweenness.svg\">Claudio Rocchini<\/a><\/p>\n<h2>Edge betweenness\u00a0for target marketing<\/h2>\n<p>Neighbourhood is about connecting people to local opportunities to pursue their interests, which in turn connects them to other people in their neighbourhood.\u00a0Neighbourhood users which have high &#8216;betweenness&#8217; will be most likely to\u00a0help with:<\/p>\n<ul>\n<li>Increasing the number of activities and groups on Neighbourhood<\/li>\n<li>Spreading the word and increasing our user base with &#8216;high value&#8217; new users<\/li>\n<\/ul>\n<p>This is based upon the insight that <em>trust builds up quickly between individuals that share interests<\/em>. Meaning\u00a0the most connected, trusted users will invite the most valuable new users: those who are deeply engaged in mutual interests, and that enter the platform with a high level of trust in at least one existing user. These &#8216;high value&#8217; new users will be most likely to\u00a0play a key role in enriching <em>subhood<\/em> interest groups on Neigbhourhood.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter\" src=\"https:\/\/encrypted-tbn0.gstatic.com\/images?q=tbn:ANd9GcQcLepjc0RZpolHrs1tFdK-ZEYfhI9GU8_jKA4Y1N1k0h-ALWwD\" alt=\"Related image\" width=\"298\" height=\"298\" \/><\/p>\n<p style=\"text-align: center\">Image source:\u00a0<a href=\"http:\/\/www.icesi.edu.co\/marketingzone\/la-mutacion-poblacional\/\">Universidad Icesi<\/a><\/p>\n<p>An important pillar of our marketing strategy is friend-get-friend incentives, which encourage our users to invite others. For this we will identify Neighbourhood users who have high\u00a0Betweenness Centrality, and target them with personalized, extra incentives to start new activities and groups on Neighbourhood, and to invite new users.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Graph theory provides a way of using graphs to represent networks, and is often used in the development and study of online social networks. Image source: freepik At the core of graph theory is understanding the nature of connections, their relationship to one another, and calculating the importance of each &hellip;<\/p>\n","protected":false},"author":2944,"featured_media":191,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[17,3,18,2],"class_list":["post-113","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorised","tag-graph-theory","tag-interests","tag-marketing","tag-social-network"],"jetpack_featured_media_url":"https:\/\/generic.wordpress.soton.ac.uk\/neighbourhood\/wp-content\/uploads\/sites\/259\/2018\/04\/peoplebubbles.png","_links":{"self":[{"href":"https:\/\/generic.wordpress.soton.ac.uk\/neighbourhood\/wp-json\/wp\/v2\/posts\/113","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/generic.wordpress.soton.ac.uk\/neighbourhood\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/generic.wordpress.soton.ac.uk\/neighbourhood\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/generic.wordpress.soton.ac.uk\/neighbourhood\/wp-json\/wp\/v2\/users\/2944"}],"replies":[{"embeddable":true,"href":"https:\/\/generic.wordpress.soton.ac.uk\/neighbourhood\/wp-json\/wp\/v2\/comments?post=113"}],"version-history":[{"count":11,"href":"https:\/\/generic.wordpress.soton.ac.uk\/neighbourhood\/wp-json\/wp\/v2\/posts\/113\/revisions"}],"predecessor-version":[{"id":193,"href":"https:\/\/generic.wordpress.soton.ac.uk\/neighbourhood\/wp-json\/wp\/v2\/posts\/113\/revisions\/193"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/generic.wordpress.soton.ac.uk\/neighbourhood\/wp-json\/wp\/v2\/media\/191"}],"wp:attachment":[{"href":"https:\/\/generic.wordpress.soton.ac.uk\/neighbourhood\/wp-json\/wp\/v2\/media?parent=113"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/generic.wordpress.soton.ac.uk\/neighbourhood\/wp-json\/wp\/v2\/categories?post=113"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/generic.wordpress.soton.ac.uk\/neighbourhood\/wp-json\/wp\/v2\/tags?post=113"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}