Social Network Analysis (SNA) is the process of investigating social structures through the use of network and graph theory. It is used to study interactions and relationships between individuals or organizations.
In this tutorial, we will learn how to perform basic social network analysis using PHP.
1. Installing Required Libraries
To begin, we need to install the required libraries. The most popular library for performing social network analysis in PHP is ‘Graphaware/Neo4j-php-client’. It provides a convenient way to interact with the Neo4j graph database.
To install the library, run the following command in your terminal:
composer require graphaware/neo4j-php-client
2. Setting up the Neo4j Database
Next, we need to set up a Neo4j database to store and analyze our social network data. You can download and install the Neo4j community edition from the official website.
After installing Neo4j, start the database server and access the Neo4j browser using the following URL: http://localhost:7474/browser
3. Creating the Graph Database
In the Neo4j browser, create a new database by running the following query:
CREATE DATABASE social_network
4. Connecting to the Neo4j Database
In your PHP script, you need to establish a connection with the Neo4j database. Use the following code snippet:
require_once ‘vendor/autoload.php’;
use GraphAware\Neo4j\Client\ClientBuilder;
$client = ClientBuilder::create()->addConnection(‘default’, ‘http://localhost:7474’)->build();
5. Creating Nodes and Relationships
Once connected, we can create nodes and relationships to represent our social network data.
To create a node, use the following code snippet:
$client->run(‘CREATE (user:User {name: “John”})’);
To create a relationship between two nodes, use the following code snippet:
$client->run(‘MATCH (user1:User {name: “John”}), (user2:User {name: “Jane”}) CREATE (user1)-[:FRIENDS]->(user2)’);
6. Querying the Graph Database
We can query the graph database to extract information about the social network.
To find all the users, use the following code snippet:
$result = $client->run(‘MATCH (user:User) RETURN user’);
To find the friends of a specific user, use the following code snippet:
$result = $client->run(‘MATCH (user:User {name: “John”})-[:FRIENDS]->(friend) RETURN friend’);
7. Analyzing the Social Network
We can analyze the social network using graph algorithms provided by Neo4j.
For example, to find the shortest path between two users, use the following code snippet:
$result = $client->run(‘MATCH (user1:User {name: “John”}), (user2:User {name: “Jane”})
CALL algo.shortestPath(user1, user2, “FRIENDS”, {direction: “OUTGOING”})
YIELD path
RETURN path’);
8. Displaying the Results
Finally, we can display the results of our social network analysis.
To display the users, use the following code snippet:
foreach($result->getRecords() as $record) {
$user = $record->get(‘user’);
echo $user->value(‘name’).”\n”;
}
To display the friends, use the following code snippet:
foreach($result->getRecords() as $record) {
$friend = $record->get(‘friend’);
echo $friend->value(‘name’).”\n”;
}
Conclusion
Social network analysis is a powerful tool for understanding relationships and interactions within a social network. With PHP and the Neo4j graph database, we can easily perform various social network analysis tasks.
By following this tutorial, you should now be able to perform basic social network analysis using PHP. You can further explore the functionality provided by Neo4j and the Graphaware/Neo4j-php-client library to analyze more complex social networks.