Ih

• Network


  A set of units (nerves, individuals, institutions, states), and a rule that defines whether, how, and to what extent any two units are tied to each other
• A network shows the relations that exist between nodes
• The same nodes can be simultaneously related to multiple networks with each network defined by a particular set of rules
• Hypernetwork or multiplex


  A set of networks that is made up of the same set of nodes
• Two types of networks

  • Relational Networks
  • Affiliation Networks
• Relational Networks


  Networks in which the rule that defines them describes the existence or absence, direction, and magnitude of a relationship between any two units
• Relational Networks


  • Neighborhood
  • Friendship
  • Alliance
  • Trade
• Affiliation Networks


  Networks in which the rule defines an affiliation of a unit with an event, organization, or group
• Affiliation Networks


  • Membership in a professional organization
  • Membership in an international organization
  • Distribution of the different provincial population based on their religion or ethnic affiliation
• Actors


  Discrete individual or collective units playing a role in a larger social system
• Ego network


  Made up of a focal actor or node called ego and the nodes to whom the ego is directly connected or linked
• The social units to whom the ego is connected are called alters
• Attributes that give additional information about the actors are called actor attributes
• First-order egonet


  Ego network that states the ties that exist between the alters
• Second-order egonet


  Ego network that shows the relationships between alters and other nodes in the network
• Connection


  The tie that links actors to one another
• Types of connections or ties

  • Behavioral interactions
  • Physical connections
  • Association or affiliation
  • Evaluation of one person by another person
  • Formal relations
• Dyad


  The basic unit of social networks made up of a pair of actors
• Dyad social network


  • A child who wishes to form friendship ties with another child
  • A store manager consults with his assistant manager
  • The Philippines wants to form an alliance with another country in the Southeast Asian region
• Triad


  When three actors are involved
• Triad social network


  • A child who wishes to form friendship ties with two other children
  • A store manager consults with his assistant manager and store supervisor
  • The Philippines wants to form an alliance with two other countries in the Southeast Asian region
• Relationship


  A collection of ties of a specific kind measured on pairs of actors from a particular group of social entities
• Social network


  A subset of nodes that are organized through their ties with each other
• Essential elements of social networks

  • Set of actors
  • Every actor has a set of individual attributes
  • It has a set of ties or connections that define at least one relation among actors
• The example on the immediate family of Jimson is a social network
• Neural network


  An interconnected assembly of simple processing elements, units or nodes, whose functionality is loosely based on the animal neuron
• The processing ability of a neural network is stored in the inter unit connection strengths, or weights, obtained by a process of adaptation to, or learning from, a set of training patterns
• A neural network can be likened to the brain in two ways: 1) Knowledge is acquired by the network from its environment through a learning process, and 2) Interneuron connection strengths, known as synaptic weights, store the acquired knowledge
• The human brain is a biological neural network made up of an interconnected web of neurons transmitting elaborate patterns of electrical signals
• The human nervous system can be considered as a three-staged system: 1) The human brain is the center, 2) It is represented by the neural or nerve net which acts as the receiver of information called stimulus, and 3) It perceives the information gathered and makes appropriate decisions to the stimulus
• The receptors translate the stimuli from the human body or any external environment into electric impulses that relay the information to the neural net or the brain, and the effectors convert the electric impulses produced by the neural net into visible responses as system outputs
• The brain has small scale and a large scale anatomical organizations wherein different functions take place at lower and higher levels, from synapses to neural microcircuits, dendritic trees, neurons, local circuits, and interregional circuits
• Neural networks are software simulations that behave as though they're built from billions of highly interconnected brain cells working in parallel, but they are not actual brains
• The most common example of artificial neural network consists of three groups or layers of units: input layer, hidden layer, and output layer
• Characteristics of neural networks

  • Processes information like the human brain
  • Is a "connectionist" computational system
  • Has the ability to learn
• Neural networks process information like the human brain, composed of a large number of highly interconnected processing elements (neurons) working in parallel to solve specific problems
• Neural networks are "connectionist" computational systems where information is processed collectively and in parallel throughout a network of nodes (neurons), unlike procedural programs that execute instructions in a linear manner
• Neural networks have the ability to learn from their environment and store the acquired knowledge in the connection strengths between the neurons