Some Definitions
The areas of Social Complexity and Computational Social Science employ words and phrases that are not always familiar to those not actively engaged in either area. Following is a list of some commonly used acronyms, words, and phrases, and their definitions. Most of these definitions are taken from the text Computational Social Science, Claudio Cioffi-Revilla, Springer, 2014; others are taken from Webster’s or Wikipedia. If you have suggestions for other terms that could be added to this list, please contact us .
| A | B | C | D | E | F | G |
| H | I | J | K | L | M | N |
| O | P | Q | R | S | T | U |
| V | W | X | Y | Z |
A
ABM (agent-based model): computational program that simulates the actions and interactions of discrete agents – manmade such as conflict; natural such as rainfall; geographical such as rivers or mountains; and human behavior – in order to observe the complex events that can result from various configurations of those agents; an object- oriented computational model for analyzing a social system.
Adaptation : the process of changing to fit some purpose or situation; the process of adapting
Agent: a person or thing that causes something to happen
AI (artificial intelligence): machines and software with the ability to perceive their environment and respond to it in in appropriate ways; technology and science that study and develop intelligent machines and software
Algorithm: a computable set of steps to achieve a desired result.
Array: a systematic arrangement of objects, usually in rows and columns.
Artifact: any object made by human beings, especially with a view to subsequent use.
Attribute: in CSS, a feature, variable, or parameter that characterizes a social entity; attributes are familiar concepts in Social Science, often under the name of “variables” or “parameters.”
B
Bayesian inference: derived from Bayes’ theorem (alternatively Bayes’ law or Bayes’ rule, also written as Bayes’s theorem), which describes the probability of an event, based on prior knowledge of conditions that might be related to the event. For example, if cancer is related to age, then, using Bayes’ theorem, a person’s age can be used to more accurately assess the probability that they have cancer, compared to the assessment of the probability of cancer made without knowledge of the person’s age. (see Frequentist inference)
Big Data: large quantities of social raw data that have recently become available through media such as mobile phone calls, text messaging, and other “social media,” remote sensing, video, and audio.
Boolean: Pertaining to or being a deductive logical system, as Boolean algebra, used to represent symbolically the relationships between sets, classes, and other entities. Named after George Boole, English mathemetician and logician (1815-64). Other systems, such as string or integer, are defined in this list.
C
CA (cellular automaton model): an object-oriented computational model for analyzing complex systems consisting of neighboring entities called cells, that change their state as they interact in a (typically two-dimensional) grid-like landscape.
Carneiro’s Theory of Circumscription : a theory of the role of warfare in state formation created by anthropologist Robert Carneiro (1927- ). The theory has been summarized in one sentence by Schacht: “In areas of circumscribed agricultural land, population pressure led to warfare that resulted in the evolution of the state.” The more circumscribed is an agricultural area, Carneiro argues, the sooner it politically unifies. (Wikipedia)
CAS(complex adaptive system): a system that changes its state, including its social structure and processes, in response to changing conditions. Adaptation in social systems is best seen as a multi-stage process, not as a single event. First, the system, or the actors within the system, must be aware that there is a need to adapt. Second, there must be an intent to adapt. Third, there must be capacity to adapt. Finally, adaptive behavior must be implemented in some form. If adaptation is successful, the system (a person, a family, a group, an economy, an entire society, a whole nation, or even a global society) endures; if it is not, the system is altered or fails.
Catastrophe Theory
Cell: A cell is a tile-like object defined by attributes and located 396 adjacent to other, similar objects. The state of a cell is given by its attribute values, 397 where one or more attribute is a function of the state of neighbors.
CDI: cyber-enabled discovery and innovation
Chaco Canyon and Cahokia: Chaco Canyon in New Mexico and Cahokia in Illinois were the most complex polities in the US before the European invasion.
Chiefdom: a form of hierarchical political organization in non-industrial societies usually based on kinship, and in which formal leadership is monopolized by the legitimate senior members of select families or “houses.” Chiefs lead because of their ascribed status, not their achieved status.
- Simple Chiefdom: a simple chiefdom is generally composed of a central community surrounded by or near a number of smaller subsidiary communities. All of the communities recognize the authority of a single kin group or individual with hereditary centralized power, dwelling in the primary community. Each community will have its own leaders, which are usually in a tributary and/or subservient relationship to the ruling elite of the primary community. (Wikipedia)
- Complex Chiefdom: a complex chiefdom is a group of simple chiefdoms controlled by a single paramount center, and ruled by a paramount chief. Complex chiefdoms have two or even three tiers of political hierarchy. Nobles are clearly distinct from commoners and do not usually engage in any form of agricultural production. The higher members of society consume most of the goods that are passed up the hierarchy as a tribute. (Wikipedia)
Chiefdom-a priori knowledge: before the formation of even the simplest chiefdom, people would need:
- Kinship knowledge: People had knowledge of their kin, which supported extended households beyond a family nucleus, as well as collective action based on deontic (obligation-based) norms or for advancing other goals.
- Communicative ability: Humans began using language to communicate between ca. 100,000 and 50,000 years ago. Communicative ability was necessary for collective action (both planning and execution), such as in large-scale hunting.
- Normative sociality: Cooperative social norms were known to people in pre- complex societies via biological evolution, specifically norms of kin selection and reciprocal altruism.
- Social identification ability: The ability to classify others into in-group vs. out- group status was essential for detecting potential threats and opportunities, as well as for norm use or invocation. In-out group identification generated cognitive complexity and balancing.
- Environmental knowledge: Awareness concerning the biophysical landscape was necessary for finding resources and detecting significant change, such as in local species, “normal” climate, and other aspects.
- Knowledge of normal vs. rare events: Ability to detect situational change, such as emergent threats or opportunities, beyond the biophysical environment, was necessary for assigning levels of urgency, significance, or priority.
- Food procurement ability: Hunting, gathering, fishing, herding, farming, or preying on others (stealing) was necessary for maintaining sustenance through- out seasons of the year and longer time spans, especially in temperate regions far from the Equator, where seasonal variations determine the basic food supply.
- Homicidal ability: Originally derived from the hunting skill-set, homicidal abil- ity was a necessity in some modes of collective action (while remaining a tabu among group members), such as when facing lethally aggressive adversaries. Deterrence also requires credible homicidal action.
- Collective action ability: People knew how to organize for collective action (i.e., how to lead and how to follow, and other modes of collective action) before chiefdoms formed. Collective action was invented and perfected through ancient activities such as hunting large mammals.
Compiler: A computer’s CPU (Central Processing Unit) understands only its own machine language. A compiler is a program that literally translates source code written in a high-level programming language (e.g., Fortran, C++, Pascal, Python) into machine code that is specific to and executed by the computer’s CPU.
Computational Social Science (CSS): the interdisciplinary investigation of the social universe on many scales, ranging from individual actors to the largest grouping, through the medium of computation.
Computer Language: a structured, formal grammar for communicating with and controlling what a computer does. Like all languages, including mathematical structures used by social scientists, computer languages consist of:
- Syntax: the proper rules for writing instructions; the correct sentences of a properly written program
- Semantics: the meaning of symbols; i.e., what various code elements stand for
- Pragmatics: the primary purpose, function, or paradigmatic orientation of a language
Coupled system:
D
DARPA (Defense Advanced Research Projects Agency): an agency of the United States Department of Defense responsible for the development of new technologies for use by the military; focuses on short-term (two to four year) projects run by small, purpose-built teams; founded in late 50s in response to Soviet “sputnik” success.
Data Mining: Data Mining is an analytic process designed to explore data (usually large amounts of data, also known as “big data”) in search of consistent patterns and/or systematic relationships between variables, and then to validate the findings by applying the detected patterns to new subsets of data. The ultimate goal of data mining is prediction.
Data Structure: Refers to the various ways in which data are organized for purposes of computation. Sometimes the same information is organized in different ways, so it will be structured differently, depending on computational need. There are many forms of data structures, such as:
- Array: has elements of the same type accessible by some index
- Bag: a set of values that can contain duplicates
- Queue: a list of items where the head item is accessed first; also known as a FIFO (first-in-first-out) list
- Set: a collection of elements in no particular order and each element occurs only once
- Stack: a data structure consisting of an ordered list of data such that the datum inserted last gets drawn first
- Tree: a data structure consisting of a root element with subtrees branching out to terminal nodes called leaves
- Graph: a generalization or extension of a “tree,” in which nodes and links (aka arcs or edges) can be arranged in any way
- Hash table: a structure in which values and keys are assigned by a function, called the hash function; aka “dictionary”
Debugging: Debugging is a methodical process of finding and reducing the number of bugs, or defects, in a computer program or a piece of electronic hardware, thus making it behave as expected.
Decomposability: degree to which entity will break down or be broken down into simpler parts or substances
DTRA:Defense Threat Reduction Agency
E
Endogenous: having an internal cause or origin.
Exogenous: relating to or developing from external factors.
Explanandum/explanans: explanandum is something that requires explaining, and explanans is the explanation. For example, if the presence of smoke is considered the phenomenon that requires explanation (explanandum), the statement “There is a fire” would provide the answer, or the explanans.
F
FIFO (first-in-first-out): describes data organization wherein the oldest entry is processed first
FILO (first-in-last-out): describes data organization wherein the oldest entry is processed last
FORTRAN: The word is derived from Formula Translating System, and is the name of a general-purpose programming language that is especially suited to numeric computation and scientific computing. Originally developed by IBM in the 1950s for scientific and engineering applications, Fortran has been in continuous use for over half a century in areas such as numerical weather prediction, finite element analysis, computational fluid dynamics, computational physics, and computational chemistry.
Fractal: a natural phenomenon or a mathematical set that exhibits a repeating pattern that displays at every scale; infinitely complex patterns that are self-similar across different scales; created by repeating a simple process over and over in an ongoing feedback loop.
Frequentist inference: a type of statistical inference that draws conclusions from sample data by emphasizing the frequency or proportion of the data; an alternative name is frequentist statistics. (Compare with Bayesian inference.)
G
GDELT (Global Data on Events, Location, and Tone): GDELT is an initiative to construct a catalog of human societal-scale behavior and beliefs across all countries of the world over the last two centuries down to the city level globally, to make all of this data freely available for open research, and to provide daily updates to create the first “realtime social sciences earth observatory (definition from GDELT website at http://gdelt.utdallas.edu/). The GDELT team currently consists of Kalev Leetaru of the University of Illinois, Philip Schrodt of Penn State (PSU), and Patrick Brandt of the University of Texas at Dallas (UTD).
Geodesic: the shortest line between two points on a sphere or other curved surface.
GeoMASON : an optional extension to MASON (see below) that provides geospatial support.
GIS (Geographic Information System): a system designed to capture, store, manipulate, analyze, manage, and present all types of spatial or geographical data.
H
HRAF (Human Relations Area Files): HRAF is a nonprofit international membership organization with over 300 member institutions in the U.S. and more than 20 other countries. It is a financially autonomous research agency based at Yale University, New Haven, CT, since 1949, its mission to encourage and facilitate worldwide comparative studies of human culture, society, and behavior in the past and present. It mainly pursues this mission by producing and distributing two full-text databases on the Web, eHRAF World Cultures (formerly “eHRAF Collection of Ethnography”) and eHRAF Archaeology (formerly eHRAF Collection of Archaeology”). HRAF also sponsors and edits the quarterly journal, Cross-Cultural Research: The Journal of Comparative Social Science, and organizes and edits encyclopedias.
The two eHRAF databases on the Web are accessible to people at HRAF member institutions. Expanded and updated annually, eHRAF World Cultures includes materials on cultures, past and present, all over the world. (The entire HRAF Collection, in paper, microfiche, and on the Web, covers nearly 400 cultures.) The second database, eHRAF Archaeology, has been building solely in electronic format since 1999. Also expanding annually, this database covers major archaeological traditions and many more sub-traditions and sites around the world. (Wikipedia)
I
IBM: individual-based modeling
Integer: a number that can be written without a fractional component; eg, positive or negative whole numbers (1 or -1, 33 or -33, etc), but NOT 9.75, 5½, or √2.
J
JAR file: In software, JAR (Java Archive) is a package file format typically used to aggregate many Java class files and associated metadata and resources (text, images, etc.) into one file to distribute application software or libraries on the Java platform.
K
Kin-based Network: Kinship networks are defined broadly as extended family, including biological relationships, genealogy, marriage, and other self-ascribed associations, beyond the family nucleus of parents and dependent children. (SAGE)
L
Latent Variable: a property that is measurable but not directly observable
LIFO (last-in-first-out): describes data organization wherein the newest entry is processed first
LILO (last-in-last-out): describes data organization wherein the newest entry is processed last
Lines of Evidence for detecting and measuring social complexity:
- Structural-the built environment, especially structures intended for public or collective use, such as temples, storehouses, fortifications, etc.
- Pictorial-imagery that depicts leaders, ceremonies, processions, etc.
- Epigraphic-written evidence such as inscriptions, chronicles, etc.
- Artifactual-something created by humans; item and its use speak to needs of that society re: survival (relationship with nature) or community (relationship with others)
- Forensic-human skeletal remains as they demonstrate burial practices, causes of death, dietary information, etc.
- Locational-settlement location as it suggests priorities of the group or exigencies that would have driven group activities–
Long Tail: In statistics, a long tail of some distributions of numbers is the portion of the distribution having a large number of occurrences far from the “head” or central part of the distribution. The distribution could involve popularities, random numbers of occurrences of events with various probabilities, etc.
List:
M
Marcus’s Dynamic Model
MAS (multi-agent system, or systems): a computerized system composed of multiple interacting intelligent agents within an environment; can be used to solve problems that are difficult or impossible for an individual agent or a monolithic system to solve.
MASON (multi-agent simulator of neighborhoods/networks): a Java-based simulation program developed by George Mason University and in wide use.
MDS (multi-dimensional scaling): a means of visualizing the level of similarity of individual cases of a dataset.
MIT: Massachusetts Institute of Technology
Models/Modeling:
- System Dynamics: an approach to understanding the nonlinear behavior of complex systems over time using stocks and flows, internal feedback loops and time delays.(Wikipedia)
- Equation-based: captures characteristics of a system by identifying system variables and describing the systems with equations that represent these variables.
- Queuing: queueing theory is the mathematical study of waiting lines, or queues; in queueing theory a model is constructed so that queue lengths and waiting time can be predicted.
- Object-based Orientation: a type of computer programming (software design) in which programmers define not only the data type of a data structure, but also the types of operations (functions) that can be applied to the data structure.
- Agent-based: An agent-based model (ABM) is one of a class of computational models for simulating the actions and interactions of autonomous agents (both individual or collective entities such as organizations or groups) with a view to assessing their effects on the system as a whole. (Wikipedia)
- Evolutionary
Moore Neighborhood: the eight cells surrounding a central cell on a two-dimensional square grid; named after Edward F. Moore, a pioneer of cellular automata theory.
MURI(multidisciplinary university research initiative): MURI is an acronym for a program of the Office of Naval Research that awards grants in research areas that are specified by participating government agencies.
N
NASA: National Aeronautics and Space Administration
Native code: Native code is computer programming (code) that is compiled to run with a particular processor and its set of instructions. If the same program is run on a computer with a different processor, software can be provided so that the computer emulates the original processor.
NATO: North Atlantic Treaty Organization
Node: a connection point, a redistribution point, or a communication endpoint (some terminal equipment); the definition of a node depends on the network and protocol layer referred to.
NSF: National Science Foundation
O
OCR (optical character recognition): the mechanical or electronic conversion of images of typewritten or printed text into machine-encoded text. It is widely used as a form of data entry from printed paper data records, whether passport documents, invoices, bank statements, computerized receipts, business cards, mail, printouts of static-data, or any suitable documentation. (Wikipedia)
ONR: Office of Naval Research
Ontology: the philosophical study of the nature of being, becoming, existence, or reality. (Wikipedia)
Orthogonal: intersecting or lying at right angles, or having perpendicular slopes or tangents at the point of intersection
P
PI (Principal Investigator): person in charge of managing a grant and leading the grant research team.
Political System a system of politics and government, similar to the legal system, economic system, cultural system, and other social systems.
Polity : a state or one of its subordinate civil authorities, such as a province, prefecture, county, municipality, city, or district; generally understood to mean a geographic area with a corresponding government. (Wikipedia)
Politogenesis : the scientific understanding of the origins of human social complexity
Power Law : In statistics, a power law is a functional relationship between two quantities, where one quantity varies as a power of another; for instance, the number of cities having a certain population size is found to vary as a power of the size of the population. (Wikipedia)
PPNB: pre-Pottery Neolithic B period, dated between ca. 10,700 and ca. 8,000 BP or 7000 – 6000 BCE.
Programming Language : a formal constructed language designed to communicate instructions to a machine, particularly a computer; programming languages can be used to create programs to control the behavior of a machine or to express algorithms. (Wikipedia)
Q
R
RAM (Random Access Memory): random access memory is a form of computer data storage; a random-access memory device allows data items to be read and written in approximately the same amount of time, regardless of the order in which data items are accessed, in contrast to other direct-access data storage media such as hard disks, CD-RWs, and DVD-RWs, where the time required to read and write data items varies depending on their physical locations on the recording medium. (Wikipedia)
Random Graph:
Random Network:
Rank-size Law/Rank-size Rule: rank-size distribution, or the rank-size rule (or law), describes the remarkable regularity in many phenomena, including the distribution of city sizes, the sizes of businesses, the sizes of particles (such as sand), the lengths of rivers, the frequencies of word usage, and wealth among individuals. (Wikipedia)
Recursion: a method where the solution to a problem depends on solutions to smaller instances of the same problem
Robotics: Robotics is the branch of mechanical engineering, electrical engineering and computer science that deals with the design, construction, operation, and application of robots, as well as computer systems for their control, sensory feedback, and information processing. (Wikipedia)
S
SAS: a software suite that can mine, alter, manage and retrieve data from a variety of sources and perform statistical analysis on it. SAS provides a graphical point-and-click user interface for non-technical users and more advanced options through the SAS programming language. (Wikipedia)
Scale-free Network: a network whose degree distribution follows a power law, at least asymptotically. (Wikipedia)
SD (system dynamics model): a variable- based computational model for analyzing complex systems containing feedback and feed- forward dependencies among variables and rates of change, often with high-dimensionality.
Sequence: in mathematics, a sequence is an ordered collection of objects in which repetitions are allowed. Like a set, it contains members (also called elements, or terms); the number of elements (possibly infinite) is called the length of the sequence. (Wikipedia)
SES (socioeconomic status): an economic and sociological combined total measure of a person’s work experience and of an individual’s or family’s economic and social position in relation to others, based on income, education, and occupation. (Wikipedia)
Set: a collection of distinct objects, considered as an object in its own right. For example, the numbers 2, 4, and 6 are distinct objects when considered separately, but when they are considered collectively they form a single set of size three, written {2,4,6}.
SI: Smithsonian Institution
Simon’s Theory of Artifacts and Social Complexity:
Simple Network:
Simulation Modeling: simulation modeling is the process of creating and analyzing a digital prototype of a physical model to predict its performance in the real world.
Single-scale Network:
SNA (social network analysis): the methodical analysis of social networks; social network analysis views social relationships in terms of network theory, consisting of nodes (representing individual actors within the network) and ties (which represent relationships between the individuals, such as friendship, kinship, organizational position, sexual relationships, etc.) — these networks are often depicted in a social network diagram, where nodes are represented as points and ties are represented as lines. (Wikipedia)
Social Complexity: the study of the phenomena of human existence and the many possible arrangements of relationships between those phenomena.
Social Network: A social network consists of several constituent parts which include entities (actors, values, sentiments, ideas, locations, attributes), relations (links, ties, associations, affiliations, interactions, evaluations), and aggregations (dyads, triads, groups, and subgroups).
Social Simulation: a research field that applies computational methods to study issues in the social sciences. Selected data regarding aspects of human behavior are integrated into a computer program written to predict and map likely outcomes of the behavior under study. Such studies can vary widely, from social interactions under specific circumstances, to survival of individuals or communities in the face of natural or manmade calamities.
Spatial-temporal Analysis: Spatial-temporal models arise when data are collected across time as well as space. A typical
example would be that of a monitoring network (of an atmospheric pollutant, say, or a network of meteorological stations) on which data are collected at regular intervals, say every day or every week. Thus the data analysis has to take account of spatial dependence among the monitors, but also that the observations at each monitor typically are not independent but form a time series. In other words, one must take account of temporal correlations as well as spatial correlations.
SPSS: SPSS is a widely used program for statistical analysis in social science. The software name originally stood for Statistical Package for the Social Sciences (SPSS), reflecting its original market, although it is now popular in other fields as well. The original SPSS manual (Nie, Bent & Hull, 1970) has been described as one of “sociology’s most influential books,” for allowing ordinary researchers to do their own statistical analysis. (Wikipedia)
State: A state is a polity with stratified and ranked society (elite members, civil servants, traders, military, and commoners), a system of government composed of specialized, differentiated institutions with authoritative decision-making, capacity to collect taxes as government revenue, and reliable control over territory and its resources.
State as Distinguished from Chiefdom: the following characteristics distinguish a State from a Chiefdom
- Public issues: Members of society who live in a state have an expectation that government policy will address public issues; this expectation generally increases over time, rather than decreases.
- Policymaking: Problem-solving to address public issues through policies is a formal, institutionalized process.
- Coalition: Rulers still depend on a support coalition, often called nobility, with side-payments provided to supporters, but on a scale greater than in chiefdoms.
- Taxation: Government operations are financed primarily by tax revenues extracted from commoners and merchants, as well as by the spoils of warfare
- Bureaucracy: The role of the system of public administration plays a critical role in the provision of public goods and in tracking state revenue streams.
- Cost of government operations: Maintaining a ruling elite that decides policy and a bureaucracy that implements it is a permanent, recurring cost that somehow must be financed.
- Private property: Right over private property is enforced by rule of law and judiciary institutions.
- Interdependencies: The state leader (now a king, as opposed to a paramount chief) depends on his ability to extract resources from the nobility in exchange for titles and rights, as well on the capacity of government to deliver an array public goods (defense, justice, public sanitation, policing, markets, roads, port facilities). Members of the nobility depend partly on the state leader for their livelihood and prestige, and partly on compliance from local commoners. In turn, commoners depend on members of the local nobility for policing, defense against aggressors, and for organizing other forms of collective action, including public works.
- Monumental structures: Large-scale monumental structures in states are created by paid and forced labor (including slaves, captives); these include construction of palaces and monumental tombs, road networks, aqueducts, military fortifications of many kinds (from sophisticated and massive city walls to regional frontier walls still visible from space), industrial factories (e.g., bronze, requiring complex supply chains and thousands of workers and specialized managers), among the most costly. Temples and spiritual structures are not neglected by the state; they are built bigger, since they are still perceived to provide rewards in the afterlife.
- Energy budget (energetics): Food production in a state polity is organized to yield surplus on a large scale, because the number of persons who are not producing food is a much greater proportion of the population.
- More public structures: A corollary of the above feature is the construction of non-residential office space in palaces to support operations of public adminis- tration, judicial courts, and military barracks and forts.
- Environmental conditions: The environment, including natural hazards in the state territory, has even greater significance, because of greater population size and increasingly complex infrastructure systems exposed to a broader spectrum of risks, some of them interdependent or “cascading,” linked via infrastructure.
- Precious stones, metals, textiles: Consumption of jewelry, all forms of elaborate ornaments, and sumptuous clothing by state elites (secular, military, and religious) is exuberant, compared to wares in chiefdoms; all of these must be financed.
- Military expenditures: The cost of a permanent, on-demand military force (personnel, armor, weapons, facilities) is a major component of a state budget.
Stochastic: The term stochastic occurs in a wide variety of professional or academic fields to describe events or systems that are unpredictable due to the influence of a random variable; researchers refer to physical systems in which they are uncertain about the values of parameters, measurements, expected input and disturbances as “stochastic systems.” (Wikipedia)
String: In computer programming, a string is traditionally a sequence of characters, generally understood as a data type and often implemented as an array of bytes (or words) that stores a sequence of elements, typically characters, using some character encoding. (Wikipedia)
Structural Validity:
Supply Chain Robotics: a linear array of sequential operations required to produce an end result. Complex societies (and even those that are not so complex) rely on supply chains of many different kinds to provide a vast array of goods and services.
Synergy: the interaction of multiple elements in a system to produce an effect different from or greater than the sum of their individual effects (Wikipedia); from the Greek word synergos συνέργια, meaning “working together.”
Synthetic population: represents individual actors in the form of households and household members; a synthetic population is statistically equivalent to a real population.
System Dynamics: System dynamics (SD) is a methodology and mathematical modeling technique for framing, understanding, and discussing complex issues and problems. (Wikipedia)
Systems Theory: the interdisciplinary study of systems in general, with the goal of elucidating principles that can be applied to all types of systems at all nesting levels in all fields of research.
T
Tessellation: A tessellation of a flat surface is the tiling of a plane using one or more geometric shapes, called tiles, with no overlaps and no gaps. In mathematics, tessellations can be generalized to higher dimensions and a variety of geometries. (Wikipedia)
Theory of Collective Action: The collective action theory was first published by Mancur Olson in 1965. He argues that any group of individuals attempting to provide a public good has troubles to do so efficiently. On the one hand individuals have incentives to “free-ride” on the efforts of others in certain groups and on the other hand the size of a group is of high importance and difficult to optimally determine. (Wikipedia)
Tuple: A tuple is a finite ordered list of elements.
U
UAV (unmanned autonomous vehicle, or also unmanned aerial vehicle): a vehicle without a person on board. Unmanned vehicles can either be remote controlled or remote guided vehicles, or they can be autonomous vehicles which are capable of sensing their environment and navigating on their own. (Wikipedia)
UML (Unified Modeling Language) : a standardized notational system for graphically representing complex systems consisting of classes, objects, associations among them, dynamic interactions, and other scientifically important features.
- Class Diagram: a type of static structure diagram that describes the structure of a system by showing the system’s classes, their attributes, operations (or methods), and the relationships among objects. (Wikipedia)
- Sequence Diagram: an interaction diagram that shows how processes operate with one another and what is their order; shows object interactions arranged in time sequence; depicts the objects and classes involved in the scenario and the sequence of messages exchanged between the objects needed to carry out the functionality of the scenario. (Wikipedia)
- State Diagram: a type of diagram used to describe the behavior of systems; requires that the system described is composed of a finite number of states, which is sometimes the case, while at other times it is a reasonable abstraction. (Wikipedia)
URL: URL is an acronym for Uniform Resource Locator and is a reference (an address) to a resource on the Internet. A typical URL has the form http://www.example.com/index.html, which indicates the protocol type (http), the domain name, (www.example.com), and the specific web page (index.html). (Wikipedia)
V
Von Neumann Neighborhood: the von Neumann neighborhood comprises the four cells orthogonally surrounding a central cell on a two-dimensional square lattice; named after John von Neumann, who used it to define the von Neumann cellular automaton and the von Neumann universal constructor within it. It is one of the two most commonly used neighborhood types for two-dimensional cellular automata, the other one being the 8-cell Moore neighborhood. (Wikipedia)
W
Watts-Strogatz Model: The Watts–Strogatz model is a random graph generation model that produces graphs with small-world properties, including short average path lengths and high clustering. It was proposed by Duncan J. Watts and Steven Strogatz in their joint 1998 Nature paper. (Wikipedia)
Weighted Network (aka Valued Network): a network where the ties among nodes have weights assigned to them. The elements of a system are represented as nodes (also known as actors or vertices) and the connections among interacting elements are known as ties, edges, arcs, or links. (Wikipedia)
Z
Zipf’s Law: an empirical law formulated using mathematical statistics, referring to the fact that many types of data studied in the physical and social sciences can be approximated with a Zipfian distribution, one of a family of related discrete power law probability distributions. The law is named after the American linguist George Kingsley Zipf (1902–1950), who popularized it and sought to explain it (Zipf 1935, 1949), though he did not claim to have originated it. (Wikipedia)
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