Modelling of Various Conditions and Factors
Computational simulation models can be used to investigate the developmental process of language evolution. For example, studies on the emergence of language modelled different linguistic environments and had individuals programmed with some factors in order to examine whether these factors and environments could lead to the development of certain linguistic aspects (eg. Vogt 2005). This ability to manipulate various factors and conditions also allows researchers to make a comparison of results brought about by the different factors and determine which of these are necessary for the development of language. In addition, the effects of isolated factors as well as effects of sets of factors on language evolution can be studied. For example, a study done on the Baldwin Effects on the development of language isolated two factors, learning cost and cultural variation, and studied their separate effects on language (Munroe & Cangelosi, 2002).
A Test for the Validity of Theories and Hypotheses
Computational simulation complements traditional study methods by acting as a validity test for theories and hypotheses founded on limited empirical findings or unreliable assumptions. By demonstrating how the theories and hypotheses work, computer simulation models can help researchers to identify problems in the theories and to modify them (Gong, 2009). This is especially important for previous theories which are often vague and were difficult to test empirically (Gong, 2009). Moreover, the building of the simulation models also aids researchers in ensuring that their theories are detailed and complete (Cangelosi & Parisi, 2002) as any inconsistencies in the theories will cause the models to malfunction and crash (Mareschal & Thomas, 2006).
The Study of Language as a Complex System
Language can be identified as a complex adaptive system (CAS) (Gong, 2009). A CAS can be understood as a very complex system where changes in the nature of some factors as well as their interactions can bring about higher order dynamics. This system is made up of a large number of factors arranged in a hierarchical structure which changes according to its environment. As such, language then is a CAS as it is similarly complex in nature and has an adaptive ability. Computational simulation, with its bottom-up approach, is an appropriate tool to study language as a CAS as it allows researchers to build simulation models based on several pre-determined factors and linguistic environments to observe how the interaction of these factors, as well as the interaction between the environment and linguistic factors could affect language evolution (Cangelosi & Parisi, 2002).
Fluid Construction Grammar
Languages work by the concept of “form and function pairings”. That is, the relationship between a word and its meaning is arbitrary; words have their meanings by virtue of us assigning such meanings to them. Hence, a word can take on a different meaning in different situations. One common example is as follows: the word form bank can mean the shore of a river and it can also mean the financial institution in which humans deposit their money for saving. Such meanings are also influenced by other aspects of language such as syntax, phonology, intonation and pragmatics. For example, if the word bank were to be stressed in conversation along with a rising tone, one could convey incredulity at a situation. In other words, the form of a word is essentially a sign packaged up as necessary for various purposes (Schneider & Tsarfaty, 2013).
Construction grammar is a formalised term for language models which represent all pairings of form and function as constructions in themselves, and adhere to the rules laid down by other language aspects. Four types of models exist: (1) full-entry model; (2) usage-based model; (3) default inheritance model and (4) complete inheritance model. However, the details of these models are not the focus of this chapter.
Currently there are several recognised construction grammar formalisms and amongst these there are two commonly known ones: Fluid Construction Grammar and Sign-Based Construction Grammar. The former takes the view of language being a working process between cognition and function (worldviews and mental methods of breaking down language structure) while the latter approaches language with a generative notion i.e. classifying whether sentence utterances are accepted as appropriate based on comparisons with descriptions of structures. Fluid Construction Grammar was conceived by Luc Steels (Bergen, 2008) and Sign-Based Construction Grammar by Ivan Sag and Hans Boas (Boas & Sag, 2012). Due to resource constraints we will focus only on Fluid Construction Grammar in this wiki chapter.