computational modelling Flashcards
why is modelling important (5 reasons)
data never speaks for self,
multiple models to select from
verbal theorising not sub for quantitative analysis
model selection based on quantitative and intellectual/qualitative judgement
psych moving rapidly towards this level of specification
what is a model
abstract framework capturing data’s structure (e.g mean)
simpler version of what’s being explained
Lewandowsky & Farrells 2011 model classification
3 elements
data description = describes relationship b/w variables
process characterisation = explanatory power lies in hypothetical constructs of mind (neutral regarding implementations of processes
process explanation = implement HOW processes occur, not neutral
3 levels of model
computational = what system does & why
algorithmic/representational level = how system does what it does (what rep used, processes to build &manipulate reps)
physical = how systems physically realised
benefits of modelling
model helps understand/explain data
instantiation of quantitative model = all assumptions of theory ID’d and tested
force theorists to be explicit
what is emergence of understanding
models (as comp programs) cannot generate novel ideas - E-Z reader &skipping costs
wrong models and verisimilitude
all models are inherently wrong, but can still be useful
verisimilitude = partial truth value
problems with models
scope and testability - hard to falsify
application of neural networks
txt to speech - NetTalk (Sejnowski and Rosenberg 1988) medical images credit checks stock market national defense handwritten character recognition
what is connectionism (neural networks)
sub symbolic
mimics biology
parallel not serial
emergent properties ( model = grown not built, back propagation learning