README for SimpleCrowdingModelArchive
This is the source code and supporting data files for the "Simple Crowding Model" used to generate the fits 
in Kieras(2020) technical report:

Kieras, D. (2020). Visual Search Explained with a Computational Cognitive Architecture: Early
Visual Processes, Eye Movements, and Task Strategies. 
Technical Report TR-20/ONR-EPIC-21, 
University of Michigan Electrical Engineering and Computer Science Department.
August 20, 2020. DTIC AD1114079 DOI: 10.13140/RG.2.2.23716.91520.

The code was written in Standard C++ 17. It should need at most only minor updating to run in newer
versions of C++. The .xcodeproj is the project file for running in Apple's Xcode environment, but
this can be replaced by a simple makefile or even simply compile *.cpp to produce the executable.

SourceCode contains the source code files. The top level main() module is CrowdingSim.cpp. 

The major submodules are Program_constants, Display_creator, Search_object, Visual_model, Strategy, 
PrdObsStatistics, and Trial_statistics. 

The model is configured for a particular condition, strategy, and visual parameters by editing the contents
of Program_constants.cpp.

The program reads the observed data values from one of the files in RunTimeInputFiles, and uses these
to compute goodness of fit statistics and output a table that can be copy-pasted into Excel to produce
graphs of the predicted and observed results.

The model code here has copies of components from the EPIC Architecture Simulation System.
This was used in order to maximize code sharing between this specialized 
but efficient model-fitting software and the general production-system-based EPIC architecture. 
This is the source of the many .h,.cpp file pairs such as Geometry, Random_utilities, etc.

Fits_for_report contains Excel files used to produce the graphs in the report.

The observed input data files are in the directory RunTimeInputFiles. These data were 
derived from the data files made available by Wolfe at 
Visual Attention Lab (n.d.). Data Sets and look up Stimulus Sets: What can 8000 trials tell you
about visual search? Retrieved April 23, 2018 from http://search.bwh.harvard.edu/new/data_set_files.html.

