10 research outputs found
Reachability Analysis for Lexicase Selection via Community Assembly Graphs
Fitness landscapes have historically been a powerful tool for analyzing the
search space explored by evolutionary algorithms. In particular, they
facilitate understanding how easily reachable an optimal solution is from a
given starting point. However, simple fitness landscapes are inappropriate for
analyzing the search space seen by selection schemes like lexicase selection in
which the outcome of selection depends heavily on the current contents of the
population (i.e. selection schemes with complex ecological dynamics). Here, we
propose borrowing a tool from ecology to solve this problem: community assembly
graphs. We demonstrate a simple proof-of-concept for this approach on an NK
Landscape where we have perfect information. We then demonstrate that this
approach can be successfully applied to a complex genetic programming problem.
While further research is necessary to understand how to best use this tool, we
believe it will be a valuable addition to our toolkit and facilitate analyses
that were previously impossible
Matchmaker, Matchmaker, Make Me a Match: Geometric, Variational, and Evolutionary Implications of Criteria for Tag Affinity
Genetic programming and artificial life systems commonly employ tag-matching
schemes to determine interactions between model components. However, the
implications of criteria used to determine affinity between tags with respect
to constraints on emergent connectivity, canalization of changes to
connectivity under mutation, and evolutionary dynamics have not been
considered. We highlight differences between tag-matching criteria with respect
to geometric constraint and variation generated under mutation. We find that
tag-matching criteria can influence the rate of adaptive evolution and the
quality of evolved solutions. Better understanding of the geometric,
variational, and evolutionary properties of tag-matching criteria will
facilitate more effective incorporation of tag matching into genetic
programming and artificial life systems. By showing that tag-matching criteria
influence connectivity patterns and evolutionary dynamics, our findings also
raise fundamental questions about the properties of tag-matching systems in
nature
Born to learn: The inspiration, progress, and future of evolved plastic artificial neural networks
Biological plastic neural networks are systems of extraordinary computational
capabilities shaped by evolution, development, and lifetime learning. The
interplay of these elements leads to the emergence of adaptive behavior and
intelligence. Inspired by such intricate natural phenomena, Evolved Plastic
Artificial Neural Networks (EPANNs) use simulated evolution in-silico to breed
plastic neural networks with a large variety of dynamics, architectures, and
plasticity rules: these artificial systems are composed of inputs, outputs, and
plastic components that change in response to experiences in an environment.
These systems may autonomously discover novel adaptive algorithms, and lead to
hypotheses on the emergence of biological adaptation. EPANNs have seen
considerable progress over the last two decades. Current scientific and
technological advances in artificial neural networks are now setting the
conditions for radically new approaches and results. In particular, the
limitations of hand-designed networks could be overcome by more flexible and
innovative solutions. This paper brings together a variety of inspiring ideas
that define the field of EPANNs. The main methods and results are reviewed.
Finally, new opportunities and developments are presented
Collection of Accountancy Case Studies
The following collection of case studies examines various personal and professional topics in accounting. These topics range from personal research and reflection on important topics within the profession to a comprehensive case competition focusing on The Coca-Cola Company. Throughout the collection, theoretical accounting frameworks and solutions are applied to real world scenarios. In addition to theoretical frameworks, financial statements and relevant outside sources are used with applicable
A suite of diagnostic metrics for characterizing selection schemes
Evolutionary algorithms are effective general-purpose techniques for solving
optimization problems. Understanding how each component of an evolutionary
algorithm influences its problem-solving success improves our ability to target
particular problem domains. Our work focuses on evaluating selection schemes,
which choose individuals to contribute genetic material to the next generation.
We introduce four diagnostic search spaces for testing the strengths and
weaknesses of selection schemes: the exploitation rate diagnostic, ordered
exploitation rate diagnostic, contradictory objectives diagnostic, and the
multi-path exploration diagnostic. Each diagnostic is handcrafted to isolate
and measure the relative exploitation and exploration characteristics of
selection schemes. In this study, we use our diagnostics to evaluate six
population selection methods: truncation selection, tournament selection,
fitness sharing, lexicase selection, nondominated sorting, and novelty search.
Expectedly, tournament and truncation selection excelled in gradient
exploitation but poorly explored search spaces, and novelty search excelled at
exploration but failed to exploit fitness gradients. Fitness sharing performed
poorly across all diagnostics, suggesting poor overall exploitation and
exploration abilities. Nondominated sorting was best for maintaining
populations comprised of individuals with different trade-offs of multiple
objectives, but struggled to effectively exploit fitness gradients. Lexicase
selection balanced search space exploration with exploitation, generally
performing well across diagnostics. Our work demonstrates the value of
diagnostic search spaces for building a deeper understanding of selection
schemes, which can then be used to improve or develop new selection methods
Data Standards for Artificial Life Software
International audienc
MergeBathy (2015)
Developed in C++, MergeBathy (2015) is cross-platform and multi-threaded software suite for constructing digital bathymetric models. It provides the user with a set of modeling tools to construct custom bathymetric surfaces, including splines-in-tension routines for interpolation output or as an intermediate resampling step when merging multiple bathymetry data sets. Notable to MergeBathy is its user-friendly and flexible processing options made possible from its integrated bathymetric process framework. Keywords: MergeBathy, Bathymetry, Digital elevation models, Software, Tool, Modelin