678 research outputs found
Relatedness Measures to Aid the Transfer of Building Blocks among Multiple Tasks
Multitask Learning is a learning paradigm that deals with multiple different
tasks in parallel and transfers knowledge among them. XOF, a Learning
Classifier System using tree-based programs to encode building blocks
(meta-features), constructs and collects features with rich discriminative
information for classification tasks in an observed list. This paper seeks to
facilitate the automation of feature transferring in between tasks by utilising
the observed list. We hypothesise that the best discriminative features of a
classification task carry its characteristics. Therefore, the relatedness
between any two tasks can be estimated by comparing their most appropriate
patterns. We propose a multiple-XOF system, called mXOF, that can dynamically
adapt feature transfer among XOFs. This system utilises the observed list to
estimate the task relatedness. This method enables the automation of
transferring features. In terms of knowledge discovery, the resemblance
estimation provides insightful relations among multiple data. We experimented
mXOF on various scenarios, e.g. representative Hierarchical Boolean problems,
classification of distinct classes in the UCI Zoo dataset, and unrelated tasks,
to validate its abilities of automatic knowledge-transfer and estimating task
relatedness. Results show that mXOF can estimate the relatedness reasonably
between multiple tasks to aid the learning performance with the dynamic feature
transferring.Comment: accepted by The Genetic and Evolutionary Computation Conference
(GECCO 2020
Competent Program Evolution, Doctoral Dissertation, December 2006
Heuristic optimization methods are adaptive when they sample problem solutions based on knowledge of the search space gathered from past sampling. Recently, competent evolutionary optimization methods have been developed that adapt via probabilistic modeling of the search space. However, their effectiveness requires the existence of a compact problem decomposition in terms of prespecified solution parameters. How can we use these techniques to effectively and reliably solve program learning problems, given that program spaces will rarely have compact decompositions? One method is to manually build a problem-specific representation that is more tractable than the general space. But can this process be automated? My thesis is that the properties of programs and program spaces can be leveraged as inductive bias to reduce the burden of manual representation-building, leading to competent program evolution. The central contributions of this dissertation are a synthesis of the requirements for competent program evolution, and the design of a procedure, meta-optimizing semantic evolutionary search (MOSES), that meets these requirements. In support of my thesis, experimental results are provided to analyze and verify the effectiveness of MOSES, demonstrating scalability and real-world applicability
Automated Problem Decomposition for the Boolean Domain with Genetic Programming
Researchers have been interested in exploring the regularities and modularity of the problem space in genetic programming (GP) with the aim of decomposing the original problem into several smaller subproblems. The main motivation is to allow GP to deal with more complex problems. Most previous works on modularity in GP emphasise the structure of modules used to encapsulate code and/or promote code reuse, instead of in the decomposition of the original problem. In this paper we propose a problem decomposition strategy that allows the use of a GP search to find solutions for subproblems and combine the individual solutions into the complete solution to the problem
DeepSecure: Scalable Provably-Secure Deep Learning
This paper proposes DeepSecure, a novel framework that enables scalable
execution of the state-of-the-art Deep Learning (DL) models in a
privacy-preserving setting. DeepSecure targets scenarios in which neither of
the involved parties including the cloud servers that hold the DL model
parameters or the delegating clients who own the data is willing to reveal
their information. Our framework is the first to empower accurate and scalable
DL analysis of data generated by distributed clients without sacrificing the
security to maintain efficiency. The secure DL computation in DeepSecure is
performed using Yao's Garbled Circuit (GC) protocol. We devise GC-optimized
realization of various components used in DL. Our optimized implementation
achieves more than 58-fold higher throughput per sample compared with the
best-known prior solution. In addition to our optimized GC realization, we
introduce a set of novel low-overhead pre-processing techniques which further
reduce the GC overall runtime in the context of deep learning. Extensive
evaluations of various DL applications demonstrate up to two
orders-of-magnitude additional runtime improvement achieved as a result of our
pre-processing methodology. This paper also provides mechanisms to securely
delegate GC computations to a third party in constrained embedded settings
Scalable genetic programming by gene-pool optimal mixing and input-space entropy-based building-block learning
The Gene-pool Optimal Mixing Evolutionary Algorithm (GOMEA) is a recently introduced model-based EA that has been shown to be capable of outperforming state-of-the-art alternative EAs in terms of scalability when solving discrete optimization problems. One of the key aspects of GOMEA's success is a variation operator that is designed to extensively exploit linkage models by effectively combining partial solutions. Here, we bring the strengths of GOMEA to Genetic Programming (GP), introducing GP-GOMEA. Under the hypothesis of having little problem-specific knowledge, and in an effort to design easy-to-use EAs, GP-GOMEA requires no parameter specification. On a set of well-known benchmark problems we find that GP-GOMEA outperforms standard GP while being on par with more recently introduced, state-of-the-art EAs. We furthermore introduce Input-space Entropy-based Building-block Learning (IEBL), a novel approach to identifying and encapsulating relevant building blocks (subroutines) into new terminals and functions. On problems with an inherent degree of modularity, IEBL can contribute to compact solution representations, providing a large potential for knock-on effects in performance. On the difficult, but highly modular Even Parity problem, GP-GOMEA+IEBL obtains excellent scalability, solving the 14-bit instance in less than 1 hour
Asynchronous Evolution of Deep Neural Network Architectures
Many evolutionary algorithms (EAs) take advantage of parallel evaluation of
candidates. However, if evaluation times vary significantly, many worker nodes
(i.e.,\ compute clients) are idle much of the time, waiting for the next
generation to be created. Evolutionary neural architecture search (ENAS), a
class of EAs that optimizes the architecture and hyperparameters of deep neural
networks, is particularly vulnerable to this issue. This paper proposes a
generic asynchronous evaluation strategy (AES) that is then adapted to work
with ENAS. AES increases throughput by maintaining a queue of upto
individuals ready to be sent to the workers for evaluation and proceeding to
the next generation as soon as individuals have been evaluated by the
workers. A suitable value for is determined experimentally, balancing
diversity and efficiency. To showcase the generality and power of AES, it was
first evaluated in 11-bit multiplexer design (a single-population verifiable
discovery task) and then scaled up to ENAS for image captioning (a
multi-population open-ended-optimization task). In both problems, a multifold
performance improvement was observed, suggesting that AES is a promising method
for parallelizing the evolution of complex systems with long and variable
evaluation times, such as those in ENAS
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