27 research outputs found
An Empirical Analysis of Predictive Machine Learning Algorithms on High-Dimensional Microarray Cancer Data
This research evaluates pattern recognition techniques on a subclass of big data where the dimensionality of the input space p is much larger than the number of observations n. Seven gene-expression microarray cancer datasets, where the ratio Īŗ = n/p is less than one, were chosen for evaluation. The statistical and computational challenges inherent with this type of high-dimensional low sample size (HDLSS) data were explored. The capability and performance of a diverse set of machine learning algorithms is presented and compared. The sparsity and collinearity of the data being employed, in conjunction with the complexity of the algorithms studied, demanded rigorous and careful tuning of the hyperparameters and regularization parameters. This necessitated several extensions of cross-validation to be investigated, with the purpose of culminating in the best predictive performance.
For the techniques evaluated in this thesis, regularization or kernelization, and often both, produced lower classiļ¬cation error rates than randomized ensemble for all datasets used in this research. However, no one technique evaluated for classifying HDLSS microarray cancer data emerged as the universally best technique for predicting the generalization error.1
From the empirical analysis performed in this thesis, the following fundamentals emerged as being instrumental in consistently resulting in lower error rates when estimating the generalization error in this HDLSS microarray cancer data:
ā¢ Thoroughly investigate and understand the data
ā¢ Stratify during all sampling due to the uneven classes and extreme sparsity of this data.
ā¢ Perform 3 to 5 replicates of stratiļ¬ed cross-validation, implementing an adaptive K-fold, to determine the optimal tuning parameters.
ā¢ To estimate the generalization error in HDLSS data, replication is paramount. Replicate R=500 or R=1000 times with training and test sets of 2/3 and 1/3, respectively, to get the best generalization error estimate.
ā¢ Whenever possible, obtain an independent validation dataset.
ā¢ Seed the data for a fair and unbiased comparison among techniques.
ā¢ Deļ¬ne a methodology or standard set of process protocols to apply to machine learning research. This would prove very beneļ¬cial in ensuring reproducibility and would enable better comparisons among techniques.
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1A predominant portion of this research was published in the Serdica Journal of Computing (Volume 8, Number 2, 2014) as proceedings from the 2014 Flint International Statistical Conference at Kettering University, Michigan, USA
Handbook of Digital Face Manipulation and Detection
This open access book provides the first comprehensive collection of studies dealing with the hot topic of digital face manipulation such as DeepFakes, Face Morphing, or Reenactment. It combines the research fields of biometrics and media forensics including contributions from academia and industry. Appealing to a broad readership, introductory chapters provide a comprehensive overview of the topic, which address readers wishing to gain a brief overview of the state-of-the-art. Subsequent chapters, which delve deeper into various research challenges, are oriented towards advanced readers. Moreover, the book provides a good starting point for young researchers as well as a reference guide pointing at further literature. Hence, the primary readership is academic institutions and industry currently involved in digital face manipulation and detection. The book could easily be used as a recommended text for courses in image processing, machine learning, media forensics, biometrics, and the general security area
Adopting Automated Bug Assignment in Practice: A Longitudinal Case Study at Ericsson
The continuous inflow of bug reports is a considerable challenge in large
development projects. Inspired by contemporary work on mining software
repositories, we designed a prototype bug assignment solution based on machine
learning in 2011-2016. The prototype evolved into an internal Ericsson product,
TRR, in 2017-2018. TRR's first bug assignment without human intervention
happened in April 2019. Our study evaluates the adoption of TRR within its
industrial context at Ericsson. Moreover, we investigate 1) how TRR performs in
the field, 2) what value TRR provides to Ericsson, and 3) how TRR has
influenced the ways of working. We conduct an industrial case study combining
interviews with TRR stakeholders, minutes from sprint planning meetings, and
bug tracking data. The data analysis includes thematic analysis, descriptive
statistics, and Bayesian causal analysis. TRR is now an incorporated part of
the bug assignment process. Considering the abstraction levels of the
telecommunications stack, high-level modules are more positive while low-level
modules experienced some drawbacks. On average, TRR automatically assigns 30%
of the incoming bug reports with an accuracy of 75%. Auto-routed TRs are
resolved around 21% faster within Ericsson, and TRR has saved highly seasoned
engineers many hours of work. Indirect effects of adopting TRR include process
improvements, process awareness, increased communication, and higher job
satisfaction. TRR has saved time at Ericsson, but the adoption of automated bug
assignment was more intricate compared to similar endeavors reported from other
companies. We primarily attribute the difference to the very large size of the
organization and the complex products. Key facilitators in the successful
adoption include a gradual introduction, product champions, and careful
stakeholder analysis.Comment: Under revie
Handbook of Digital Face Manipulation and Detection
This open access book provides the first comprehensive collection of studies dealing with the hot topic of digital face manipulation such as DeepFakes, Face Morphing, or Reenactment. It combines the research fields of biometrics and media forensics including contributions from academia and industry. Appealing to a broad readership, introductory chapters provide a comprehensive overview of the topic, which address readers wishing to gain a brief overview of the state-of-the-art. Subsequent chapters, which delve deeper into various research challenges, are oriented towards advanced readers. Moreover, the book provides a good starting point for young researchers as well as a reference guide pointing at further literature. Hence, the primary readership is academic institutions and industry currently involved in digital face manipulation and detection. The book could easily be used as a recommended text for courses in image processing, machine learning, media forensics, biometrics, and the general security area
Predicting Academic Performance: A Systematic Literature Review
The ability to predict student performance in a course or program creates opportunities to improve educational outcomes. With effective performance prediction approaches, instructors can allocate resources and instruction more accurately. Research in this area seeks to identify features that can be used to make predictions, to identify algorithms that can improve predictions, and to quantify aspects of student performance. Moreover, research in predicting student performance seeks to determine interrelated features and to identify the underlying reasons why certain features work better than others. This working group report presents a systematic literature review of work in the area of predicting student performance. Our analysis shows a clearly increasing amount of research in this area, as well as an increasing variety of techniques used. At the same time, the review uncovered a number of issues with research quality that drives a need for the community to provide more detailed reporting of methods and results and to increase efforts to validate and replicate work.Peer reviewe
Compilation of thesis abstracts, September 2009
NPS Class of September 2009This quarterās Compilation of Abstracts summarizes cutting-edge, security-related research conducted by NPS students and presented as theses, dissertations, and capstone reports. Each expands knowledge in its field.http://archive.org/details/compilationofsis109452751
PaLM: Scaling Language Modeling with Pathways
Large language models have been shown to achieve remarkable performance
across a variety of natural language tasks using few-shot learning, which
drastically reduces the number of task-specific training examples needed to
adapt the model to a particular application. To further our understanding of
the impact of scale on few-shot learning, we trained a 540-billion parameter,
densely activated, Transformer language model, which we call Pathways Language
Model PaLM. We trained PaLM on 6144 TPU v4 chips using Pathways, a new ML
system which enables highly efficient training across multiple TPU Pods. We
demonstrate continued benefits of scaling by achieving state-of-the-art
few-shot learning results on hundreds of language understanding and generation
benchmarks. On a number of these tasks, PaLM 540B achieves breakthrough
performance, outperforming the finetuned state-of-the-art on a suite of
multi-step reasoning tasks, and outperforming average human performance on the
recently released BIG-bench benchmark. A significant number of BIG-bench tasks
showed discontinuous improvements from model scale, meaning that performance
steeply increased as we scaled to our largest model. PaLM also has strong
capabilities in multilingual tasks and source code generation, which we
demonstrate on a wide array of benchmarks. We additionally provide a
comprehensive analysis on bias and toxicity, and study the extent of training
data memorization with respect to model scale. Finally, we discuss the ethical
considerations related to large language models and discuss potential
mitigation strategies
Entropy in Image Analysis II
Image analysis is a fundamental task for any application where extracting information from images is required. The analysis requires highly sophisticated numerical and analytical methods, particularly for those applications in medicine, security, and other fields where the results of the processing consist of data of vital importance. This fact is evident from all the articles composing the Special Issue "Entropy in Image Analysis II", in which the authors used widely tested methods to verify their results. In the process of reading the present volume, the reader will appreciate the richness of their methods and applications, in particular for medical imaging and image security, and a remarkable cross-fertilization among the proposed research areas