PurposeSome degree programs in colleges and universities utilize entrance exams to ensure that st... more PurposeSome degree programs in colleges and universities utilize entrance exams to ensure that students pursuing a given degree have mastered foundational concepts needed for that program. However, often these exams become a barrier to student success. The purpose of this study is to discuss the impact of policies governing an undergraduate Computer Science (CS) entry/qualifying exam at a large public university in the United States on overall student success in the program. This case study focuses on whether reforming program policies impacts students' time-to-degree, graduation and mastery in CS core skills.Design/methodology/approachThis case study describes how the CS student success was improved by updating program policies based on institutional data and the input of course instructors. The policy changes include introducing a maximum limit to attempt the exam, changing the exam requirements as well as the structure of the exam itself.FindingsThe pass rates of students tak...
This work explores simulations of polarized discussions from a general and theoretical premise. S... more This work explores simulations of polarized discussions from a general and theoretical premise. Specifically the question of whether a plausible avenue exists for a subgroup in an online social network to find a disagreement beneficial and what that benefit could be. A methodological framework is proposed which represents key factors that drives social media engagement including the iterative accumulation of influence and the dynamics for the asymmetric treatment of messages during a disagreement. It is shown that prior to a polarization event a trend towards a more uniform distribution of relative influence is achieved which is then reversed by the polarization event. The reasons for this reversal are discussed and how it has a plausible analogue in real world systems. A pair of inoculation strategies are proposed which aim at returning the trend towards uniform influence across users while refraining from violating user privacy (by remaining topic agnostic) and from user removal operations.
Social networking platforms connect people from all around the world. Because of their user-frien... more Social networking platforms connect people from all around the world. Because of their user-friendliness and easy accessibility, their traffic is increasing drastically. Such active participation has caught the attention of many research groups that are focusing on understanding human behavior to study the dynamics of these social networks. Oftentimes, perceiving these networks is hard, mainly due to either the large size of the data involved or the ineffective use of visualization strategies. This work introduces VizTract to ease the visual perception of complex social networks. VizTract is a two-level graph abstraction visualization tool that is designed to visualize both hierarchical and adjacency information in a tree structure. We use the Facebook dataset from the Social Network Analysis Project from Stanford University. On this data, social groups are referred as circles, social network users as nodes, and interactions as edges between the nodes. Our approach is to present a v...
Polarization in online social networks has gathered a significant amount of attention in the rese... more Polarization in online social networks has gathered a significant amount of attention in the research community and in the public sphere due to stark disagreements with millions of participants in topics surrounding politics, climate, the economy and other areas where an agreement is required. There are multiple approaches to investigating the scenarios in which polarization occurs and given that polarization is not a new phenomenon but that its virality may be supported by the low cost and latency messaging offered by online social media platforms; an investigation into the intrinsic dynamics of online opinion evolution is presented for complete networks. Extending a model which utilizes the Binary Voter Model (BVM) to examine the effect of the degree of freedom for selecting contacts based upon homophily, simulations show that different opinions are reinforced for a period of time when users have a greater range of choice for association. The facility of discussion threads and gro...
Proceedings of the Genetic and Evolutionary Computation Conference, Apr 9, 2002
We have developed a genetic algorithm (GA) with a new representation method which we call the pro... more We have developed a genetic algorithm (GA) with a new representation method which we call the proportional GA (PGA). The PGA representation focuses on the idea that it is the content rather than the order of the encoded information that matters. As a result, the PGA representation is based on multisets rather than permutations. We extend the idea of location independent representations to a generally usable encoding for integer and oating point numbers. Specifically, the PGA assigns one or more unique characters to each ...
A fast and elitist multiobjective genetic algorithm - Deb, Pratap, et al. ... Ant algorithms for ... more A fast and elitist multiobjective genetic algorithm - Deb, Pratap, et al. ... Ant algorithms for discrete optimization - Dorigo, Caro, et al. ... L.: Optimal Design of Water Distribution System by Multiobjective Evolutionary Methods - Formiga, Chaudhry, et al. ... Structured Messy Genetic Algorithm Approach for the Optimal Improvement of the Water Distribution Systems. CAP5512: Evolutionary Computation at UCF, Student Papers, Spring 2007 - Halhal, Walters, et al.
Page 1. CAP5512 : Homework 2 The Evolution of Cooperation http://ivan.research.ucf.edu/classes/ C... more Page 1. CAP5512 : Homework 2 The Evolution of Cooperation http://ivan.research.ucf.edu/classes/ CAP5512 Spring2007/ Due: February 13, 2007 Ivan I. Garibay School of Electrical Engineering and Computer Science University of Central Florida 1 Objective ...
We analyze two Boolean function networks with different degrees of neutrality. The results show t... more We analyze two Boolean function networks with different degrees of neutrality. The results show that the one with explicit neutrality is a small-world network where each pair of possible solutions has a short distance and most of the possible solutions are highly clustered. These network structural properties owe their existence to the "short cuts" introduced by redundant genes in the genotypes. We explain some important small-world network structures, such as clusters, hubs and power law link distribution. These properties have potential to be useful in designing efficient evolutionary algorithms to navigate search in the network.
The process of documenting designs is tedious and often error-prone. We discuss a system that au-... more The process of documenting designs is tedious and often error-prone. We discuss a system that au- tomatically generates documentation for the single step transition behavior of Statecharts with particu- lar focus on the correctness of the result in the sense that the document will present all and only the facts corresponding to the design being documented. Our approach is to translate the Statechart into a propositional formula, then translate this formula into a natural language report. In the later transla- tion pragmatic effects arise due to the way the in- formation is presented. Whereas such effects can be difficult to quantify, we account for them within an abstract framework by applying a series of transfor- mations on the structure on the report while pre- serving soundness and completeness of the logical content. The result is an automatically generated hypertext report that is both logically correct and, to a relatively high degree of confidence, free of mis- leading impli...
Abstract A key property for predicting the effectiveness of stochastic search techniques, includi... more Abstract A key property for predicting the effectiveness of stochastic search techniques, including evolutionary algorithms, is the existence of a positive correlation between the form and the quality of candidate solutions. In this paper we show that when the ordering of genomic symbols in a genetic algorithm is completely independent of the fitness function and therefore free to evolve along with the candidate solutions it encodes, the resulting genomes self-organize into self-similar structures that favor this key stochastic search ...
Page 1. The modular genetic algorithm: motivation and first results on repetitive modularity Ozle... more Page 1. The modular genetic algorithm: motivation and first results on repetitive modularity Ozlem O. Garibay, Ivan I. Garibay and Annie S. Wu {ozlem,igaribay,aswu}@ cs.ucf.edu University of Central Florida school of Electrical ...
PurposeSome degree programs in colleges and universities utilize entrance exams to ensure that st... more PurposeSome degree programs in colleges and universities utilize entrance exams to ensure that students pursuing a given degree have mastered foundational concepts needed for that program. However, often these exams become a barrier to student success. The purpose of this study is to discuss the impact of policies governing an undergraduate Computer Science (CS) entry/qualifying exam at a large public university in the United States on overall student success in the program. This case study focuses on whether reforming program policies impacts students' time-to-degree, graduation and mastery in CS core skills.Design/methodology/approachThis case study describes how the CS student success was improved by updating program policies based on institutional data and the input of course instructors. The policy changes include introducing a maximum limit to attempt the exam, changing the exam requirements as well as the structure of the exam itself.FindingsThe pass rates of students tak...
This work explores simulations of polarized discussions from a general and theoretical premise. S... more This work explores simulations of polarized discussions from a general and theoretical premise. Specifically the question of whether a plausible avenue exists for a subgroup in an online social network to find a disagreement beneficial and what that benefit could be. A methodological framework is proposed which represents key factors that drives social media engagement including the iterative accumulation of influence and the dynamics for the asymmetric treatment of messages during a disagreement. It is shown that prior to a polarization event a trend towards a more uniform distribution of relative influence is achieved which is then reversed by the polarization event. The reasons for this reversal are discussed and how it has a plausible analogue in real world systems. A pair of inoculation strategies are proposed which aim at returning the trend towards uniform influence across users while refraining from violating user privacy (by remaining topic agnostic) and from user removal operations.
Social networking platforms connect people from all around the world. Because of their user-frien... more Social networking platforms connect people from all around the world. Because of their user-friendliness and easy accessibility, their traffic is increasing drastically. Such active participation has caught the attention of many research groups that are focusing on understanding human behavior to study the dynamics of these social networks. Oftentimes, perceiving these networks is hard, mainly due to either the large size of the data involved or the ineffective use of visualization strategies. This work introduces VizTract to ease the visual perception of complex social networks. VizTract is a two-level graph abstraction visualization tool that is designed to visualize both hierarchical and adjacency information in a tree structure. We use the Facebook dataset from the Social Network Analysis Project from Stanford University. On this data, social groups are referred as circles, social network users as nodes, and interactions as edges between the nodes. Our approach is to present a v...
Polarization in online social networks has gathered a significant amount of attention in the rese... more Polarization in online social networks has gathered a significant amount of attention in the research community and in the public sphere due to stark disagreements with millions of participants in topics surrounding politics, climate, the economy and other areas where an agreement is required. There are multiple approaches to investigating the scenarios in which polarization occurs and given that polarization is not a new phenomenon but that its virality may be supported by the low cost and latency messaging offered by online social media platforms; an investigation into the intrinsic dynamics of online opinion evolution is presented for complete networks. Extending a model which utilizes the Binary Voter Model (BVM) to examine the effect of the degree of freedom for selecting contacts based upon homophily, simulations show that different opinions are reinforced for a period of time when users have a greater range of choice for association. The facility of discussion threads and gro...
Proceedings of the Genetic and Evolutionary Computation Conference, Apr 9, 2002
We have developed a genetic algorithm (GA) with a new representation method which we call the pro... more We have developed a genetic algorithm (GA) with a new representation method which we call the proportional GA (PGA). The PGA representation focuses on the idea that it is the content rather than the order of the encoded information that matters. As a result, the PGA representation is based on multisets rather than permutations. We extend the idea of location independent representations to a generally usable encoding for integer and oating point numbers. Specifically, the PGA assigns one or more unique characters to each ...
A fast and elitist multiobjective genetic algorithm - Deb, Pratap, et al. ... Ant algorithms for ... more A fast and elitist multiobjective genetic algorithm - Deb, Pratap, et al. ... Ant algorithms for discrete optimization - Dorigo, Caro, et al. ... L.: Optimal Design of Water Distribution System by Multiobjective Evolutionary Methods - Formiga, Chaudhry, et al. ... Structured Messy Genetic Algorithm Approach for the Optimal Improvement of the Water Distribution Systems. CAP5512: Evolutionary Computation at UCF, Student Papers, Spring 2007 - Halhal, Walters, et al.
Page 1. CAP5512 : Homework 2 The Evolution of Cooperation http://ivan.research.ucf.edu/classes/ C... more Page 1. CAP5512 : Homework 2 The Evolution of Cooperation http://ivan.research.ucf.edu/classes/ CAP5512 Spring2007/ Due: February 13, 2007 Ivan I. Garibay School of Electrical Engineering and Computer Science University of Central Florida 1 Objective ...
We analyze two Boolean function networks with different degrees of neutrality. The results show t... more We analyze two Boolean function networks with different degrees of neutrality. The results show that the one with explicit neutrality is a small-world network where each pair of possible solutions has a short distance and most of the possible solutions are highly clustered. These network structural properties owe their existence to the "short cuts" introduced by redundant genes in the genotypes. We explain some important small-world network structures, such as clusters, hubs and power law link distribution. These properties have potential to be useful in designing efficient evolutionary algorithms to navigate search in the network.
The process of documenting designs is tedious and often error-prone. We discuss a system that au-... more The process of documenting designs is tedious and often error-prone. We discuss a system that au- tomatically generates documentation for the single step transition behavior of Statecharts with particu- lar focus on the correctness of the result in the sense that the document will present all and only the facts corresponding to the design being documented. Our approach is to translate the Statechart into a propositional formula, then translate this formula into a natural language report. In the later transla- tion pragmatic effects arise due to the way the in- formation is presented. Whereas such effects can be difficult to quantify, we account for them within an abstract framework by applying a series of transfor- mations on the structure on the report while pre- serving soundness and completeness of the logical content. The result is an automatically generated hypertext report that is both logically correct and, to a relatively high degree of confidence, free of mis- leading impli...
Abstract A key property for predicting the effectiveness of stochastic search techniques, includi... more Abstract A key property for predicting the effectiveness of stochastic search techniques, including evolutionary algorithms, is the existence of a positive correlation between the form and the quality of candidate solutions. In this paper we show that when the ordering of genomic symbols in a genetic algorithm is completely independent of the fitness function and therefore free to evolve along with the candidate solutions it encodes, the resulting genomes self-organize into self-similar structures that favor this key stochastic search ...
Page 1. The modular genetic algorithm: motivation and first results on repetitive modularity Ozle... more Page 1. The modular genetic algorithm: motivation and first results on repetitive modularity Ozlem O. Garibay, Ivan I. Garibay and Annie S. Wu {ozlem,igaribay,aswu}@ cs.ucf.edu University of Central Florida school of Electrical ...
We introduce an approach to modeling economies that focuses on the interconnectedness of economic... more We introduce an approach to modeling economies that focuses on the interconnectedness of economic agents. This ecosystembased approach allows us to enhance our understanding of economic growth by accounting for how the interactions of one agent directly impacts the local neighborhood and indirectly impacts the global system. The specific approach that we take to modeling economic ecosystems emphasizes technology and innovation in an attempt to account for gaps in the current literature on economic growth.
Aedes Aegypti is the vector of several deadly diseases, including Zika. Effective and sustainable... more Aedes Aegypti is the vector of several deadly diseases, including Zika. Effective and sustainable vector control measures must be deployed to keep A. aegypti numbers under control. The distribution of A. Aegypti is subject to spatial and climatic constraints. Using agent-based modeling, we model the population dynamics of A. aegypti subjected to the spatial and climatic constraints of a neighborhood in the Key West. Satellite imagery was used to identify vegetation, houses(CO2 zones) both critical to the mosquito lifecycle. The model replicates the annual fluctuation of adult population sampled through field studies and approximates the population between 1 per 12m 2 during summer and 1 per 59 m 2 during winter. We then simulate two biological vector control strategies: 1) Release of Insects carrying a Dominant Lethal gene (RIDL) and 2) Wolbachia infection. Our results support the sustainability of Wolbachia infection within the population from the year of treatment onto the next. For the assessment of these two strategies, our approach provides a realistic simulation environment consisting of male and female Aedes aegypti, breeding spots, vegetation and CO2 sources.
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