Dietrich College Honors Theses

Incorporating Flexibility into the Normalized Cut Image Segmentation Algorithm

Yi Xiang Chong — Mon, 17 Dec 2012 09:22:49 PST

Image segmentation is the process of dividing a digital image into individual segments which share similar visual characteristics. The Normalized Cut (NCut) algorithm is one of the commonly used graph-based approaches in image segmentation. The NCut algorithm aims to extract big picture segments or global features of an image, a process which closely resembles how a human would approach image segmentation [1]. However, the algorithm is heavily dependent on a constant tuning parameter that is subject to arbitrary assignment prior to running the algorithm. This tuning parameter is independent of the image and indirectly specifies the level of details in the image one requires from the segmentation. Given this shortcoming, we propose a more flexible approach that introduces a local tuning parameter for each pixel over a small neighborhood in the image. We believe that the tuning parameter should represent the local variation of the features in the image in order to correctly tune the necessary components in the segmentation process. In particular, we look at improving the segmentations by introducing multiple "local-variation" tuning parameters that are adjusted to specific regions of the image. We do this through a semi-supervised method, where the regions are defined using the segmentations of the original NCut algorithm. Through our methodology, we incorporate additional local variation into tuning the algorithm without sacrificing the global features extracted by the original NCut algorithm. Results show that our methodology manages to improve the original NCut segmentations for some sample images.

Religion, discrimination and assimilation: a comparison of contemporary France and the United States

Huma Ali — Mon, 29 Oct 2012 12:18:53 PDT

France and the United States are both secular Western countries that are founded upon similar Enlightenment ideals. By virtue of these similarities, one might expect these countries to have similar relationships between church and state. In actuality, however, the secularism that France and the United States both value is a very loosely defined concept whose interpretation and application can widely vary. Specifically, these countries sharply differ in how they interpret the principle of segregation of church and state, how they organize religious diversity, and how the state treats it. Each of these countries’ relationships with religion profoundly affects the assimilation of a minority group. France interprets its secularism as a stark relegation of religion to the private sphere, and in passing the recent headscarves ban, has introduced barriers for the nation’s Muslim subpopulation. Meanwhile, the United States’ culture of religiosity allows for private matters, such as sexual orientation, to become a public concern, as is the case in the ongoing debate surrounding same-sex marriage. While both countries’ debates discuss religion’s role with respect to the preservation of national integrity, France and the United States should instead recognize that they are actually depriving these minorities of a sense of national belonging and work to encourage further civic assimilation.

The influence of familiarity on the ability to form associations: A connectionist account

Alexander Keinath — Mon, 29 Oct 2012 12:18:51 PDT

Examination of numerous past results, such as word frequency effects, suggests that there might be an influence of stimulus familiarity on the ability to form associations with that stimulus. Specifically, that familiarity facilitates association formation. However, to date there has been no direct experimental evidence of this effect. To demonstrate familiarity facilitation, as well as to examine other variables thought to modulate the effect of familiarity facilitation, two experiments were conducted. Evidence in favor of familiarity facilitation, modulated by stimulus complexity and amount/quality of prior exposure, was found. Additionally, it is noted that this behavior appears to resemble that of an autoencoder network, suggesting that autoencoder-like processing might be in part the source of these effects. Application of these results is also briefly discussed.

Improving Task Performance in an Affect-mediated Computing System

Vivek Pai — Mon, 29 Oct 2012 11:01:14 PDT

Computing systems have traditionally relied on purely quantitative means of assessing users. Software may record facts about users such as their click behaviors, their accuracies, and their rates of recurrence, and may then use this acquired data to make predictions about their behaviors and preferences. However, users’ inputs into a machine, sequences of key presses and mouse movements, do not capture all of their desires and needs. The machine may never know that a particular user enjoys the glow of a button and its placement among others elements of an interface. Furthermore, it cannot perceive a user’s discomfort during accomplishing a task; it may simply translate the user’s high accuracy in hitting various steps of a process into a mastery of the task. The machine, which might be intelligent, may not sense the user’s uncertainty of his or her actions, expressed by widened eyes, a stutter in voice, and a hand clasped behind the neck.

In this project, we explore how an affect-mediated system, a computing system that adapts its actions and behavior to the emotional state of its users, can improve their abilities to complete tasks and meet their goals. In particular, we apply facial expression recognition, one method for estimating a human’s emotional state, to a children’s game, giving it the ability to adjust its difficulty based on its player’s perceived unease. Through experimentation with this game, we determine whether affect-mediation helps users achieve their goal of winning the game, and whether in general affect-mediated systems can aid in user task completion.

Our study consisted of two conditions: affect (the game would adjust its difficulty based on the player’s emotion) and control. Participants in the affect condition tended to have a higher catch/total ratio (the number of items caught by the participant divided by the total number of items spawned in the game). They also had less struggles (a catch followed by one or several misses) and these struggles were more spread out than in the control condition, suggesting a higher level of engagement.

Hand Grenade on a Hot Day

Kyle Rood — Mon, 29 Oct 2012 11:01:11 PDT

I
Graffiti
Crown of Thorns
Evening on the Diamond
Form of My Father
Blood on the Chopping Block
Going Downstream

II
Hand Grenade on a Hot Day
Up in Smoke
The Smell of Shit
Do You Think I'm Easy?
A Moment of Recognition
If Only
Die Trying

III
The Barber
Childhood Forté
The Physics of Violence
Eyes Wide Open
What's It Worth?
Someone Else's House
It's Not Alright
Addicted to Your Memory
Misery
The Bones Beneath the Skin

In Our Father’s House -- A Novel

Caroline Roper — Mon, 29 Oct 2012 11:01:07 PDT

Voting for Vichy: Careers of French Legislators, 1940‐1958

Amanda Russell — Mon, 29 Oct 2012 11:01:05 PDT

On July 10, 1940, in the humiliating aftermath of a triumphant German invasion, 570 members of the French National Assembly voted extraordinary powers to the Prime Minister, Philippe Pétain (see Table 1). 1 Although Pétain had been in office less than a month, he enjoyed such universal admiration and esteem that his rapid ascension to power gave hope to the shell‐shocked citizens of the Third Republic.2 For a generation of men who had fought in the trenches of World War I, no man could have been more suitable or worthy of command than Pétain, hero of the Battle of Verdun and one of only two living Marshals of France. Already eighty‐four years old in 1940, Pétain’s life of dutiful service had marked him with a reputation of being just, fair, and, above all, devoted to the French nation.4 Who could be more trusted to use virtually unlimited power for reconstruction and renewal than Pétain, a man known even to his opponents as a veritable “[incarnation] […] [of] traditional French virtues”?

Gumbo: an application to support impromptu collaborative workspaces on campus

Molly Samuels — Mon, 29 Oct 2012 11:01:02 PDT

Gumbo is a web application that supports the creation of impromptu collaborative workspaces on the Carnegie Mellon University campus. The application prompts students to share information about what they are working on and where on campus they are working. Students may join others in a workspace for the purpose of maintaining focus and productivity, collecting feedback on a creative project, or collaborating on group work. This project describes the creation of Gumbo, from early user research through the development of a final prototype.

The Rising Cost of Diabetes Care: Annual Variations in Expenditures, Decomposed by Price and Utilization

Ashish P. Thakrar — Mon, 29 Oct 2012 11:00:56 PDT

This project aims to analyze health care spending for patients with diabetes from 2006 to 2010. We begin by reviewing descriptive data on rising health care costs and the rising prevalence of diabetes nationwide, with a focus on the state of Florida. In our analysis, we use inpatient hospital data from Florida to construct an index that measures changes in health expenditures for diabetics. Based on these calculations, inpatient hospital spending on diabetes increased 23% for those insured by Medicaid, 25% for those insured by Medicare, and 10% for those with private insurance. We decompose these expenditure indexes into price and quantity components to understand whether increased spending is driven by higher prices or increased utilization. These indices are further broken down into age and sex cohorts. Overall we find significant variation in price and quantity changes, with the highest price increases for Medicaid recipients and greatest utilization increases for those with private insurance. Shifts in expenditures for females were generally driven by increased utilization, while shifts in expenditures for men were driven by price increases.

Maximizing Renewable Electricity in Israel: Energy Security, Environmental Impact, and Economic Development

Rebecca A. Yasner — Mon, 29 Oct 2012 11:00:50 PDT

The search for energy security and growing concerns over global environmental degradation, juxtaposed against the promise of economic development, have led to increased worldwide attention to the implementation of renewable electricity technologies. For the State of Israel, located amidst a hostile neighborhood of oilsupplying countries, the need for energy security is paramount. In addition, Israel’s global obligation to reduce negative environmental impacts has become a major focus of public policy. Moreover, favorable forecasts of economic growth in the Clean Technology industry in Israel are now the driving force behind sustainable innovation. It is in Israel’s best interests to make the implementation of renewable electricity in Israel a high priority through public policy initiatives as well as through industry development. The February 2010 Plan for the Integration of Renewable Energy Sources into the Israeli Electricity Sector (PIRES) by Israel’s Ministry of Energy and Water Resources, while well intentioned, falls short of putting Israel on track for large-scale, integrated deployment of renewable electricity technologies. The centerpiece of this study is the author’s modifications to this document, Yasner-PIRES (Y-PIRES), which will not only lead Israel to much needed electricity security, but will also help to reduce harmful environmental pollution and will provide extensive economic development through a more comprehensive implementation of renewable power into Israel’s electricity mix.

Open-Ended Play With Magnetic Unit Blocks: The Educational and Collaborative Impact of Modular Mighty Magz on 4-6 Year-Old Children

Benjamin Scott Coulson Howe — Fri, 26 Oct 2012 13:37:29 PDT

The goal of this study was to investigate whether young children’s collaborative play and learning about magnetism could be enhanced by open-ended play with an innovative type of magnetic unit blocks that teachers could use in conjunction with an explicit lesson about magnetism. This research was completed as part of a dual thesis: the BXA Capstone Project and the H&SS Honors Thesis. The BXA Capstone Project was dedicated to the design and construction of the toy: Modular Mighty Magz. The H&SS Honors Thesis was dedicated to the experimental evaluation of the educational and collaborative impact of Modular Mighty Magz. The four-year-olds and kindergarten children at the Carnegie Mellon Children’s School participated in four different assessments. Children were given a three part pre- and post-test interview that asked questions about magnets and magnetic fields, magnetic poles, and magnetic versus non-magnetic objects. Between the pre- and post-test interviews, the children’s teachers did a group lesson about magnetism during circle time and then gave the children time in groups of four to play with either Modular Mighty Magz or a common magnet toy, Mega Magz, in a separate room for 15 minutes. The play time was used to determine the collaborative impact of Modular Mighty Magz versus Mega Magz. A 2 (age [four-year-olds/kindergarten]) x 2 (toy [Modular Mighty Magz/Mega Magz]) mixed design ANOVA was conducted for all four of the dependent measures. Overall the results showed that every child improved, with kindergartners performing better than the four-year-olds, between the pre- and post-test interviews on the magnet and magnetic field questions and magnetic pole questions. This demonstrated the creation of an effective teacher lesson. There was a three-way interaction between age, toy used, and the magnetic versus non-magnetic object questions. It was determined that the four-year-olds did not improve on this test or have any benefit in which toy they used. However, the children who were given Modular Mighty Magz and were in kindergarten had a significant improvement in responses to these questions whereas those who got the Mega Magz did not improve on their scores. Children in both age groups spent significantly more time collaborating with the Modular Mighty Magz than with the Mega Magz. Thus, the teacher lesson effectively taught the children concepts of magnetism. Even with only a fifteen minute play session, the materials I designed, Modular Mighty Magz, were more effective than an existing toy in improving concepts for the kindergartners regarding magnetic versus non-magnetic objects and in promoting collaboration for all ages.

An Analysis of the Three Signal Sir Phillip Sidney Game

Patrick Kane — Fri, 26 Oct 2012 13:37:26 PDT

An overly simplistic view of evolution would say that it consists only of competition between individuals to survive. However, in actuality ecosystems are often characterized by partial common interest, that is at least some of the time it is in individuals’ best interest to cooperate. Most obviously this occurs in the case of close kin, who share a large portion of common genes and thus will be at least partially successful at passing on their genes to the next generation should their actions ensure the survival of their kin at their own expense. Less obvious but still worth mentioning is that partial common interest can arise between species, even ones with an antagonistic relationship. Consider a predator species A and its prey species B. Members of A can only catch the weaker members of B, if they attempt to catch a strong member of B both will expend resources in the chase and A will get no dinner from it. This is an outcome that neither the strong member of B nor the member of A would like, and so it is in their best interest to develop some way in which the members of B can indicate if they are strong. However, weak members of B who will be eaten if they are chased, have it in their best interest to mimic the “strong signal.” Thus there is only partial common interest, for some individuals it is best to cooperate with the enemy and for others it is best to deceive them.

Understanding and Supporting the Role of Distinct Caregivers of Children with Special Needs, Behavior Problems and/or placed on the Autism Spectrum, enrolled in an Alternative School Placement

Shruti Kataria — Fri, 26 Oct 2012 13:37:23 PDT

This thesis report is a summary of a two semester project under Dietrich College of Humanities and Social Sciences Senior Honors Thesis Program and the Expeditions grant, which aims to help the understanding of the flow of information and levels of communication of caregivers associated with a classroom for 4-7 year old children with special needs, behavior problems and/ or diagnosed with Autism Spectrum Disorder (ASD), enrolled in an Alternative School Placement (ASP) at Programs for Living, Education and Advocacy (PLEA), Pittsburgh.

Through a series of in-class observations and interviews with the educators, it seeks to advance insight into the frequency and value of communication between the educators, parents and other involved caregivers of the children.

The information gained will be utilized to inform the development of processes and technology in the future, which can assist these caregivers in their ability to provide for the children.

Predictive Patterns of Sex Trafficking Online

Emily Kennedy — Fri, 26 Oct 2012 13:37:20 PDT

In the past 10-15 years, the internet has become a popular tool for sex traffickers to advertise and sell their victims. For instance, there are thousands of posts each month selling sex on the common classifieds website Backpage.com, some of which may be cases of sex trafficking. I extracted this publicly available data from the U.S. cities represented on Backpage.com. I then used software developed at Carnegie Mellon’s Auton Lab to find out if it is possible to detect patterns emerging from the data available in sex ads, such as patterns of travel that traffickers may use. To help identify which posts are more likely to be cases of trafficking, I relied on guidance from law enforcement experts. The research in this paper shows that it is in theory possible to track the movement of similar posts—and therefore, similar pimps or victims—across the country over time. With further development and refinement, the techniques demonstrated in this thesis could become the foundation for a valuable tool for law enforcement to use to prosecute traffickers and rescue victims.

An aquarium made from fish soup

Caroline Kessler — Fri, 26 Oct 2012 13:37:18 PDT

Effects of Multiple Inputs with an Accent Cue in Speech Segmentation Facilitated by Language Experiences

Haesung Kim — Fri, 26 Oct 2012 13:37:17 PDT

Past studies using artificial language speech streams showed that adults use statistics to correctly segment words. However, these studies mostly used only a single stream input and monolingual populations. Given the number of bilinguals and the prevalence of exposures to multiple languages, how do monolinguals and bilinguals compare in speech segmentation task given multiple inputs? Speech segmentation becomes challenging with multiple inputs when learners combine input across languages. The statistics of particular units that overlap different languages may change and hinder correct segmentation. Current study addresses this question by using two interleaved artificial language streams and an indexical accent cue. In the study, participants were asked to segment two artificial language streams with or without an accent cue. Our results indicated that in the absent of the accent cue, bilinguals and monolinguals performed similar, while monolinguals’ performance was weakened compared to those of bilinguals in the presence of the accent cue. Weakened performance can be due to two accounts: switching of accents and difficulty of languages. This study, expanding Weiss et al. (2009) and bilingualism research, informs us that the level of difficulty of languages and cues can play a role in segmenting multiple language streams.

Learning from La Vara: Shaping Sephardic Identity in New York City after the Second Diaspora

Kristen M. Minno — Fri, 26 Oct 2012 13:37:13 PDT

In New York City, the Sephardic immigrant community had established a strong foothold by the 1930s. However, the children of these immigrants were not learning traditions of their old homelands, or of centuries-old aspects of Sephardic culture. In response to this situation, Albert Levy, editor of the Sephardic newspaper La Vara, recognized that he and his paper could help to build bridges between the first generation immigrants from the Second Diaspora and their American children. Thus, on August 31, 1934, Levy published the first English section page in La Vara, which had previously been printed exclusively in the Ladino language in Hebrew characters. The main goal of this page was to reach out to Sephardic youth who were increasingly primary English speakers. This strategic move to English succeeded in creating an open arena for Sephardic youth to gain access to Jewish, and more importantly Sephardic, issues. These issues led to the ultimate formation of their unique identity, which centered on access to education; the lack of unity among Jews in New York; concerns about anti-Semitism; concerns about nationalism; an interest in strong historical ties to other world Jewish communities; and cultivating Jewish-American identity as well as connections to the Hispanic community in the metropolitan region. This paper explores the complicated question of the identity of Sephardic American Jews based on the issues raised by La Vara, and discusses how and why Sephardic identity changed over time.

Optimal Decision Making in Interdependent Network Security

Alan Nochenson — Fri, 26 Oct 2012 13:37:07 PDT

Although people are frequently urged to protect the machines they use and oversee, the fact remains that the decision to invest in protection software is far from universal. To better understand this decision, we formulate two models of interdependent network security. In the first, there is a system administrator responsible for a network of size n against attackers attempting to penetrate the network and infect the machines with viruses or other exploits. Through analysis of this interdependent network security scenario, we conclude that the decision to buy protection is dependent upon a number of factors including external and internal vulnerabilities, the types and likelihoods of different amounts of loss, the degree of autonomy of the attacker, and others.

The second model looks at network security from a game-theoretic point of view. Through the formulation and examination of increasingly complex scenarios, we formulate a model for utility-based security decisions for an individual in a network of individuals. We look at the decision for one person buy security software for herself and to buy security software in the context of two or more people. By modeling security as a public good, we examine externalities that players impose upon each other. We then examine Olson's theory of groups [13] in a network security context to evaluate the effect of network size on optimal decision-making. Network topologies are also discussed to investigate the limitations of the common game-theoretic interdependent security models. We conclude that these models work well for small to medium-sized networks with fairly uniform topologies. Through analysis of these two models, we propose methodologies for decision-making that are simple to understand and applicable to many other interdependent security scenarios.

Rediscovering Space: The Rise and Fall of the Congressional Space Caucus, 1981‐1989

Jacqueline Cortese — Fri, 26 Oct 2012 08:11:57 PDT

The 1970s and 1980s witnessed the birth, development, and subsequent multiplication of congressional caucuses, which have adapted and evolved over several decades into powerful, unofficial, congressional institutions. Despite their importance to the broader congressional system, caucuses have received little scholarly attention. Author Susan Webb Hammond published the most thorough and substantive study to date, entitled Congressional Caucuses in National Policymaking (1998). According to Hammond, the traditional congressional structure was unable to respond effectively to the “changes in the polity” that arose during this time period, leading to the emergence of congressional caucuses. The central change came when “an increasing number of complex, crosscutting, and interconnected issues began to occupy the congressional agenda.” Hammond provides the example of the environment as a growing topic of national attention that simultaneously raised concerns for health, economics, and several other intersecting areas. Congress grew increasingly ineffective in handling these issues that began falling “into jurisdictional cracks” or were dispersed across several committees and subcommittees.

How Adults Understand and Reason about Fractions

Melissa DeWolf — Fri, 26 Oct 2012 08:11:56 PDT

We investigated what strategies adults use to compare magnitudes of fractions, and how the strategies vary with overall mathematical knowledge. Because little is known about how people think about fractions, prior research has attempted to assess the extent to which people think of fractions compared to how they think about whole numbers (Bonato, Fabbri, Umilta & Zorzi, 2007; Schneider & Siegler, 2010; Meert, Gregoire, Noel, 2009). In particular, Bonato et al. (2007) has examined the degree to which fractional magnitude comparisons can yield an understanding of the mental representation of fractions. Schneider & Siegler (2010) argue that these assessments cannot be made independently from understanding the strategies for comparison that a particular pair of fractions elicits. The current study extends prior research by comparing fraction magnitude comparison strategies of students at a selective university, with high math proficiency, with those of students at a community college, with lower math proficiency. The goals of this thesis were to identify, explain and define the strategies that are used in fraction magnitude comparisons by adults, investigate how these strategies vary with the math proficiency of the adults, and evaluate whether adults who do not consistently use desirable strategies recognize desirability of good alternative strategies. Our findings indicate that strategy use and consistency of using good and poor strategies vary with overall math knowledge and performance on our magnitude comparison task; that lower performing participants more frequently used strategies that would yield incorrect results and less often recognize when to switch to good alternative strategies compared to the high performing participants.