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Title: Estimation of Platinum Oxide Degradation in Proton Exchange Membrane Fuel Cells
Creator: Ahmed, Niyaz Afnan
Date: 2024
Description: The performance and durability of Proton Exchange Membrane Fuel Cells (PEMFCs) can be significantly hampered due to the degradation of the...
Show moreThe performance and durability of Proton Exchange Membrane Fuel Cells (PEMFCs) can be significantly hampered due to the degradation of the platinum catalyst. The production of platinum oxide is a major cause of the degradation of the fuel cell system, negatively affecting its performance and durability. In order to predict and prevent this degradation, this research examines a novel method to estimate degradation due to platinum oxide formation and predict the level of platinum oxide coverage over time. Mechanisms of platinum oxide formation are outlined and two methods are compared for platinum oxide estimation. Linear regression and two Artificial Neural Network (ANN) models, including a Recurrent Neural Network (RNN) and Feed-forward Back Propagation Neural Network (FFBPNN), are compared for estimation. The estimation model takes into account the influence of cell temperature and relative humidity.Evaluation of relative errors (RE) and root mean square error (RMSE) illustrates the superior performance of RNN in contrast to GT-Suite and FFBPNN. However, both RNN and GT-Suite showcase an average error rate below 5% while the FFBPNN had a higher error rate of approximately 7%. The RMSE of RNN shows mostly less compared to FFBPNN and GT-Suite, however, at 50% training data, GT-Suite shows lowest RMSE. These findings indicate that GT-Suite can be a valuable tool for estimating platinum oxide in fuel cells with a relatively low RE, but the RNN model may be more suitable for real-time estimation of platinum oxide degradation in PEM fuel cells, due to its accurate predictions and shorter computational time. This comprehensive approach provides crucial insights for optimizing fuel cell efficiency and implementing effective maintenance strategies.
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Title: The Voderettes: Gender, Labor, and Techno-Utopia at the 1939 New York World's Fair
Creator: Simon, Sara M. B.
Date: 2024
Description: This thesis explores the labor demands of the Voder, the electrical speech synthesis machine developed by Bell Labs to be a major component of...
Show moreThis thesis explores the labor demands of the Voder, the electrical speech synthesis machine developed by Bell Labs to be a major component of AT&T's 1939 New York World's Fair exhibit. With the United States emerging from the Great Depression, and with political tensions escalating across the globe, the paper situates the Voder's labor demands within the historical context of the fair. Specifically, I explore the decision to have young women operate the Voder, the intricacies of the machine cloaked by the warm presence of its highly-skilled female operator. Using archival records from Bell Labs engineers, the paper exposes the previously unacknowledged engineering contributions of Voder operators in the years before the fair. These young women not only influenced major decisions about the Voder's mechanics but also gave early credence to the notion that developing a performance with the machine could make for a thrilling fair exhibit. Moreover, the paper argues that at the fair itself, AT&T and Bell Labs executives used the Voder operators to normalize a new vision of a technological utopia that relied heavily and conspicuously on the infrastructural labor of women. Given the Voder's legacy, as a tool that laid critical groundwork for voice encryption technology, the paper adds important context to the historical record, highlighting the young women at the heart of the machine.
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Title: Agency and Pathway Thinking as Mediators of The Relationship Between Caregiver Burden And Life Satisfaction Among Family Caregivers Of People With Parkinson’s Disease: An Application Of Snyder’s Hope Theory
Creator: Springer, Jessica Gabrielle
Date: 2024
Description: In the United States, there are 47.9 million caregivers providing care to family members with disabilities. Those providing care to someone...
Show moreIn the United States, there are 47.9 million caregivers providing care to family members with disabilities. Those providing care to someone who has Parkinson’s Disease (PD), a complex degenerative movement disorder, may have a unique caregiving experience, given that disease-related factors (e.g. motor and non-motor symptoms) can contribute to worsening caregiver burden and life satisfactions (LS). PD has an increasing incidence of 90,000 new cases per year, likely resulting in an increased need for caregivers. Caregiving research frequently focuses on the mediators between caregiver burden and LS including social support, coping skills, and appraisals. Research that has specifically focused on caregivers of people with PD (Pw/PD) is significantly limited. Hope is a “positive motivational characteristic comprised of agency and pathways thinking that can help facilitate drive towards one’s goal while also serving as a buffer against negative events” (Snyder et al.,1991). The goal of this study is to understand Snyder’s hope theory as it relates to caregiver burden and LS for caregivers of Pw/PD. Specifically, we hypothesized that (a) caregiver burden will be negatively correlated with agency thinking, pathways thinking, and LS among caregivers of Pw/PD. In addition, pathways thinking, and agency thinking will be positively associated with LS, and (b) agency thinking, and pathways thinking will mediate the relationship between caregiver burden and LS among caregivers of Pw/PD. The study sample consisted of 249 caregivers of Pw/PD who completed an online anonymous questionnaire. Correlations between agency and pathways thinking, LS, caregiver burden, and sociodemographic factors were evaluated. A parallel mediation analysis was run to evaluate the mediating roles of pathways and agency thinking in the relationship between caregiver burden and LS. Results indicated that LS was significantly and negatively correlated with caregiver burden. LS was significantly and positively correlated with both pathways and agency thinking. Pathways thinking had no indirect effect on the relationship of caregiver burden on LS. Agency thinking had a negative, indirect effect on the relationship suggesting that agency thinking partially mediated the relationship between caregiver burden and LS. Clinical implications and future directions are discussed.
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Title: Three-Dimensional Co-Culture Systems for Vascularization of Cardiac Tissue
Creator: Rodriguez Arias, Jessica A.
Date: 2023
Description: Myocardial Infarction (MI) is the partial or complete blockage of blood flow to the myocardial tissue resulting in damage and therefore loss...
Show moreMyocardial Infarction (MI) is the partial or complete blockage of blood flow to the myocardial tissue resulting in damage and therefore loss of heart function. In the U.S. every 40 seconds, someone will suffer from MI and the only available treatment is medication to treat the symptoms of heart function loss, but do not treat the underlying cause. Some attempts to treat the underlying cause have arisen in the last decades including cell-based therapies or tissue engineering therapies such as spheroid-based cardiac patches that have shown to be promising. Improvement in the mechanical properties to create suturable engineered tissues remain to be improved for ease of implantation purposes. Cell-laden hydrogel scaffolds can provide improved mechanical properties compared to biomaterial free cell-based therapies but need to allow for vascularization of the engineered tissue. Thus, the goal of this thesis is to provide preliminary studies for the use of a cell adhesive, proteolytically degradable PEG hydrogel scaffold that eventually would be used as an invitro model to evaluate engineered tissue vascularization for cardiac tissue engineering. To construct this model, important cell spheroid parameters on vascular invasion in 3D culture were investigated including the total number of cells/spheroid, the supporting cell for endothelial cells. In order to scale-up scaffolds to size of clinically relevant dimensions, a multilayered hydrogel construct visible light free-radical polymerization approach encapsulating vascular spheroids in multiple layers was also investigated. Results indicate that a total cell number of 5000 cells/spheroid aggregate were feasible due to cell sourcing. In addition, co-cultures of endothelial and mesenchymal stem cells led to maximized vascular invasion of the spheroids compared to fibroblast/endothelial co-culture and endothelial monoculture of spheroids in the hydrogel. Finally, the extent of vascularization of spheroids in each layer of the multilayered hydrogel constructs varied due to the observed differences in mechanical properties and swelling ratio of each layer due to incomplete polymerization of layers. This study demonstrated the importance of support cells and hydrogel mechanical properties in promoting vascularization of spheroid which serves as basis for building cell-laden hydrogel scaffolds for vascularization for cardiac tissues.
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Title: Pilgrim Baptist Church, Chicago, Illinois, ca. 1964
Creator: Weil, F. Peter
Date: 1952-1964
Description: Pilgrim Baptist Church (3301 S. Indiana Ave, Chicago, IL) photographed from the northwest by Institute of Design student F. Peter Weil. Date...
Show morePilgrim Baptist Church (3301 S. Indiana Ave, Chicago, IL) photographed from the northwest by Institute of Design student F. Peter Weil. Date is estimated as 1964 from other evidence in the collection.
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Collection: F. Peter Weil photographs, 1952-1964

Title: Technology News, January 10, 1944
Creator: Illinois Institute of Technology
Date: 1944-01-10, 1944-01-10
Collection: Technology News Microfilm collection, 1928-1981

Title: Population Dynamics of Listeria monocytogenes in Nut, Seed and Legume Butters
Creator: Zhang, Xinyuan
Date: 2020
Description: Nut, seed, and legume butters are low water activity foods and do not support the growth of foodborne pathogens. Research has determined that...
Show moreNut, seed, and legume butters are low water activity foods and do not support the growth of foodborne pathogens. Research has determined that some pathogens, such as Listeria monocytogenes, can survive for long periods of time in butters, such as almond butter. However, information on the persistence of L. monocytogenes in butters is lacking. The purpose of this study was to determine the population dynamics of L. monocytogenes in butters stored at 5 and 25°C. Nut (almond, hazelnut, pecan), seed (pumpkin, sesame, sunflower), legume (peanut and soy) and butters containing chocolate (hazelnut and peanut) were inoculated with a 4-strain cocktail of rifampicin-resistant L. monocytogenes at 4 (high inoculation) or 1 log CFU/g (low inoculation). High inoculation butters were mixed by hand for 15 min and 100-g portions were weighed into deli-style containers with lids and stored at 5 or 25°C for 12 mo (370 d). Low inoculation butters were stored in 25- g portions in stomacher bags at 25°C for 6 mo (180 d). During storage, 25 g from the 100- g high inoculation portion or 25 g from the low inoculation samples, in triplicate, were homogenized with 225 mL BPB (or BLEB for FDA BAM enrichments when necessary) and serial dilutions of the homogenate were plated onto BHIA with rifampicin for enumeration of L. monocytogenes. Data were statistically analyzed using Student’s t-test (α=0.05). The average initial population of L. monocytogenes in the butters was 3.58±0.25 log CFU/g for the high inoculation butters; L. monocytogenes was detected through enrichments for all low inoculation butters. After 12 mo storage at 5°C, the population of L. monocytogenes decreased by 1.34, 1.27, 1.72, 2.04 and 0.93 log CFU/g in almond, hazelnut, peanut with chocolate, hazelnut with chocolate and pecan butter, respectively, when inoculated at the higher level. Significantly less population reduction was observed in pumpkin, sesame, soy, peanut and sunflower butters (1.08, 0.61, 0.84, 0.05 and 0.40 log CFU/g, respectively). After 12 mo storage at 25°C, the L. monocytogenes population in all butters, with the exception of sunflower butter, decreased to below the limit of enumeration (1.67 log CFU/g), but the pathogen was still present via enrichment. For low inoculation butters, L. monocytogenes was present as determined by enrichment in all butters in at least one of two trials after 6 mo. The results of this study provide information on the survival of L. monocytogenes in different butter types when stored at different temperatures.
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Title: Photograph of the Aaron Galleries booth at the Modernism art fair, including Mary Henry's Quasar, New York, New York, 2006
Date: 2006
Description: Photograph of the Aaron Galleries Booth at the Modernism exhibition, at Park Place Armory in 2006, including Mary Henry's painting Quasar....
Show morePhotograph of the Aaron Galleries Booth at the Modernism exhibition, at Park Place Armory in 2006, including Mary Henry's painting Quasar. Aaron Brothers, a Chicago gallery, included Mary Henry's work in two art shows at Park Place Armory in 2006, Modernism and Art20. Inscription on verso: "Modernism - Park Avenue Armory 2006 Mary Henry 'Quasar' in booth center Aaron Galleries, Exhibitor." Photographer unknown.
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Collection: Mary Dill Henry Papers, 1913-2021

Title: Photograph of the Aaron Galleries booth at the Modernism art fair, including Mary Henry's Quasar, New York, New York, 2006
Date: 2006
Description: Photograph of the Aaron Galleries Booth at the Modernism exhibition, at Park Place Armory in 2006, including Mary Henry's painting Quasar....
Show morePhotograph of the Aaron Galleries Booth at the Modernism exhibition, at Park Place Armory in 2006, including Mary Henry's painting Quasar. Aaron Brothers, a Chicago gallery, included Mary Henry's work in two art shows at Park Place Armory in 2006, Modernism and Art20. Inscription on verso: "Modernism - Park Avenue Armory 2006 Mary Henry 'Quasar' in booth center Aaron Galleries, Exhibitor." Photographer unknown.
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Collection: Mary Dill Henry Papers, 1913-2021

Title: Photograph of the Aaron Galleries booth at the Modernism art fair, including Mary Henry's Quasar, New York, New York, 2006
Date: 2006
Description: Photograph of the Aaron Galleries Booth at the Modernism exhibition, at Park Place Armory in 2006, including Mary Henry's painting Quasar....
Show morePhotograph of the Aaron Galleries Booth at the Modernism exhibition, at Park Place Armory in 2006, including Mary Henry's painting Quasar. Aaron Brothers, a Chicago gallery, included Mary Henry's work in two art shows at Park Place Armory in 2006, Modernism and Art20. Inscription on verso: "Modernism - Park Avenue Armory 2006 Mary Henry 'Quasar' in booth center Aaron Galleries, Exhibitor." Photographer unknown.
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Collection: Mary Dill Henry Papers, 1913-2021

Title: Photograph of the Aaron Galleries booth at the Modernism art fair, including Mary Henry's Quasar, New York, New York, 2006
Date: 2006
Description: Photograph of the Aaron Galleries Booth at the Modernism exhibition, at Park Place Armory in 2006, including Mary Henry's painting Quasar....
Show morePhotograph of the Aaron Galleries Booth at the Modernism exhibition, at Park Place Armory in 2006, including Mary Henry's painting Quasar. Aaron Brothers, a Chicago gallery, included Mary Henry's work in two art shows at Park Place Armory in 2006, Modernism and Art20. Inscription on verso: "Modernism - Park Avenue Armory 2006 Mary Henry 'Quasar' in booth center Aaron Galleries, Exhibitor." Photographer unknown.
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Collection: Mary Dill Henry Papers, 1913-2021

Title: Photograph of the Aaron Galleries booth at the Modernism art fair, including Mary Henry's Quasar, New York, New York, 2006
Date: 2006
Description: Photograph of the Aaron Galleries Booth at the Modernism exhibition, at Park Place Armory in 2006, including Mary Henry's painting Quasar....
Show morePhotograph of the Aaron Galleries Booth at the Modernism exhibition, at Park Place Armory in 2006, including Mary Henry's painting Quasar. Aaron Brothers, a Chicago gallery, included Mary Henry's work in two art shows at Park Place Armory in 2006, Modernism and Art20. Inscription on verso: "Modernism - Park Avenue Armory 2006 Mary Henry 'Quasar' in booth center Aaron Galleries, Exhibitor." Photographer unknown.
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Collection: Mary Dill Henry Papers, 1913-2021

Title: Photograph of the Aaron Galleries booth at the Modernism art fair, including Mary Henry's Quasar, New York, New York, 2006
Date: 2006
Description: Photograph of the Aaron Galleries Booth at the Modernism exhibition, at Park Place Armory in 2006, including Mary Henry's painting Quasar....
Show morePhotograph of the Aaron Galleries Booth at the Modernism exhibition, at Park Place Armory in 2006, including Mary Henry's painting Quasar. Aaron Brothers, a Chicago gallery, included Mary Henry's work in two art shows at Park Place Armory in 2006, Modernism and Art20. Inscription on verso: "Modernism - Park Avenue Armory 2006 Mary Henry 'Quasar' in booth center Aaron Galleries, Exhibitor." Photographer unknown.
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Collection: Mary Dill Henry Papers, 1913-2021

Title: Photograph of the Aaron Galleries booth at the Modernism art fair, including Mary Henry's Quasar, New York, New York, 2006
Date: 2006
Description: Photograph of the Aaron Galleries Booth at the Modernism exhibition, at Park Place Armory in 2006, including Mary Henry's painting Quasar....
Show morePhotograph of the Aaron Galleries Booth at the Modernism exhibition, at Park Place Armory in 2006, including Mary Henry's painting Quasar. Aaron Brothers, a Chicago gallery, included Mary Henry's work in two art shows at Park Place Armory in 2006, Modernism and Art20. Inscription on verso: "Modernism - Park Avenue Armory 2006 Mary Henry 'Quasar' in booth center Aaron Galleries, Exhibitor." Photographer unknown.
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Collection: Mary Dill Henry Papers, 1913-2021

Title: Photograph of the Aaron Galleries booth at the Modernism art fair, including Mary Henry's Quasar, New York, New York, 2006
Date: 2006
Description: Photograph of the Aaron Galleries Booth at the Modernism exhibition, at Park Place Armory in 2006, including Mary Henry's painting Quasar....
Show morePhotograph of the Aaron Galleries Booth at the Modernism exhibition, at Park Place Armory in 2006, including Mary Henry's painting Quasar. Aaron Brothers, a Chicago gallery, included Mary Henry's work in two art shows at Park Place Armory in 2006, Modernism and Art20. Inscription on verso: "Modernism - Park Avenue Armory 2006 Mary Henry 'Quasar' in booth center Aaron Galleries, Exhibitor." Photographer unknown.
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Collection: Mary Dill Henry Papers, 1913-2021

Title: Photograph of the Aaron Galleries booth at the Art 20 art fair, including Mary Henry's The Chelsea Way, New York, New York, 2006
Date: 2006
Description: Photograph of the Aaron Galleries Booth at the Art 20 exhibition, at Park Place Armory in 2006, including Mary Henry's painting The Chelsea...
Show morePhotograph of the Aaron Galleries Booth at the Art 20 exhibition, at Park Place Armory in 2006, including Mary Henry's painting The Chelsea Way visible at right. Inscription on verso: "Art 20 - Park Ave. Armory 2006 Mary Henry 'The Chelsea Way' on the aisle Aaron Galleries Booth."
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Collection: Mary Dill Henry Papers, 1913-2021

Title: TechNews, March 29, 2011
Creator: Illinois Institute of Technology
Date: 2011-03-29, 2011-03-29
Collection: Technology News print collection, 1940-2019

Title: Intraoperative Assessment of Surgical Margins in Head And Neck Cancer Resection Using Time-Domain Fluorescence Imaging
Creator: Cleary, Brandon M.
Date: 2023
Description: Rapid and accurate determination of surgical margin depth in fluorescence guided surgery has been a difficult issue to overcome, leading to...
Show moreRapid and accurate determination of surgical margin depth in fluorescence guided surgery has been a difficult issue to overcome, leading to over- or under-resection of cancerous tissues and follow-up treatments such as ‘call-back’ surgery and chemotherapy. Current techniques utilizing direct measurement of tumor margins in frozen section pathology are slow, which can prevent surgeons from acting on information before a patient is sent home. Other fluorescence techniques require the measurement of margins via captured images that are overlayed with fluorescent data. This method is flawed, as measuring depth from captured images loses spatial information. Intensity-based fluorescence techniques utilizing tumor-to-background ratios do not decouple the effects of concentration from the depth information acquired. Thus, it is necessary to perform an objective measurement to determine depths of surgical margins. This thesis focuses on the theory, device design, simulation development, and overall viability of time-domain fluorescence imaging as an alternative method of determining surgical margin depths. Characteristic regressions were generated using a thresholding method on acquired time-domain fluorescence signals, which were used to convert time-domain data to a depth value. These were applied to an image space to generate a depth map of a modelled tissue sample. All modeling was performed on homogeneous media using Monte Carlo simulations, providing high accuracy at the cost of increased computational time. In practice, the imaging process should be completed within a span of under 20 minutes for a full tissue sample, rather than 20 minutes for a single slice of the sample. This thesis also explores the effects of different thresholding levels on the accuracy of depth determination, as well as the precautions to be taken regarding hardware limitations and signal noise.
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Title: Improving Niobium Superconducting Radio-Frequency Cavities by Studying Tantalum
Creator: Helfrich, Halle
Date: 2023
Description: Niobium superconducting radio-frequency (SRF) cavities are widely used accelerating structures. Improvements in both quality factor, Q0, and...
Show moreNiobium superconducting radio-frequency (SRF) cavities are widely used accelerating structures. Improvements in both quality factor, Q0, and maximum accelerating gradient, Eacc, have been made to SRF cavities by introducing new processing techniques. These breakthroughs include processes such as nitrogen doping(N-Doping) and infusion, electrochemical polishing (EP) and High Pressure Rinsing (HPR). [1] There is still abundant opportunity to improve the cavities or, rather, the material they’re primarily composed of: niobium. A focus here is the role the native oxide of Nb plays in SRF cavity performance. The values of interest in a given cavity are its quality factor Q0, maximum accelerating gradient Eacc and surface resistance Rs . This work characterizes Nb and Ta foils prepared under identical conditions using X-ray photoelectron spectroscopy (XPS) to compare surface oxides and better understand RF loss mechanisms in Nb SRF cavities and qubits. It is well established that Ta qubits experience much longer coherence times than Nb qubits, which is probably due to the larger RF losses in Nb oxide. By studying Tantalum, an element similar to Niobium, the mechanisms of the losses that originate in the oxide and suboxide layers present on the surface of Nb cavities might finally be unlocked. We find noticeable differences in the oxides of Nb and Ta formed by air exposure of clean foils. In particular, Ta does not display the TaO2 suboxide in XPS, while Nb commonly shows NbO2. This suggests that suboxides are an additional contributor of RF losses. We also suggest that thin Ta film coatings of Nb SRF cavities may be a way of increasing Q0. It is in the interest of the accelerator community to fully understand the surface impurities present in Nb SRF cavities so that strategies for mitigating the effects can be proposed.
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Title: Independence and Graphical Models for Fitting Real Data
Creator: Cho, Jason Y.
Date: 2023
Description: Given some real life dataset where the attributes of the dataset take on categorical values, with corresponding r(1) × r(2) × … × r(m)...
Show moreGiven some real life dataset where the attributes of the dataset take on categorical values, with corresponding r(1) × r(2) × … × r(m) contingency table with nonzero rows or nonzero columns, we will be testing the goodness-of-fit of various independence models to the dataset using a variation of Metropolis-Hastings that uses Markov bases as a tool to get a Monte Carlo estimate of the p-value. This variation of Metropolis-Hastings can be found in Algorithm 3.1.1. Next we will consider the problem: ``out of all possible undirected graphical models each associated to some graph with m vertices that we test to fit on our dataset, which one best fits the dataset?" Here, the m attributes are labeled as vertices for the graph. We would have to conduct 2^(mC2) goodness-of-fit tests since there are 2^(mC2) possible undirected graphs on m vertices. Instead, we consider a backwards selection method likelihood-ratio test algorithm. We first start with the complete graph G = K(m), and call the corresponding undirected graphical model ℳ(G) as the parent model. Then for each edge e in E(G), we repeatedly apply the likelihood-ratio test to test the relative fit of the model ℳ(G-e), the child model, vs. ℳ(G), the parent model, where ℳ(G-e) ⊆ℳ(G). More details on this iterative process can be found in Algorithm 4.1.3. For our dataset, we will be using the alcohol dataset found in https://www.kaggle.com/datasets/sooyoungher/smoking-drinking-dataset, where the four attributes of the dataset we will use are ``Gender" (male, female), ``Age", ``Total cholesterol (mg/dL)", and ``Drinks alcohol or not?". After testing the goodness-of-fit of three independence models corresponding to the independence statements ``Gender vs Drink or not?", ``Age vs Drink or not?", and "Total cholesterol vs Drink or not?", we found that the data came from a distribution from the two independence models corresponding to``Age vs Drink or not?" and "Total cholesterol vs Drink or not?" And after applying the backwards selection likelihood-ratio method on the alcohol dataset, we found that the data came from a distribution from the undirected graphical model associated to the complete graph minus the edge {``Total cholesterol”, ``Drink or not?”}.
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