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Boulder Distribution Analysis Of Impact Craters In The Tharsis Region And Elysium Planitia, Mars, Nicole Button Dec 2017

Boulder Distribution Analysis Of Impact Craters In The Tharsis Region And Elysium Planitia, Mars, Nicole Button

LSU Master's Theses

Crater counting is an accepted method for dating the surface of a planetary body. An older landscape will have a higher areal density of craters due to exposure of impacts occurring over a longer time period. Since each initial impact only forms one primary crater, secondary craters need to be excluded in the crater counting method to appropriately catalog only distinct impact events. However, small primary craters may be difficult to distinguish from secondary craters. Understanding physical features of impact craters, such as the ejecta blanket, would improve the planetary community’s ability to differentiate between the two types of craters. …


A Study Of The Urban Red Fox (Vulpes Vulpes) Population In Baton Rouge, Louisiana Using Social Media, Ahsennur Soysal Nov 2017

A Study Of The Urban Red Fox (Vulpes Vulpes) Population In Baton Rouge, Louisiana Using Social Media, Ahsennur Soysal

LSU Master's Theses

Foxes are timid yet resourceful animals that are integrated into many urban environments. Because they are elusive, collecting information about the number of urban foxes, their diet and spatial distribution, their interactions with the ecological community in their urban habitat, as well as residents’ response to them, is difficult. Involving stakeholders to participate in the data collection on wildlife via citizen science on social media is one way to overcome this complication, while simultaneously engaging residents in the ecology happening around them. Therefore, we used social media as the platform to engage the public to document and map the foxes …


Evidence Of Subglacial Brine Inflow And Wind-Induced Mixing From High Resolution Temperature Measurements In Lake Bonney, Antarctica, Jade Lawrence Nov 2017

Evidence Of Subglacial Brine Inflow And Wind-Induced Mixing From High Resolution Temperature Measurements In Lake Bonney, Antarctica, Jade Lawrence

LSU Master's Theses

Hypersaline brine beneath Taylor Glacier enters proglacial West Lobe Lake Bonney (WLB) subglacially as well as from Blood Falls, a surface discharge point at the Taylor Glacier terminus. The brine strongly influences the water column of WLB. Because of the extremely high salinities below the chemocline in WLB, density is determined almost entirely by salinity and temperature can be used as a passive tracer. Cold brine intrusions enter WLB at the glacier face and intrude in to the water column at the depth of neutral buoyancy, where they can be identified by anomalously cold temperatures at that depth. This study …


Combining Downhole And Sediment Logging To Understand Spatial Variability In Grain-Size, Facies, And Reservoir Quality Of A Large-Scale Mississippi River Point Bar, False River, Louisiana, Elizabeth D. Olson Nov 2017

Combining Downhole And Sediment Logging To Understand Spatial Variability In Grain-Size, Facies, And Reservoir Quality Of A Large-Scale Mississippi River Point Bar, False River, Louisiana, Elizabeth D. Olson

LSU Master's Theses

Although the general processes by which meandering river point bars are constructed have been known for some time, there is a lack of clarity regarding why small-scale heterogeneities develop. This is especially true in the largest meandering river systems, which are equivalent to some of the most important hydrocarbon reservoirs in the world. In this study, we evaluate the stratigraphic architecture of the 80 km2 False River Point Bar System on the Lower Mississippi River and use the knowledge gained to better comprehend point bar construction at different phases. Previous studies of small to medium-scale systems have been unable …


Floodplain Impacts On Water Quality: A Case Study In Southern Louisiana, Emily Delduco Nov 2017

Floodplain Impacts On Water Quality: A Case Study In Southern Louisiana, Emily Delduco

LSU Master's Theses

The quantity and quality of dissolved carbon delivered to coastal margins by rivers is an important component of global carbon cycling. The Atchafalaya River (AR) discharges ~25% of the flow of the Mississippi River (MR) and the total flow of the Red River (RR) into the Gulf of Mexico (GoM) annually while flowing through the largest bottomland swamp in North America. This provides a unique opportunity to study floodplain impacts on dissolved carbon processes in a large river system. The research aimed to: (1) determine DIC and DOC transport and processing by a river swamp basin under varied seasons and …


Issues Related To Carbon Dioxide Pipeline Transportation Infrastructure In Louisiana, Michael Allen Layne Iii Nov 2017

Issues Related To Carbon Dioxide Pipeline Transportation Infrastructure In Louisiana, Michael Allen Layne Iii

LSU Master's Theses

There is no single solution to mitigate anthropogenic climate change; a multifaceted approach with economic incentives is needed. Carbon dioxide (CO2) enhanced oil recovery (EOR) is one such solution which provides an economic incentive, in the capture and sale of oil, for sequestering CO2 underground. While carbon capture and subsequent geological injection are both mature technologies, there has been little discussion or appreciation for the role of pipelines. The current CO2 pipeline infrastructure will need to significantly expand in order to accommodate increasing EOR production. However, pipeline construction costs, and institutional factors impacting development, may be …


How Dredge Pits Evolve Over Time: A Look At Their Geomorphologic Evolution And Infilling Processes, Patrick Robichaux Nov 2017

How Dredge Pits Evolve Over Time: A Look At Their Geomorphologic Evolution And Infilling Processes, Patrick Robichaux

LSU Master's Theses

As coastal environments become more susceptible to land loss through accelerating sea level rise and subsidence, new restoration methods harnessing borrowed sediment are more valuable than ever. Mud-capped dredge pits (MCDPs) are a relatively new source of restoration-quality sediment that has only recently been utilized for beach and barrier island restorations in Louisiana. Because MCDPs have been in use for less than two decades in only a handful sites, little is understood about their evolution over decadal timescales. To improve our understanding of MCDPs after they are dredged, we have conducted a suite of geophysical surveys including bathymetry, sidescan sonar, …


Overbank Deposition Of Sand And Mud Within Two Point Bars Bound By The Mississippi River Levee System: Implications For Coastal Restoration Sediment Budgets, Christopher Magliolo Oct 2017

Overbank Deposition Of Sand And Mud Within Two Point Bars Bound By The Mississippi River Levee System: Implications For Coastal Restoration Sediment Budgets, Christopher Magliolo

LSU Master's Theses

As ongoing Mississippi River sediment diversion projects are being developed and planned, the availability of sand and mud for use in the lower Mississippi River Delta is being calculated and budgeted. This project attempts to quantify the amount of sand and mud being lost from the lower Mississippi River past the Old River Control Structure in the remaining unleveed floodplains, an area that encompasses 270 km2. Two land masses were chosen along each bank of this reach of the Mississippi River: Raccourci Island (west bank) and the Cat Island National Wildlife Refuge (east bank). Seventeen sediment cores were …


Investigating Core Shale Depositional Environments Of Late Pennsylvanian Cyclothems Utilizing Geochemical Proxies To Test The Superestuarine Model, Bryce A. Mathis Aug 2017

Investigating Core Shale Depositional Environments Of Late Pennsylvanian Cyclothems Utilizing Geochemical Proxies To Test The Superestuarine Model, Bryce A. Mathis

LSU Master's Theses

The Late Paleozoic Midcontinent Sea (LPMS) inundated vast areas of the North American interior during glacio-eustatic transgressions, depositing widespread black shales facies within the core shale intervals of major cyclothems. These black shale deposits are unique because no modern analogs can adequately explain the depositional environments and model for organic matter preservation across such vast ancient epicontinental settings. One possible explanation is that a superestuarine circulation system developed across the LPMS during humid interglacial phases, which promoted strong water column stratification and benthic anoxia.

The goal of this research was to test the validity of the superestuarine estuarine model and …


Earthquake Risks In Haiti: An Analysis Of Response And Preparedness Strategies For The Design Of A New Mitigation Approach, Patrick Alteus Aug 2017

Earthquake Risks In Haiti: An Analysis Of Response And Preparedness Strategies For The Design Of A New Mitigation Approach, Patrick Alteus

LSU Master's Theses

Earthquakes can have enormous consequences on affected countries. To minimize these harsh consequences, an effective disaster management plan is necessary and a reasonable strategy is necessary to recover and get back to a normal life when they happen. Studies from scientists show that it is difficult to predict when an earthquake will occur. Because of this unpredictability, high-risk countries need to act continuously in order to deal with any sudden strike that may occur by stressing on the mitigation and preparedness activities and by designing appropriate response plans. In Haiti, a well-known earthquake-prone country, the preparedness and mitigation plans have …


Development Of The Focal Plane Instrumentation Of The Separator For Capture Reactions (Secar), Kyle Joerres Jan 2017

Development Of The Focal Plane Instrumentation Of The Separator For Capture Reactions (Secar), Kyle Joerres

LSU Master's Theses

The SEparator for CApture Reactions (SECAR) is currently being developed at the National Superconducting Cyclotron Laboratory (NSCL) and the future Facility for Rare Isotope Beams (FRIB) for measurements of nuclear reactions critical for understanding energy generation and element synthesis in stellar explosions. SECAR is an electromagnetic recoil separator designed for sensitive measurements of radiative capture reactions using beams of proton-rich, short-lived isotopes at the energies relevant for explosive environments such as Type I X-ray bursts and classical novae. SECAR is designed to efficiently separate capture reaction products of interest from the incident beam by up to a factor of 10^17 …


Palynostratigraphy And Environmental Implication Of Organic-Walled Microfossils Recovered From Iodp Site U1435, Mitchell Clifford Gregory Jan 2017

Palynostratigraphy And Environmental Implication Of Organic-Walled Microfossils Recovered From Iodp Site U1435, Mitchell Clifford Gregory

LSU Master's Theses

Extensive studies have examined the syn- and post-rift sediments in the South China Sea and surrounding margins, but pre-rift, Eocene deposits are rare. Here we examine organic-walled microfossils from the South China Sea, recovered at Site U1435 of IODP Expedition 349 to provide palynostratigraphic control and characterize the environmental setting before, and in response to, the initiation of seafloor spreading in the basin ~33 Ma. The well preserved palynological assemblage recovered allow dating of sediments sampled at Site U1435. Units II and III are now subdivided in 4 subzones; Zone 1 is essentially barren, Zones 2 and 3A are assigned …


Development And Application Of A Modis Inorganic Sediment Model During The 2016 Mississippi River Diversion In Lake Pontchartrain, Louisiana, Robert Lee Iles Iv Jan 2017

Development And Application Of A Modis Inorganic Sediment Model During The 2016 Mississippi River Diversion In Lake Pontchartrain, Louisiana, Robert Lee Iles Iv

LSU Master's Theses

The Bonnet Carré Spillway (BCS) is a Mississippi River diversion located on the southwestern coastline of Lake Pontchartrain in Louisiana. The discharge of potentially high amounts of Mississippi River nutrients and sediments during BCS diversion events has a noted ecological impact on the Lake Pontchartrain estuary. Projected river flooding prompted the opening of the Spillway from 10 January to 1 February 2016. MODIS satellite images were aerosol-corrected and then compared to in-situ measurements of inorganic sediment concentration (ISC) to derive a predictive algorithm for estimating ISC (in mg L^-1) in Lake Pontchartrain for satellite images in January and February. The …


The Effectiveness Of Isco Injection Methods For Remediation Of Groundwater, Matthew Ryan Vidrine Jan 2017

The Effectiveness Of Isco Injection Methods For Remediation Of Groundwater, Matthew Ryan Vidrine

LSU Master's Theses

In-Situ Chemical Oxidation (ISCO) injections were performed at Petro Stopping Centers # 10 (Petro) in December 2013 and June 2015. The methodology was direct injection of a heavy oxidizer, RegenOx®, followed by a time-release oxygen compound, ORC Advanced®, into a plume of gasoline sitting on top of the water in the aquifer in hope that this remediate the aquifer. Both chemicals are registered trademarks of the Regenesis® Company. The levels of contaminates have dropped considerably. However, Petro has not achieved closure criteria according to RECAP standards. The site is classified as a GW-1B, subject to the most stringent of remediation …


Interactive Web-Based Visualization Of Atomic Position-Time Series Data, Simron Thapa Jan 2017

Interactive Web-Based Visualization Of Atomic Position-Time Series Data, Simron Thapa

LSU Master's Theses

Extracting and interpreting the information contained in large sets of time-varying three dimensional positional data for the constituent atoms of simulated material system is a challenging task. This thesis work reports our initial implementation of a web-based visualization system and its use-case study. The system allows the users to perform the desired visualization task on a web browser for the position-time series data extracted from the local or remote hosts. It involves a pre-processing step for data reduction, which involves skipping uninteresting parts of the data uniformly (at full atomic configuration level) or non-uniformly (at atomic species level or individual …


Differential Responses Of Soil Greenhouse Gas Production And Denitrification To Salinity Alterations Along A Wetland Salinity Gradient, Natalie Ceresnak Jan 2017

Differential Responses Of Soil Greenhouse Gas Production And Denitrification To Salinity Alterations Along A Wetland Salinity Gradient, Natalie Ceresnak

LSU Master's Theses

Coastal wetlands provide several valuable services, such as carbon (C) storage and nitrogen (N) removal. Although wetlands serve as net C sinks, wetland soils release greenhouse gases (GHGs) including carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). Wetlands can buffer the influx of nitrate (NO3-) by transforming it into gaseous N (N2O, N2) through denitrification microbial pathway. Salinity is a regulator of soil biogeochemistry and long- (e.g. saltwater intrusion) and short-term (e.g. storm surges, river diversions) exposures may affect soil GHG production and denitrification. In this study, soil GHG production and denitrification enzyme activity (DEA) rates were examined over …


Microseismic Event Characteristics Associated With The Spatial And Temporal Stages Of Hydraulic Fracture Growth In Laboratory Experiments, Abigail Arielle Maxwell Jan 2017

Microseismic Event Characteristics Associated With The Spatial And Temporal Stages Of Hydraulic Fracture Growth In Laboratory Experiments, Abigail Arielle Maxwell

LSU Master's Theses

There are uncertainties in the exact mechanisms that occur during hydraulic fracture growth and the interactions of hydraulic fractures with pre-existing fractures. In some cases fracture growth is seen to be purely tensile and in others a combination of tensile and shear mechanisms. In order to develop a seismic model to explain fracture propagation, there is a need for a complete classification of the microseismic events occurring during fracturing using waveform characteristics such as frequency, duration and magnitude. This classification would allow for more accurate prediction of the behavior of the hydraulic fracture from its initiation to when it intersects …


On-Site Sperm Cryopreservation For Aquatic Repository Development And User Group Linkage, William Martin Childress Jan 2017

On-Site Sperm Cryopreservation For Aquatic Repository Development And User Group Linkage, William Martin Childress

LSU Master's Theses

Although on-site cryopreservation of aquatic species sperm in nitrogen-vapor shipping dewars has been used for more than 30 yr, many limitations remain. Due to the size of shipping dewars, most studies are small scale and can only produce tens of samples. The freezing temperatures that can be achieved are also affected by the size of the dewar and the number of samples being frozen due to the heat load. In addition, often due to timing or remote location these samples cannot be shipped, and if they are shipped, quality can be lost and the samples must be discarded. The goal …


Pesticide Concentrations In Water From A Southern Louisiana Marsh Influenced By The Mississippi River, Kara Leigh Callicott Jan 2017

Pesticide Concentrations In Water From A Southern Louisiana Marsh Influenced By The Mississippi River, Kara Leigh Callicott

LSU Master's Theses

The pesticides atrazine, chlorothalonil, and fipronil are common surface water contaminants due to their high rates of application and their chemical properties. This study investigates the introduction of contaminants into coastal wetlands via the Bayou Lamoque Mississippi River control structure in Plaquemines Parish, Louisiana. A protocol for environmental sampling using Continuous Low-level Aquatic Monitoring (C.L.A.M.) C-18 disks is described, along with effective solid phase extraction (SPE) and gas chromatography mass spectrometry (GC/MS) methodology for the determination of atrazine, chlorothalonil, and fipronil in surface water. Average concentrations of atrazine and chlorothalonil inside the Bayou Lamoque freshwater diversion structure for the months …


Modeling The Influence Of Energy And Climate Megatrends On Future Costs And Benefits Of Marsh Creation In The Mississippi Delta, Adrian R. H. Wiegman Jan 2017

Modeling The Influence Of Energy And Climate Megatrends On Future Costs And Benefits Of Marsh Creation In The Mississippi Delta, Adrian R. H. Wiegman

LSU Master's Theses

Over 25% of Mississippi delta (MRDP) wetlands were lost over the past century. There is currently a major effort to restore the MRDP focused on a 50-year time horizon, a period during which the energy system and climate will change dramatically. I modeled hydraulic dredging to sustain marsh from 2016-2066 and 2016-2100 under a range of scenarios for sea level rise, energy price, and management regimes. A marsh elevation model was calibrated to data from MRDP marshes. I developed a model to simulate dredging costs based on the price of crude oil and a project efficiency factor. Crude oil prices …


Measuring The Effects Of Recycled Water On The Growth Of Three Algal Species: Tisochrysis Lutea, Chaetcoeros Calcitrans, And C. Muelleri In A Commercial-Scale Oyster Hatchery, Lisa Marie Bourassa Jan 2017

Measuring The Effects Of Recycled Water On The Growth Of Three Algal Species: Tisochrysis Lutea, Chaetcoeros Calcitrans, And C. Muelleri In A Commercial-Scale Oyster Hatchery, Lisa Marie Bourassa

LSU Master's Theses

Algal production is often the limiting factor in large-scale oyster hatcheries, and constant, reliable production is required to grow enough algae to support all oyster larvae and broodstock grown and conditioned in a hatchery. The algal rooms in the Michael C. Voisin Oyster Hatchery at Grand Isle, LA are temperature-controlled to maintain consistent temperature, but this hatchery is also unique in its ability to recycle natural seawater pumped from the northern Gulf of Mexico. Effects of recycling seawater on algal production in an oyster hatchery, however, are undocumented. In this study, Tisochrysis lutea, Chaetoceros calcitrans and C. muelleri were grown …


Shallow Shear-Wave Seismic Analysis Of Point Bar Deposits Of False River, Louisiana, Martial James Morrison Jan 2017

Shallow Shear-Wave Seismic Analysis Of Point Bar Deposits Of False River, Louisiana, Martial James Morrison

LSU Master's Theses

Current point-bar complex models do not include subsurface unit bars as a normal feature. This study provides evidence for a potential buried unit bar amongst point-bar sediments of the large-scale, modern-day False River point-bar complex of the Mississippi River. We collect, process and interpret a two-dimensional, 150-m-long CMP seismic reflection profile that cuts perpendicularly across a major discontinuity surface in the False River point bar complex. The seismic source consists of a ground recoil device that fires a shotgun shell horizontally, producing shear waves. Multiple field experiments demonstrated which type of source and receiver provided the least amount of noise, …


Development Of A Low-Energy Monoenergetic Electron Separator, Sergio Martín López Cáceres Jan 2017

Development Of A Low-Energy Monoenergetic Electron Separator, Sergio Martín López Cáceres

LSU Master's Theses

The aim of this project is to build a prototype device that can select electrons of certain energy in order to have a monoenergetic beam suitable for the characterization of radiation detectors. Current options for sources of electrons are either from radioisotopes or accelerator facilities. Radioisotope sources are not tunable in energy since they depend on the nuclear and atomic structures of the daughter nucleus. On the other hand, even though accelerators offer the feature of a variable energy beam, they have limited availability and are not typically run at low intensities. Therefore, the motivation for this thesis is the …


Database Plan Quality Impact On Knowledge-Based Radiation Therapy Treatment Planning Of Prostate Cancer, Phillip Douglas Hardenbergh Wall Jan 2017

Database Plan Quality Impact On Knowledge-Based Radiation Therapy Treatment Planning Of Prostate Cancer, Phillip Douglas Hardenbergh Wall

LSU Master's Theses

Purpose: Knowledge-based planning (KBP) leverages plan data from a database of previously treated patients to inform the plan design of a new patient. This work investigated bladder and rectum dose-volume prediction improvements in a common KBP method using a Pareto plan database in VMAT planning for prostate cancer. Methods: We formed an anonymized retrospective patient database of 124 VMAT plans for prostate cancer treated at our institution. From these patient data, two plan databases were compiled. The clinical plan database (CPD) contained planning data from each patient’s clinical plan, which were manually optimized by various planners. The multi-criteria optimization database …


The Relationship Between The Timing Of Hydrocarbon Generation Between The Bristol Bay Depositional Basin And The Port Moller Area And Southern Portion Of The Bristol Bay Basin Of The Alaska Peninsula, Claire Rochelle Jones Jan 2017

The Relationship Between The Timing Of Hydrocarbon Generation Between The Bristol Bay Depositional Basin And The Port Moller Area And Southern Portion Of The Bristol Bay Basin Of The Alaska Peninsula, Claire Rochelle Jones

LSU Master's Theses

The Alaska Peninsula has been the target of oil and gas exploration throughout much of the 20th century. Although most exploration efforts have focused on the Cook Inlet area, the geological setting of the Alaskan Peninsula suggests that economically viable resources may be located further south on the northern side bordering Bristol Bay (Port Moller area). This study investigates the relation of petroleum system elements between the northern and southern section of the Alaskan Peninsula with a particular focus on the potential for petroleum accumulation on the southern section close to Herendeen Bay. The analysis included the integration of a …


Louisiana Birds Act As Reservoirs For Antibiotic-Resistant Bacteria, Collin T. Brown Jan 2017

Louisiana Birds Act As Reservoirs For Antibiotic-Resistant Bacteria, Collin T. Brown

LSU Master's Theses

Wild birds carry diverse microbial communities, including antibiotic-resistant bacteria (ARB). With the ever-increasing use of antibiotics in agricultural and clinical settings, genes that code for antibiotic resistance in bacteria have been selected for. These bacteria persist in the environment in a culturable state, but little is understood about communities of antibiotic-resistant bacteria in the environment. Birds with predictable behaviors may serve as useful indicators of these communities, and provide insights into how bacterial communities spread and evolve in the environment. To understand the utility of birds as indicators of the presence of antibiotic-resistant bacteria in the environment, we collected bacterial …


Analyzing User Comments On Youtube Coding Tutorial Videos, Elizabeth Heidi Poche Jan 2017

Analyzing User Comments On Youtube Coding Tutorial Videos, Elizabeth Heidi Poche

LSU Master's Theses

Video coding tutorials enable expert and novice programmers to visually observe real developers write, debug, and execute code. Previous research in this domain has focused on helping programmers find relevant content in coding tutorial videos as well as understanding the motivation and needs of content creators. In this thesis, we focus on the link connecting programmers creating coding videos with their audience. More specifically, we analyze user comments on YouTube coding tutorial videos. Our main objective is to help content creators to effectively understand the needs and concerns of their viewers, thus respond faster to these concerns and deliver higher-quality …


Modelling And Observational Evidence For The Igneous Evolution Of The Elysium Volcanic Province On Mars, David Andrew Susko Jan 2017

Modelling And Observational Evidence For The Igneous Evolution Of The Elysium Volcanic Province On Mars, David Andrew Susko

LSU Master's Theses

A major knowledge gap exists on how eruptive compositions of a single martian volcanic province change over time. The Elysium Volcanic Province is a location of great geologic interest on Mars. Its predominantly Amazonian surface age (beginning 3.3 Ga), and its isolation in the northern hemisphere of Mars away from other volcano-tectonic regions, make it an ideal locale to investigate igneous compositions erupted during the most recent geologic period on Mars. Here, this work seeks to fill that gap by assessing the compositional evolution of Elysium as a major martian volcanic province in two related projects. The first project seeks …


In Search Of Antarctica's Last Vegetation Refugium Within The Mcmurdo Dry Valleys, David Rau Jan 2017

In Search Of Antarctica's Last Vegetation Refugium Within The Mcmurdo Dry Valleys, David Rau

LSU Master's Theses

The McMurdo Dry Valleys, a hyper-arid cold polar desert located within the Transantarctic Mountains was once covered by vegetation. An in depth study of surface samples of various Neogene age, acquired throughout the Valleys, provide insight to the location of one of Antarctica’s last vegetation refugia. Boston University’s Antarctic Research Group has collected 82 surface samples from paleo lake sediments on 14 expeditions spanning 22 years in the McMurdo Dry Valleys. The ages of the samples are still not fully constrained, but 8 regions where samples were collected have been interpreted to range between 16.95 ± 0.17 to 4 Ma …


A Study On User Demographic Inference Via Ratings In Recommender Systems, Changbin Li Jan 2017

A Study On User Demographic Inference Via Ratings In Recommender Systems, Changbin Li

LSU Master's Theses

Everyday, millions of people interact with online services that adopt recommender systems, such as personalized movie, news and product recommendation services. Research has shown that the demographic attributes of users such as age and gender can further improve the performance of recommender systems and can be very useful for many other applications such as marketing and social studies. However, users do not always provide those details in their online profiles due to privacy concern. On the other hand, user interactions such as ratings in recommender systems may provide an alternative way to infer demographic information. Most existing approaches can infer …